CVIndependent

Mon06252018

Last updateWed, 27 Sep 2017 1pm

Robert Victor

At dusk in June, two planets clearly outshine all the stars. Venus, at magnitude -4 in the west-northwest, sets about 2.5 hours after sunset. Jupiter, near magnitude -2.4 in the southeast to south at dusk, reaches its highest point in the south about three hours after sunset on June 1, moving to one hour after sunset at month’s end.

Mercury passes superior conjunction on the far side of the sun on June 5. Near the perihelion of its orbit, it emerges very swiftly into the evening sky. Using binoculars, look very low in the west-northwest twilight glow, to the lower right of Venus, by 25 degrees on June 16; 20 degrees on June 25; and 17 degrees on June 30.

Later in the evening, Saturn rises within two hours after sunset on June 1, moving to around sunset on June 24, three days before opposition. Mars rises within four hours of sunset on the 1st, moving to about two hours after on the 30th. Find the Summer Triangle in the eastern sky at dusk as the season begins.

During June mornings:Jupiter on June 1 sets in the west-southwest nearly 1.3 hours before sunrise, and then 4 minutes earlier each morning. If your predawn walk occurs after Jupiter sets, you’ll see a sky dominated by Mars, in the south to south-southwest, while brightening nearly a magnitude, from -1.2 to -2.1. Saturn, near magnitude 0, is lower in the southwest, 28 to 34 degrees west of Mars. Prominent stars include the Summer Triangle, passing west of overhead; Fomalhaut in the southeast to south; Capella rising from the northeast; and Aldebaran emerging late in the month in the east-northeast.

This month features bright visible outer planets! On the morning of June 1, Spaceship Earth is heading toward constellation Aquarius, about 35 degrees to the east (left) of Mars. As our planet follows its nearly circular orbit around the sun, we overtake all three bright outer planets within 79 days, the shortest interval until 2078.

The asteroid Vesta> was the fourth to be discovered, in 1807. This month provides chances to see this asteroid with binoculars—and even the unaided eye in very dark skies. Begin with this finder chart which shows seven of the eight stars of the Teapot of Sagittarius. On the night of June 4, a line 5.7 degrees long, from 2.8-magnitude Lambda Sgr (Kaus Borealis, atop the Teapot’s lid) to 3.9-magnitude Polis (Mu Sgr), extended three degrees past Polis, ends near Vesta, magnitude 5.7. Vesta is retrograding in June, changing its place by about one-quarter of a degree daily for the rest of the month. Note the open cluster M23 within 2.5 degrees west of Vesta on June 4. On June 14, Vesta will pass closely southeast of M23. For a few days around its opposition on June 19, Vesta will reach magnitude 5.3, brighter than it will be again until July 2029.

For events at dawn, we suggest you begin viewing at least one hour before sunrise. For events at dusk, look one hour after sunset except when noted.

June 1 at dawn: The moon, nearly three days past full, is in the south-southwest at dawn, 5 degrees east (to the upper left) of Saturn and 23 degrees west (to the lower right) of Mars. Evening: Try to spot Saturn rising before Venus sets. Both are 4 degrees above opposite horizons about 2.2 hours after sunset. Three hours after sunset: The moon, just risen in the east-southeast, is 15 degrees to the lower left of Saturn.

June 2 at dawn: The waning gibbous moon is in the south to south-southwest, with Mars 12 degrees to the left, and Saturn 17 degrees to the lower right. Four hours after sunset: The moon, very low in the east-southeast, has Mars within 3 degrees to its lower right, and Saturn 27 degrees to its upper right.

June 3 at dawn: The moon is in the south, with Mars 2-3 degrees below. Saturn is 29 degrees to the lower right of the moon.

June 6-8 at dusk: A week after forming an isosceles triangle with the “Twin” stars Pollux and Castor, Venus now passes within 5 degrees to the lower left of Pollux. Look nightly, and see Venus move!

June 7-12, before dawn: The Martian south polar cap, where spring has recently begun, is now tipped 4-5 degrees toward the sun and a favorable 15 degrees into our view from Earth. The frozen carbon-dioxide polar cap is still near its maximum extent. Using your telescope with as high of a magnification as atmospheric conditions allow, look for a large bright area near the southern edge of Mars’ reddish disk. These mornings, the prominent dark marking Syrtis Major, the first Martian feature to be recorded in early telescopic observations, will appear near the center of the Martian disk on June 7 at 1:43 a.m., and about 38 minutes later each successive morning, until 4:54 a.m. on June 12. Around these times, Mars is well-placed in our sky for telescopic observation. Catch views of Syrtis Major up to two hours away from those times, provided Mars isn’t too low, or you don’t run into daylight.

June 11 at dawn: The moon is very low in the east-northeast to east. Use binoculars to spot the Pleiades cluster 15 degrees to the left of the rising moon.

June 12, 35 minutes before sunrise: Try to find the very old, thin crescent moon, 3 percent full, less than 3 degrees up, 17 degrees north of east.

June 13: The new moon, arriving at 12:43 p.m. is not visible today, neither at dawn nor at dusk.

June 14, 30 minutes after sunset: The crescent moon, some 32 hours old and 3 percent full, is 6 degrees up the in west-northwest. The moon sighting marks the end of Ramadan. Binoculars show Mercury 8 degrees to the moon’s lower right. Venus is easy to see with the unaided eye, 20 degrees to the moon’s upper left.

June 15, 30 minutes after sunset: The 8 percent crescent moon is 18 degrees up in the west to west-northwest, with Mercury 20 degrees to its lower right. Venus is within 7 degrees to the moon’s upper left.

June 16, beginning 30 minutes after sunset: The moon, at 16 percent, is well up in west, with Venus and Mercury 8 degrees and 33 degrees to the moon’s lower right. Mercury now sets a full hour after the sun.

June 17 at dusk: Regulus, heart of Leo, is within 4 degrees to the moon’s upper left. Mercury is 24 degrees to the lower right of Venus.

June 18 at dusk: Regulus is 11 degrees to the lower right of the moon.

June 19: The moon, nearing first-quarter phase, is almost 90 degrees east of the sun in the afternoon and evening sky, and appears almost half full. In the late afternoon, view or photograph the moon through a polarizing filter, rotating it to darken the blue sky, and you’ll improve the contrast well enough to observe lunar craters in the daytime! At dusk, Mercury forms an isosceles triangle with “Twin” stars Pollux and Castor 10 degrees above the planet. As twilight deepens, binoculars and telescope show the Beehive star cluster closely south of Venus.

June 20 at dusk: Can you see Saturn rising before Mercury sets? Both are nearly 5 degrees above opposite horizons at mid-twilight, 47 minutes after sunset. That makes four planets, Mercury-Venus-Jupiter-Saturn, visible simultaneously!

June 21 at 3:07 a.m.: The sun stands directly over the Tropic of Cancer, and summer begins for Earth’s Northern Hemisphere, with the shortest night and longest day. In Palm Springs, 12:48 p.m., the sun passes only 10.4 degrees south of overhead. Set up an Earth globe outdoors with your city at the top of the sphere, and the directions matched up, and your globe will have the same orientation as the Earth in space. Its axis will point nearly to the North Star, and the sunlit portion of the globe at any time of day you look will match reality. Note the North Pole is tipped into sunlight, and the South Pole is tipped into darkness.

June 21 and 22 at dusk: Spica in Virgo appears within 7 degrees to the lower left, and then 13 degrees to the lower right, of the waxing gibbous moon. On June 22, Jupiter appears within 10 degrees to the moon’s lower left.

June 23 at dusk: Jupiter is 5 degrees to the lower right of the moon. Mercury is 20 degrees to the lower right of Venus and closing.

June 24 at dusk: Mercury passes within 5 degrees to the south (lower left) of Pollux. Jupiter is 17 degrees to the moon’s upper right. On June 24 and 25 at dusk, Venus and Jupiter are about 90 degrees apart. Watch them draw together until late September, when they’ll be within 14 degrees.

June 25 at dusk: Antares, heart of Scorpius, is 8-9 degrees to the moon’s lower right.

June 26 and 27 at dusk: Mercury forms a nearly straight line with Pollux and Castor to its right. Saturn is 11 degrees to the moon’s lower left on June 26, and 1-2 degrees to the right of the full moon on June 27.

June 28 at dawn: The moon, just past full, is in the southwest, with Saturn, a day past opposition, 3-4 degrees to the moon’s lower right. At dusk, Saturn is within 13 degrees to the upper right of the moon.

June 30 at dawn: Mars is within 8 degrees to the left of the moon. On evening of June 30, Venus, Jupiter and Saturn span 135 degrees. Can you spot Mars before Venus sets? You’ll need a good vantage point; both are 2 degrees above opposite horizons about 2 1/4 hours after sunset.

The website of the Astronomical Society of the Desert at www.astrorx.org has a listing of our evening star parties. Sawmill Trailhead, our high-altitude site (elevation 4,000 feet), will have a star party starting at dusk on Saturday, June 9.

Abrams Planetarium publishes a monthly Sky Calendar with an evening sky map. Subscriptions are $12 per year. Subscribe or view a sample issue at www.abramsplanetarium.org/skycalendar.

Wishing you clear skies!

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. He is now retired and enjoys providing sky watching opportunities for a variety of groups in the Coachella Valley. Robert D. Miller did graduate work in planetarium science and later astronomy and computer science at Michigan State University and remains active in research and public outreach in astronomy.

Two planets far outshine all the stars this month. May through June, Venus, at magnitude -4 in the west-northwest at dusk, attains peak altitude of its current apparition and sets a maximum of 2.6 hours after sunset.

Jupiter—magnitude -2.5, its brightest of the year—passes opposition to the sun and all-night visibility on May 8. Watch it climb from very low in the east-southeast at dusk on May 1 to 30 degrees up in the southeast by month’s end.

Next in brilliance at dusk in May are blue-white Sirius (magnitude -1.4) until its departure in the west-southwest, and three zero-magnitude stars: golden-orange Arcturus, high in the east to east-southeast; blue-white Vega, rising into view in the northeast; and yellow Capella, sinking in northwest.

In the morning: Jupiter, in the west-southwest at dawn, is easily the brightest morning “star” until it drops out late in the month. It sets 4-5 minutes earlier each morning, so you can still catch it at month’s end simply by looking before dawn starts to brighten. Next is Mars, hovering in the south while doubling in brightness from magnitude -0.4 to -1.2. Ranking after Mars are Arcturus, sinking in the west to west-northwest; Vega, just northwest of overhead; and Saturn, 15 to 28 degrees west of Mars. Other stars visible include Altair and Deneb, completing the nearly overhead Summer Triangle with Vega; Antares, low in the southwest, below the line joining Jupiter and Saturn; and Fomalhaut, low in the southeast. Mercury, brightening slowly from magnitude +0.4 to -0.6 May 1-21, is very low in the east to east-northeast in dawn twilight. In this poor apparition, binoculars are recommended.

May through July 2018 is a special time for planets! On the morning of May 1, Spaceship Earth is heading toward a direction in space about 17 degrees east (left) of Mars. As our planet follows its nearly circular orbit around the sun, we will overtake all three bright outer planets within 79 days, the shortest interval since 1984, and shortest until 2078. Each body will take its turn at opposition and all-night visibility, starting with Jupiter on May 8.

For events at dawn, we suggest viewing at least one hour before sunrise. For events at dusk, look one hour after sunset.

Tuesday, May 1, at dawn: The moon is in the southwest, just past full, with Jupiter 9 degrees to its lower right. Mars-Saturn are 15 degrees apart in the south. Mercury is rising just north of east. Dusk: Venus and Jupiter are 160 degrees apart.

May 2, at dawn: Antares is 8 degrees to the lower left of the moon. Jupiter 21 is degrees to the moon’s lower right. Dusk: Aldebaran, eye of Taurus, is 6 degrees to the lower left of Venus. Binoculars show the Hyades star cluster in same field as Aldebaran. Together, they form the head of the Bull.

Before this month is over, we’ll lose our views of four of winter’s bright stars as they sink into the western twilight glow. In order of disappearance, they are Rigel, Aldebaran, Sirius and Betelgeuse.

May 3 at dawn: Saturn is 16 degrees, and Mars 32 degrees, to the east (left) of the moon. Through a telescope, the phase of Mars matches the moon’s this morning, 88 percent. The dark marking on Mars known as Syrtis Major appears closest to the center of the Martian disk at 3:43 a.m., and 39 minutes later each successive morning.

May 4 at dawn: Saturn is 4 degrees to the left of the moon. A telescope shows Saturn’s rings tipped nearly 26 degrees from edgewise.

May 5 at dawn: Mars is 9 degrees to the lower left of the waning gibbous moon. Four planets, from Jupiter low in southwest to west-southwest, to Mercury rising just north of east, span 150 degrees.

Sunday, May 6, at dawn: Mars is 3 degrees to the lower right of the moon. Can you detect the bright South Polar Cap, or its cloud cover? Later this month, spring will begin in the Martian southern hemisphere, and the frozen-carbon-dioxide polar cap is near its maximum extent.

May 7 at dawn: The moon, just over half full, is approaching last-quarter phase. Note Mars 14 degrees to the moon’s right.

May 8 at dawn: The moon, in the southeast, is less than 90 degrees west of the sun, so it has passed last-quarter phase and appears as a fat crescent. Find Mars 26 degrees west of the moon. All night: Jupiter is at opposition and visible from dusk until dawn as Earth passes between that planet and the sun.

May 9 at dusk: Venus and Jupiter are within 150 degrees and closing.

May 12 at dawn: The last-day crescent moon is above the horizon one hour before sunrise, just north of east, 5 degrees up, 11 percent full. Dusk: Venus passes 4 degrees south (to the lower left) of second-magnitude Elnath (Beta Tauri, Bull’s northern horn) tonight and tomorrow.

Sunday, May 13: Look about 40 minutes before sunrise to catch the 5-percent crescent old moon just risen 5 degrees north of east. Binoculars may show Mercury 4 degrees to the left of the moon and slightly higher.

May 13-21 at dusk: Look for the red-supergiant star Betelgeuse, shoulder of Orion, 18 degrees to the lower left of Venus. If you look daily at same stage of twilight, Betelgeuse will appear about 1 degrees lower each evening. On what date will you last spot it?

May 16 at dusk: The first crescent moon, 4 percent full, is low in the west-northwest, 11 degrees below Venus.

May 17 at dusk: The crescent moon, 10 percent full, is within 7 degrees to the left of Venus and slightly higher. Telescopes show Venus 84 percent full. Can you still see Betelgeuse? Look 13 degrees to the moon’s lower left.

May 18 at dusk: “Twin” stars Pollux and Castor are 4.5 degrees apart, 10-13 degrees to the upper right of the moon. Venus is 18 degrees to the moon’s lower right. Procyon is 16 degrees to the moon’s left and a little lower.

May 19 at dusk: The twins are 11-16 degrees right of the moon. Procyon is 16 degrees to the moon’s lower left. After dark: Binoculars show the Beehive star cluster within 6 degrees to the moon’s upper left.

Sunday, May 20 at dusk: Venus and Jupiter are 135 degrees apart and closing.

May 21 at dusk: The first-quarter moon is half full. Regulus, heart of Leo, is a degree to the moon’s lower right. As we look toward the moon and Regulus tonight, we are looking out the “rear window” of Spaceship Earth, opposite to the direction we are moving around the sun. Later this evening, Venus has its northernmost setting of this year.

May 23: It’s the first day Saturn rises before Venus sets, but only by 5 minutes. With mountains surrounding us, it is difficult to find a spot to see both planets simultaneously—but the “window” of opportunity opens 5 minutes wider each day.

May 25 at dusk: Spica in Virgo is within 7 degrees to the lower right of the waxing gibbous moon.

May 26 at dusk: Jupiter is within 9 degrees to the moon’s lower left.

Sunday, May 27, at dusk: The moon is in the southeast, with Jupiter 6 degrees to its lower right.

May 28: The nearly full moon rises some 43 minutes before sunset. Can you catch the sun and moon simultaneously? At dusk, note Jupiter 18 degrees to the moon’s upper right, and Antares 11 degrees to the moon’s lower right.

May 29: The moon, just past full, rises about 13 minutes after sunset. At dusk, Jupiter is 30 degrees to the upper right of the moon. Antares, heart of Scorpion, is 10 degrees to right of the moon.

May 30 at dusk: Venus is 10 or 11 degrees below the “Twins” tonight and tomorrow, forming a nearly isosceles triangle.

May 31 at dusk: Venus and Jupiter appear 120 degrees apart tonight. As we approach the dates of the oppositions of Saturn and Mars in late June and late July, respectively, those planets are beginning to appear in late evening: Saturn now rises within two hours after sunset, and Mars rises just two hours after Saturn.

The website of the Astronomical Society of the Desert at www.astrorx.org has a listing of our evening star parties at two locations. The primary, more accessible location is at the Visitor Center of the Santa Rosa and San Jacinto Mountains National Monument (on Highway 74, within 4 miles south of Highway 111 in Palm Desert). Our last sky viewing session for the season at that location is scheduled on Saturday, May 19, from 8 to 10 p.m.Sawmill Trailhead, our high-altitude site (elevation 4,000 feet), will have a star party starting at dusk on Saturday, May 12. (Star parties at that location will continue monthly.) Listings on the society’s website includes maps and directions for both locations. Star parties can be cancelled in poor observing weather. Also, check the link to “Impromptu Star Parties” on that website for star parties announced on short notice. There will be some in Palm Springs during May.

The Abrams Planetarium is making available online the May 2018 Sky Calendar with an evening sky map. It may be reprinted for free distribution. To download the calendar and map, visit www.abramsplanetarium.org/skycalendar.

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. He is now retired and enjoys providing sky-watching opportunities for a variety of groups in the Coachella Valley. Robert D. Miller did graduate work in planetarium science and later astronomy and computer science at Michigan State University and remains active in research and public outreach in astronomy.

The two brightest “stars” in the April evenings are really planets. Venus continues to gain altitude in the west to west-northwest at dusk, as the time of its setting shifts from 1.6 hours after sunset on April 1, to 2.2 hours after on the 30th. Jupiter doesn’t appear on our evening mid-twilight chart until almost month’s end; it rises in east-southeast just more than three hours after sunset on the 1st, to just more than a half-hour after on the 30th.

Next in brilliance at dusk are blue-white Sirius in the southwest; golden orange Arcturus climbing in the east-northeast to east; and yellow Capella, high in the northwest.

In the morning, Jupiter, in the southwest at dawn, is easily the brightest morning “star.” Ranking next are Arcturus in west, and Vega passing just a few degrees north of overhead. Mars, just east of due south, is slightly fainter than these stars as April begins. But as Earth closes its distance to Mars—from 103 million miles on the 1st to 79 million miles on the 30th—the planet begins to outshine those stars. In early April, Mars is closely accompanied by Saturn; they appear closest, within 1.3 degrees, on April 2. By month’s end, Mars-Saturn are 14 degrees apart.

Other bright stars in the morning sky are Altair and Deneb, completing the Summer Triangle with Vega; Antares, between Jupiter and Saturn, but below the line joining these two giant planets; and Spica, sinking in the west-southwest, to the lower right of Jupiter and lower left of Arcturus. On April 13, Spica is at opposition as the Earth passes between that star and the sun. On April 13-14, look for Spica in the east-southeast at dusk, well up in south in middle of night, and low in the west-southwest at dawn. Mercury, brightening slowly from magnitude +1.0 to +0.4 during April 19-30, is very low in the east in dawn twilight. In this poor apparition, binoculars are recommended.

On the morning of April 2, Spaceship Earth is heading toward a direction in space within 4 degrees east (to the left) of the Mars-Saturn pair. As our planet follows its nearly circular orbit around the sun, we will overtake all three bright outer planets, and each will take its turn at opposition and all-night visibility: Jupiter on May 8, (Antares on May 31), Saturn on June 27, and Mars on July 26. Mars, the next planet outward from Earth, will brighten spectacularly in July, outshining even Jupiter.

For events at dawn, the suggested viewing time is generally one hour before sunrise. For events at dusk, look one hour after sunset, except when noted.

Easter Sunday, April 1, at dawn: Spica is 6 degrees south of the moon in the west-southwest. Jupiter is in the south-southwest to southwest, 29 degrees to the upper left of the moon. The Mars-Saturn pair is in the south-southeast, 1.4 degrees apart, about 46 degrees left of Jupiter.

April 2 at dawn: Mars passes within 1.3 degrees south of (below) Saturn; the pair is 47 degrees east (left) of Jupiter. Red supergiant star Antares, heart of the Scorpion, is 19 degrees to the lower left of Jupiter and 29 degrees to the lower right of Mars.

April 3 at dawn: Mars-Saturn are 1.4 degrees apart. Jupiter is within 4 degrees to the lower left of the moon in the southwest. Four hours after sunset: The moon is low in the east-southeast, within 9 degrees to the lower left of Jupiter.

April 4 at dawn: Jupiter is 11 degrees to the lower right of the moon; Antares is 11 degrees to the lower left of the moon.

April 5 at dawn: Antares is within 10 degrees to the lower right of the moon. Mars-Saturn are 2 degrees apart.

April 6 at dawn: Mars-Saturn are 2.4 degrees apart, 12-14 degrees east (to the left) of the moon. Four solar system bodies—in order from west to east, Jupiter, the moon, Saturn and Mars—span 49 degrees.

April 7 at dawn: A beautiful gathering of the moon and two planets fits within the field of view of binoculars: Saturn about 1 degree to the moon’s lower right, with Mars just more than 3 degrees to the moon’s lower left.

Sunday, April 8 at dawn: The moon, in the south-southeast, has just passed last quarter phase and appears slightly less than half-full. All three bright morning planets are now west of the moon—Mars and Saturn by 9 and 12 degrees, respectively, and Jupiter by 59 degrees.

April 9 at dawn: Mars-Saturn are 4 degrees apart, 20 to 24 degrees to the upper right of the fat crescent moon.

April 11 at dawn: Mars-Saturn are 5 degrees apart.

April 12 at dawn: The distance from the crescent moon, low in the east-southeast, to Jupiter, in the southwest, spans 108 degrees. Dusk: Venus appears 15 degrees directly below the Pleiades star cluster, aka the Seven Sisters.

April 13 at dawn: This the last easy chance to view the waning crescent moon, rising within 10 degrees south of east in twilight; Spica is at opposition in the west-southwest. Between them, find Jupiter in the southwest, and Saturn and Mars 6 degrees apart in the south to south-southeast. At dusk: Find Spica low in the east-southeast. When Spica passes due south in the middle of night, look 36 degrees below it and only 3-4 degrees up for the globular cluster Omega Centauri, some 17,000 light-years away. Seen through binoculars in very dark skies, it appears as a round, fourth-magnitude fuzzy ball about as large as the moon.

Sunday, April 15: The new moon, closely south of the sun at 6:57 p.m., is invisible today!

April 16, about 25-40 minutes after sunset: From a place with an unobstructed view, some 10 degrees north of west, try to see the thin crescent moon, very low—2 to 5 degrees above the horizon—within 13 degrees below and slightly left of Venus. The moon’s age is about 25 hours past new. As the sky darkens, look for the Pleiades cluster 10 degrees above Venus. Binoculars give best views of the moon and of Pleiades.

From places with unobstructed views toward the east-southeast and west-northwest, Jupiter now rises just 8 minutes before Venus sets, and it is briefly possible to observe both planets simultaneously above opposite horizons. By April 24, Jupiter will rise one hour before Venus sets, so it will become easier to do so. By April 30, Jupiter will rise 99 minutes before Venus sets. It remains possible to observe these two bright planets simultaneously at dusk until early October, when Venus sinks into twilight.

April 17 at dawn: Mars and Saturn are 8 degrees apart. At dusk: Venus appears within 6 degrees to the right of the crescent moon, with earthshine illuminating the moon’s dark side.

April 18 at dusk: Don’t miss this special, beautiful sight! Within an hour after sunset, the moon is framed by the V-shaped head of Taurus, the Bull, composed of bright Aldebaran (marking the Bull’s eye 67 light years away, within 2 degrees to the moon’s upper left), and the fainter remaining stars of the “V,” members of the more distant Hyades cluster. Watch the moon close in on Aldebaran as the evening progresses. By 10 p.m., the star appears just 1 degree to the upper left of the moon’s center.

April 19 at dusk: Pleiades is 7 degrees to the upper right of Venus, with Aldebaran 13 degrees to the lower right of the moon.

April 20 at dusk: Betelgeuse, shoulder of Orion, is 15 degrees to the lower left of the moon. Below Betelgeuse, look for Orion’s three-star belt, and still lower, Orion’s foot, Rigel. Look for these stars each evening within an hour after sunset in coming weeks, and watch for their annual departures below the western horizon.

April 21 at dawn: Mars and Saturn are 10 degrees apart. Dusk: Pleiades is 5 degrees to the upper right of Venus. Pollux is 9 degrees to the upper right of the moon, with Procyon 15 degrees to the moon’s lower left.

Sunday, April 22, predawn darkness hours: It’s the peak of the Lyrid meteor shower. In early afternoon, the moon passes first quarter, 90 degrees east of the sun, and appears half full. In the late evening, the moon passes 2 degrees south of the Beehive cluster. You’ll need binoculars or a telescope to see the cluster’s stars so close to the moon.

April 23 at dusk: Regulus is 10 degrees to the lower left of the moon. Venus is within 4 degrees south (lower left) of Pleiades.

April 24 at dawn: Three bright outer planets—from west to east, Jupiter, Saturn and Mars—span 60 degrees. Mercury is also visible, very low in the east. Dusk: Regulus, heart of Leo, the Lion, is 4 degrees to the moon’s upper right. Venus’ least distance from Pleiades occurs tonight, as the planet passes 3.5 degrees south of the cluster’s brightest member.

April 25 at dusk: Pleiades is 4 degrees to the right of Venus, with Aldebaran 10 degrees to Venus’ upper left.

April 26 at dusk: Venus is nearly on line, joining Pleiades and Aldebaran.

April 27 at dusk: Spica is 11 degrees to the lower right of the moon.

April 28 at dusk: Spica is 8 degrees to the right of moon and a little higher. Watch for Jupiter rising 21 degrees to the lower left of the moon.

Sunday, April 29 at dusk: Venus is equidistant from Pleiades and Aldebaran—7 degrees from each. The full moon is 19 degrees to the lower left of Spica and 8 degrees above Jupiter.

April 30 at dawn: Jupiter is 5 degrees to the left of the moon in the southwest to west-southwest. Mars-Saturn are 14 degrees apart in the south-southeast to south. At dusk, watch for moonrise 6 degrees to the lower left of Jupiter in the east-southeast.

The website of the Astronomical Society of the Desert  has a listing of our evening star parties at two locations. The primary, more accessible location is at the visitor center of the Santa Rosa and San Jacinto Mountains National Monument (on Highway 74, within four miles south of Highway 111 in Palm Desert). A sky viewing session is scheduled there on Saturday, April 21, from 8 to 10 p.m. Sawmill Trailhead, our high-altitude site (elevation 4,000 feet), will have a star party starting at dusk on Saturday, April 14. Listings of star parties on the website include maps and directions for both locations. Star parties can be cancelled in poor observing weather. Also, check link to “Impromptu Star Parties” on that website for star parties announced on short notice.

Robert Victor was a staff astronomer at Abrams Planetarium at Michigan State University. He is now retired and enjoys providing sky watching opportunities for a variety of groups in the Coachella Valley. Robert D. Miller did graduate work in planetarium science and later astronomy and computer science at Michigan State University and remains active in research and public outreach in astronomy.

As was the case back in January, March 2018 has two full moons. The first one almost coincides with its rising at sunset on the March 1. The second full moon of the month, sometimes called a “Blue Moon,” occurs in morning twilight on the 31st, before its setting just after sunrise. The moon will not be unusually close this time, nor will there be an eclipse, so there won’t be much media hype about this year’s second “Blue Moon” on March 31.

In March 2018, the predawn sky continues to host the three bright outer planets, all fitting within a span of 44 to 46 degrees. Starting with the full moon on March 1, follow the waning moon each morning through the 15th, and watch it pass above bright Jupiter on March 7, then skip from right to left of Mars March 9 and 10, and from right to left of Saturn March 10 and 11.

In the early evening, Venus can be spotted as a bright point of light very low in the western twilight glow, its visibility improving as the time of its setting after the sun broadens from 57 minutes to 93 minutes. Mercury can be spotted in the same binocular field as Venus for first three weeks, but fades rapidly after mid-month. Catch the moon at dusk on March 18 as a thin crescent low in the west, to the lower left of Venus and Mercury. Then follow moon nightly until March 31, when it’s full, rising just south of east within a half-hour after sunset. After Venus, evening’s most prominent point of light is Sirius, the “Dog Star,” the in southern sky at dusk in March.

Our morning chart for March depicts daily positions of all three bright outer planets and the half-dozen stars of first magnitude or brighter visible all month about 40 minutes before sunrise, before they fade into twilight. Jupiter, of magnitude -2.2 to -2.4 in the south-southwest to southwest, is the brightest “star” at dawn. The brightest actual stars are golden Arcturus, high in the southwest to west, and blue-white Vega, very high in the east-northeast to northeast. Saturn, of magnitude +0.6 to +0.5 in the south-southeast, glows about 45 degrees east of Jupiter. Mars, brightening from magnitude +0.8 to +0.3 and starting to outshine Saturn, strangely seems to hover nearly stationary in the sky all month, just more than 30 degrees up in the south-southeast to south. But Mars is really shifting nearly 0.6 degrees per day east against the background of stars, which appear to be sliding westward behind the planet. Watch Mars narrow its distance west of Saturn from 15 degrees on March 4, to 10 degrees on March 14, 5 degrees on March 24, and 2 degrees on March 30. Against stars on March 29, Mars passes within 1.9 degrees north of (above) third-magnitude Lambda, or Kaus Borealis, the northern star of the bow of Sagittarius, the Archer.

Look about an hour before sunrise to catch these events:

March 1: Regulus is 4 degrees to the lower right of the full moon.

March 4 and 5: Spica is 10 degrees to the lower left, then 8 degrees to the lower right, of the waning gibbous moon.

March 7: Jupiter is 4 degrees to the lower right of the moon, now two-thirds full.

March 8: Antares, heart of Scorpius, is 9 degrees below the moon.

March 9: Mars is 6 degrees to the lower left of the last quarter (half full) moon. Also, Jupiter, two months before its opposition, is stationary against background stars 8 degrees east of third-magnitude Alpha in Libra, and begins to retrograde.

March 10: Mars is 7 degrees to the right of the fat crescent moon. Saturn is 6 degrees to the lower left of the moon.

March 11: Saturn is 6 degrees to the right of the moon.

March 15: This is the last chance for the thin old crescent moon, very low in the east-southeast in twilight.

March 31: Spica is 15 degrees to the upper left of the moon.

In the evening: Have you ever seen Mercury? Here’s your chance! Our solar system’s innermost (and smallest known) planet has its best evening appearance of this year in the first three weeks of March. It sets in a deeper stage of twilight than it will during either of its two other evening showings, in July and November. And in March, Mercury will be very easy to find, within the same binocular field as Venus. All you need is a clear sky very low in the west, and an unobstructed view, without nearby high mountains blocking your line of sight toward the planet duo. Choose your viewing site carefully!

On March 1, Mercury will shine at magnitude -1.3, only 1.7 degrees to the lower right of 10-times-brighter Venus, at magnitude -3.9. On March 2, they’re 1.3 degrees apart, and on March 3, Mercury passes within 1.1 degrees to the right of Venus, with the pair setting just within an hour after sunset. Night by night, Mercury creeps a little farther to the upper right of Venus, to 2 degrees by March 6, on to a maximum of 4.1 degrees of Venus on March 14.

On March 15, Mercury, still bright at magnitude -0.3, reaches greatest elongation, 18 degrees from the sun, and at the end of its apparent orbit as we observe it from Earth. Mercury is then rapidly approaching Earth and begins to curve around to the near side of its orbit, where telescopically, it presents an ever-thinner crescent, fading as the planet’s surface features, large and small, cast shadows. Faded to magnitude +0.3, Mercury reaches a secondary minimum distance of 3.8 degrees to the upper right of Venus on March 18, the same evening when the 37-hour-old crescent moon passes 4 degrees to the south (lower left) of brilliant Venus.

On March 20, spring begins at 9:15 a.m., as the sun passes directly over the equator. That evening, the two inner planets set together, Mercury faded to magnitude +0.9, appearing 4.1 degrees to the right of Venus. Thereafter, Mercury quickly drops into bright twilight and fades. On March 21, it has faded to magnitude +1.2 and appears 4.5 degrees to the lower right of Venus. On the 22nd, Mercury is 5.2 degrees to the lower right of Venus, and is a challenging magnitude +1.5.

Orion’s three-star belt, not shown because its stars are of just second magnitude, is prominent in the south to southwest at dusk. It is flanked by red Betelgeuse, his shoulder, and blue-white Rigel, his foot. Extend the belt eastward to Sirius, the brightest star. Extend the belt in the opposite direction, and bend north a bit to Aldebaran, eye of Taurus. Some 14 degrees farther, locate a compact cluster of stars, the Pleiades, or Seven Sisters, a beautiful sight for binoculars! Procyon, the lesser Dog Star, completes the Winter Triangle with Betelgeuse and Sirius. North of the Winter Triangle, Orion and Taurus lie Pollux and Castor, the twin stars of Gemini, just 4.5 degrees apart, and Capella, the Mother Goat Star. Regulus, heart of Leo, follows the whole shebang across the sky, as if chasing his dinner menu items.

The moon is near bright objects in evening sky:

March 1: Regulus is 13 degrees to the upper right of the full moon.

March 18: Venus and Mercury are 4.1 and 7.6 degrees, respectively, to the upper right of a young crescent moon low in the west.

March 22: Aldebaran is 2 degrees below the moon.

March 25: Pollux is 9 degrees north of the moon; Procyon is 14 degrees south of the moon.

March 27 and 28: Regulus is 6 degrees to the lower left, then 8 degrees to the upper right, of the moon.

March 31: Before the end of twilight, watch for the rising of Spica, within 8 degrees to the lower right of the moon, just past full.

On Friday, March 2, Dennis Mammana, author of six books on astronomy and the “Stargazer” nationally syndicated newspaper column, will present a lecture at the Portola Community Center, 45480 Portola Ave., in Palm Desert. Doors open at 6:30 p.m. for refreshments, and the talk begins at 7 p.m.

The website of the Astronomical Society of the Desert has a listing of our lectures, and of our evening star parties at two locations. The primary location is at the Visitor Center of the Santa Rosa and San Jacinto Mountains National Monument (on Highway 74, within 4 miles south of Highway 111, in Palm Desert). A sky viewing session is scheduled there on Saturday, March 10, from 6 to 9 p.m. Sawmill Trailhead, our high-altitude site (elevation 4,000 feet), will have a star party starting at dusk on Saturday, March 17. Star parties can be cancelled in poor observing weather. See also the link to “Impromptu Star Parties” on the website.

Also, check out the Sky’s the Limit Observatory and Nature Center in Twentynine Palms, at skysthelimit29.org.

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. He is now retired and enjoys providing sky watching opportunities for a variety of groups in the Coachella Valley. Robert D. Miller did graduate work in Planetarium Science and later astronomy and computer science at Michigan State University and remains active in research and public outreach in astronomy.

In February 2018, the predawn sky hosts all three bright outer planets, spanning 44 degrees. After the total lunar eclipse at dawn on Jan. 31, follow the waning moon each morning in the first half of February, and watch it pass Jupiter on Feb. 7; Mars on Feb. 9; and Saturn on Feb. 11.

Evenings offer the challenge of spotting Venus low in the western twilight glow, getting easier as its setting time improves from 24 to 56 minutes after sunset. Follow the waxing moon evenings from Feb 16, as a thin crescent near Venus, until March 1, when it’s full. Until Venus emerges from bright twilight, the evening’s most prominent point of light is Sirius, the brilliant “Dog Star,” in the southeast at dusk in February.

Our morning twilight chart for February shows bright Jupiter nearly 40 degrees up in the southern sky. On Feb. 1, Mars is 12 degrees to Jupiter’s lower left, with Saturn another 31 degrees to the lower left of Mars. On Feb. 1, note the moon, two bright stars and the three planets lie in a long straight line across the sky, from the moon in west, to Saturn in southeast. In order that morning, they are: the moon, Regulus, Spica, Jupiter, Mars and Saturn. Note also the reddish star Antares, heart of the Scorpion, to the lower left of Mars on Feb. 1. Look about an hour before sunrise each morning through Feb. 13, and watch for these events:

Feb. 2: Regulus is 11 degrees to the lower right of the moon.

Feb. 5: Spica is 6 to 7 degrees to the lower left of the moon.

Feb. 7: Jupiter is 5 degrees to the lower left of the last-quarter moon—half full and 90 degrees, or a quarter-circle, west of the sun. Mars appears within 6 degrees of Antares for 10 mornings, Feb. 7-16. Compare them in color and brightness. At closest approach in late July 2018, Mars will outshine Jupiter!

Feb. 8: Jupiter is within 9 degrees to the right of the fat crescent moon. Mars is within 9 degrees to the moon’s lower left, while Antares is 5.5 degrees below Mars.

Feb. 9: Mars is 5 degrees to the lower right of the moon, with Antares 9 degrees to the lower right of the moon, and 5.3 degrees to the lower right of Mars. Saturn is within 24 degrees to the lower left of the moon. Jupiter is 20 degrees to the moon’s upper right.

Feb. 10: Visualize our dynamic solar system as you observe the planets in the morning sky. Today, Jupiter lies directly ahead of Spaceship Earth in our orbital motion around the sun. We’ll curve around the sun to pass between Jupiter and the sun in early May, and that planet will appear at opposition, 180 degrees from the sun. We’ll similarly overtake Saturn in late June, and Mars in late July, each taking its own turn at opposition.

Feb. 11: Saturn is within 2 degrees to the lower right of a striking lunar crescent, with earthshine illuminating the moon’s dark (non-sunlit) side. Mars and Antares, now 26 to 27 degrees to the moon’s upper right, appear closest together, just 5.1 degrees apart this morning and tomorrow. Mars, moving 0.6 degrees east daily against background stars, will appear midway between Jupiter and Saturn, 22 degrees from each, on Feb. 19.

Feb. 12: The waning crescent moon, only 10 percent full, is low in the east-southeast to southeast, 12 degrees to the lower left of Saturn.

Feb. 13: The last easy-to-see crescent moon, 5 percent full, is 24 degrees to the lower left of Saturn. The Mars-Antares pair is 5.2 degrees apart, within 19 degrees to the lower left of Jupiter.

Feb. 14: You have one last chance to catch the waning moon: Just 25 minutes before sunrise, if the sky is very clear, look 2 degrees up in the east-southeast for the hairline old crescent, 2 percent full and 31 hours before the invisible new moon, which occurs on Feb. 15 at 1:05 p.m.

February’s evening twilight sky chart plots Venus barely above the horizon 40 minutes after sunset, just south of west, in the last 10 days of month. Improve your chances to spot Venus and begin seeing it earlier in month by using binoculars and looking closer to the time of sunset. Find a spot where mountains won’t block your view! The brightest stars are Sirius in the southeast, and Capella, very high, northeast to north of overhead. They mark the southern and northern vertices of the huge Winter Hexagon, in clockwise order from Capella: Aldebaran, Rigel, Sirius, Procyon, the Twins (Pollux and Castor) and back to Capella. Orion’s shoulder, Betelgeuse, sits inside. Regulus, heart of Leo in the east, chases the Winter Hex across the sky.

Here are some of this month’s evening events:

Feb 16: Around 5:22 p.m., or 22 minutes after sunset, the sun is 5 degrees below the horizon, while the young crescent moon, only 1 percent illuminated, is 6 to 7 degrees up and 16 degrees south of due west. Very clear skies and an unobstructed horizon are essential for success within the next 10-minute window, and binoculars will greatly increase your chances. Venus appears as a point of light within 3.4 degrees to the lower right of the illuminated lower right limb of the moon. You’re likely to spot Venus first, since its light is concentrated within a tiny disk. If so, look to the upper left of Venus for the faint arc of the nearly 29-hour-old crescent.

Feb. 17: About 25 minutes after sunset, the sun is 6 degrees below the horizon (civil twilight), while the moon is 17 degrees up, 9 degrees south of due west. At 5 percent, the crescent should be easy to see in clear skies. Can you spot Venus 15 degrees to the moon’s lower right and just 3 degrees up? Venus is just beginning its evening apparition, lasting until early October.

Feb. 18: Regulus is at opposition as Earth passes between that star and the sun. Tonight, Regulus is visible all night.

Feb. 22: The moon, nearing first-quarter phase when it’s 90 degrees east of the sun and appearing half-full, is 9 degrees south of the Pleiades (Seven Sisters) star cluster this evening, and 9 degrees west of Aldebaran, eye of Taurus. By moonset tonight, the moon will appear 6 degrees to the lower right of Aldebaran.

Feb. 23: At dusk, the slightly gibbous moon is high in the south, with Aldebaran 5 degrees to its lower right. Note Betelgeuse 17 degrees to the moon’s lower left.

Feb. 24: The moon and Betelgeuse, 12 degrees to its lower right, lie near the center of the Winter Hexagon.

Feb. 25:Between tonight and tomorrow, the moon moves from inside to outside the Hexagon, jumping over the line joining Pollux, the brighter and more southerly Gemini Twin, and Procyon, the Little Dog Star.

Feb. 26: The moon is 10 degrees southeast of Pollux, in line with Pollux and its fainter Twin Castor.The Twins are 4.5 degrees apart, with Castor northwest of Pollux and farther from the moon.

Feb. 27: Find Regulus, the heart of Leo, 16 degrees to the moon’s lower left.

Feb. 28: As evening twilight deepens, use binoculars to spot Regulus only about 1 degree to the moon’s lower right. Check every half hour; shortly after 9 p.m., the moon will pass closely north of the star, with less than a moon’s width of clearance between them. From the Arctic, the moon will occult or cover the star. At dawn on March 1, the moon will have moved 4 degrees east (to the upper left) of the star.

On Friday, Feb. 2, Bruce M. Gottlieb, president of the Astronomical Society of the Desert, will be speaking on “The Total Solar Eclipse of August 21, 2017.” Gottlieb will explain why eclipses happen, and share photos from his trip to Casper, Wyo., to view the eclipse. On Friday, March 2, Dennis Mammana, author of six books on astronomy and the “Stargazer” syndicated newspaper column, will present a lecture on an astronomy topic to be determined. Both lectures will be held at the Portola Community Center, 45480 Portola Ave., in Palm Desert. Doors open at 6:30 p.m., and the talks begin at 7 p.m.

The website of the Astronomical Society of the Desert has a listing of our lectures and of our evening star parties at two locations. The primary, more-accessible location is at the Visitor Center of the Santa Rosa and San Jacinto Mountains National Monument (on Highway 74, within four miles south of Highway 111 in Palm Desert). A sky viewing session is scheduled there on Saturday, Feb. 10, from 6 to 9 p.m. Sawmill Trailhead, our high-altitude site (elevation 4,000 feet), will have a star party starting at dusk on Saturday, Feb. 17. Star parties can be cancelled in poor observing weather. Also find the link to “Impromptu Star Parties” on the website.

Finally, check out the Sky’s the Limit Observatory and Nature Center in Twentynine Palms, at skysthelimit29.org.

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. He is now retired and enjoys providing sky watching opportunities for a variety of groups in the Coachella Valley. Robert D. Miller did graduate work in planetarium science and later astronomy and computer science at Michigan State University and remains active in research and public outreach in astronomy.

In January 2018, mornings are when most of the action takes place. The predawn sky hosts as many as four planets, including close pairings—Mars-Jupiter on Jan. 4-9, and Mercury-Saturn on Jan. 11-14.

Also: January has two full moons! Follow the waning moon mornings in first half of month, and watch it pass the four planets—Mars-Jupiter on Jan. 11, and Mercury-Saturn on Jan. 14 and 15.

Finally, don’t miss the total lunar eclipse on Jan. 31!

Evenings offer no naked-eye planets, but they do offer a waxing moon Jan. 17-30, and an uncommonly large number of bright stars with the appearance of Sirius, the brilliant “Dog Star” in the east-southeast.

Our New Year starts out with a “Supermoon,” the closest of 2018. As seen from Palm Springs, the full moon on Jan. 1 rises as the sun sets, at 4:49 p.m. A few minutes later, look for the huge disk of the moon resting on the horizon in the east-northeast. The moon will be up all night, setting at 7:17 a.m. on Jan. 2, some 26 minutes after sunrise.

Despite the full moon of Jan. 1 being the closest of the year, it is not the brightest. Brightest-moon honors for 2018 go to the next full moon, on the morning of Wednesday, Jan. 31. That moon’s greatest brilliance will occur just before the eclipse, when the moon is just outside of Earth’s shadow and reflecting the greatest amount of light our way. During the total eclipse itself, we’ll also experience the faintest full moon of the year, cut off from direct sunlight by the Earth’s shadow.

Here is your guide to the “blue” moon (the second full moon of a calendar month, by one definition) and total lunar eclipse, on the night of Tuesday, Jan. 30, and Wednesday, Jan. 31. Keep in mind that because of the mountains surrounding the Coachella Valley, rising times may be later and setting times may be earlier than the “ideal” times listed here. From many locations in the valley, the later stages of the lunar eclipse might be hidden behind mountains to the west.

If you can allot just a small amount of time to watch the eclipse, be in a dark place on Wednesday morning, Jan. 31, between 4:20 a.m. (the moon halfway into umbra) and 5:30 a.m. (mid-totality, when the moon in deepest eclipse). Dress warmly!

On Tuesday, Jan. 30, from Palm Springs, moonrise occurs at 4:37 p.m., with sunset at 5:16 p.m. Does the rising moon seem unusually large to you? It was closest to Earth earlier on Jan. 30, around 2 a.m. By 5:45 p.m., the moon is 12 degrees up in east-northeast to east, and Sirius, the brightest star, will be nearly 45 degrees farther to the right, in the east-southeast to southeast.

As twilight deepens, the entire Winter Hexagon becomes visible. Astronomical twilight ends at 6:41 p.m., and the sky in this brightly moonlit night will get no darker until the eclipse gets underway. As twilight ends, note Pollux 15 degrees above and a little left of the moon, and his twin, Castor, 4.5 degrees to the upper left of Pollux. By 7:30 p.m., the star Regulus, heart of Leo, is 10 degrees up, just north of east, and 24 degrees to the lower left of the moon.

In the hour between 10 and 11 p.m., use binoculars or a telescope to try to catch the Beehive star cluster—then a difficult target in a bright sky, only 2 degrees north of the full moon. We’ll have a very good look at the Beehive during tonight’s total lunar eclipse! By 11:15 p.m., the bright, golden orange star Arcturus is 10 degrees up in the east-northeast.

At 11:45 p.m., the moon reaches its high point in the sky, 16 degrees south of overhead. Notice how short your shadow is. By midnight, the star Spica in Virgo is 12 degrees up in the east-southeast. You can use the curved handle of the Big Dipper to locate Arcturus and Spica.

If you can still see Aldebaran above the mountains to your west at 12:38 a.m. (22 degrees up in the west), then from the same location, you will be able to view the moon at the start of total eclipse at 4:52 a.m.—because the totally eclipsed moon will very closely follow Aldebaran’s track across the sky, but nearly 4 1/2 hours later. If Aldebaran still appears above the mountains at 1:15 a.m., then you will be able to view the moon during its deepest total eclipse later that morning, at 5:30 a.m. If Aldebaran is still visible at 1:52 a.m., then from the same site you may be able to observe the moon at the end of total eclipse, at 6:08 a.m., provided the shadowed moon is bright enough to be seen in the brightening twilight.

At 1:52 a.m., can you spot Vega, only 4 degrees up in the northeast? For the rest of the night, it climbs higher, while Rigel, Aldebaran, Sirius and Betelgeuse will all set before 3:30 a.m., before the moon begins to enter the umbra, or dark central core of Earth’s shadow at 3:48 a.m.

By 2 a.m., bright Jupiter will be 10 degrees up in the east-southeast and 27 degrees to the lower left of Spica.

At 2:51 a.m., the moon will just begin to enter the penumbra, or outermost, lightest part of Earth’s shadow. At that time, with the moon’s disk just outside the shadow, the moon appears at peak brilliance, because it’s closest to being directly opposite to the sun without being in shadow. The outer portion of the penumbra is not detectable, and so duskiness at the moon’s eastern (upper left) edge won’t be noted for perhaps another half hour.

By 3:30 a.m., the penumbral darkening on the moon’s upper left edge will be noticeable. At that time, find Jupiter 25 degrees up in the southeast, and Mars 12 degrees to Jupiter’s lower left. Look for the red supergiant star Antares, heart of the Scorpion, within 9 degrees below Mars.

At 3:48 a.m., the moon begins to enter the umbra, or dark central core of the Earth’s shadow. The moon will then be nearly due west, 35 degrees up. Within a few minutes, a dark, noticeably curved circular edge of Earth’s shadow will project on the eastern (upper left) portion of the moon. At first, the shadow appears very dark, in contrast with the rest of the moon’s disk, still illuminated by partial sunlight.

By 4:19 a.m., Earth’s shadow reaches halfway across the moon’s disk. As more of the moon is immersed within the umbra, colors within the shadow become noticeable, from sunlight which has passed through Earth’s atmosphere and bent into Earth shadow toward the moon. The inner portion of Earth’s shadow is typically reddish in color, for the same reason that sunrises and sunsets appear reddened, and skies appear blue.

Soon after 4:30 a.m., watch for Saturn, just risen in the east-southeast, 32 degrees to the lower left of Mars, and 44 degrees to the lower left of Jupiter; and Altair, just risen about 10 degrees north of east.

Total eclipse begins at 4:52 a.m., when the moon becomes completely immersed within the umbra. At that time, the moon will be just north of due west, and 22 degrees up. The view will be stunning some 10 minutes earlier, while a narrowing bright crescent of sunlight still illuminates the west-southwest (lower) edge of the moon.

Near the start of total eclipse at 4:52 a.m., expect a large range of color and brightness on the moon’s disk. The outer edge of Earth’s shadow might be bluish or yellowish, with the inner portion a darker rusty or grey. Check against Danjon’s 5-point scale (L = 0 to L = 4) if you would like to rate and report the darkness and color of this lunar eclipse. Now is also the best time to use your binoculars to easily observe the Beehive star cluster, just 4 degrees to the lower right of the moon.

Astronomical twilight begins at 5:18 a.m., when the sun is 18 degrees below the eastern horizon. If you’re in a dark place, this is the best time for viewing the Milky Way. Look for the Cygnus Star Cloud about 20 degrees up in the east-northeast, within the Summer Triangle. Binoculars resolve the cloud into many stars! Look also for Saturn 9 degrees up in the east-southeast to southeast, 32 degrees to the lower left of Mars, and 25 degrees to the lower left of Antares. Arcturus will be just 15 degrees south of overhead.

Deepest eclipse occurs at 5:30 a.m., when the moon will be 10 degrees north of due west and just 14 degrees above the horizon.

As morning twilight continues to brighten, the totally eclipsed moon might fade into invisibility, depending on how dark the Earth’s shadow is during this eclipse. During some past total lunar eclipses, such as one I saw in December 1963, such little sunlight made it through our atmosphere into Earth’s shadow that the moon almost completely disappeared, even when high in a dark sky. That eclipse was preceded by a major volcanic eruption in Indonesia.

Total eclipse ends at 6:08 a.m., when the moon will be 15 degrees north of west, and just 7 degrees up. Jupiter will then be almost due south, 39 degrees up. Even if the totally eclipsed moon had previously faded into twilight, the moon partially emerged from Earth’s shadow may become visible again before it finally sets. In theory, someone on a high peak near Palm Springs would be able to view the sun and a partially eclipsed moon, simultaneously on opposite horizons, at 6:46 a.m.

If you miss the total lunar eclipse on Jan. 31, another will be visible from the Coachella Valley in just less than a year—during convenient evening hours. On Jan. 20, 2019, a 3.3-hour encounter of moon with Earth’s umbral shadow will begin at 7:34 p.m. PST, including a 62-minute totality starting at 8:41 p.m.

On Friday, Jan. 5, I will present a summary of the coming year’s sky events. The talk will be held at the Portola Community Center, 45480 Portola Ave., in Palm Desert. Doors open at 6:30 p.m. for refreshments, and the talk begins at 7 p.m.

The website of the Astronomical Society of the Desert at www.astrorx.org has a listing of our evening star parties at two locations. The primary, more accessible location is at the visitor center of the Santa Rosa and San Jacinto Mountains National Monument (on Highway 74, within four miles south of Highway 111 in Palm Desert). A session is scheduled there on Saturday, Jan. 20, from 5 to 8 p.m. Sawmill Trailhead, our high-altitude site (4,000 feet—wear warm clothes), will have a star party starting at dusk on Saturday, Jan. 13. The website includes maps and directions for both locations. Star parties can be cancelled in poor observing weather. See also the link to “Impromptu Star Parties.”

Also, check out the Sky’s the Limit Observatory and Nature Center in Twentynine Palms, at skysthelimit29.org.

To help you plan evening or morning planet viewing sessions during the year 2018, below is Jeffrey Hunt’s two-page graphic summary of moon and planet setting and rising times, relative to times of sunset and sunrise, exact for Palm Springs.

Wishing you clear skies!

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. He is now retired and enjoys providing sky watching opportunities for a variety of groups in the Coachella Valley. Robert D. Miller did graduate work in planetarium science and later astronomy and computer science at Michigan State University and remains active in research and public outreach in astronomy. Dr. Jeffrey L. Hunt, a retired planetarium director now living in the Chicago area, has taught astronomy and sky watching to all ages. He studied astronomy education at Abrams Planetarium at Michigan State University. Jeff writes an astronomy blog at jeffreylhunt.wordpress.com and can be followed on Twitter at @jeff_hunt.

Evenings during twilight in early December 2017 feature a half-dozen stars of first magnitude or brighter, including the Summer Triangle of Vega, Altair and Deneb well up in the west, getting lower as month progresses; Fomalhaut, mouth of the Southern Fish, in the south; and Capella, the Mother Goat star, ascending in the northeast, with red-orange Aldebaran, eye of Taurus, to its lower right.

Binoculars and an unobstructed view are needed to spot Saturn, with Mercury close to its lower left, very low in the southwestern twilight glow 2.8 to 2.3 degrees apart Dec. 1-3, some 40 minutes after sunset. But both sink lower each evening, with Mercury fading to the equal of Saturn by Dec. 3, and fading rapidly thereafter. Mercury passes inferior conjunction, nearly between Earth and the sun, on Dec. 12, and Saturn hides in conjunction on the far side of the sun on Dec. 21.

In evening twilight late in month—or later in the evening in early December—watch the eastern horizon for the rising of reddish Betelgeuse and blue-white Rigel. About midway between them, Orion’s vertical three-star belt confirms their identity as Hunter’s shoulder and foot.

Our morning chart (below) depicts the sky about 45 minutes before sunrise, but we advise you to begin viewing at least a half-hour earlier than that, to allow time to locate all the bright objects before they are drowned out in the brightening twilight. Steady Jupiter in the southeast is the most prominent object during the half-hour beginning 75 minutes before sunup. (Venus doesn’t rise until 45 minutes before sunrise on Dec. 1; 30 minutes before on Dec. 12; and only 15 minutes before sunrise on Dec. 23.) Binoculars are increasingly useful for spotting Venus before sunup on the last possible date before superior conjunction, beyond the sun on Jan. 9.

Next in prominence after Jupiter are twinkling blue-white Sirius in the southwest to west-southwest, until it sinks from view late in the month; golden Arcturus high in the east; blue-white Vega rising higher in the northeast; and Capella sinking in the northwest. Mercury, very low in the east-southeast to southeast, attains magnitude +1 by Dec. 20, and magnitude 0 by Dec. 24, and for the rest of month ranks second in brilliance, after only Jupiter, since Sirius has departed.

Other bright morning objects include the Winter Hexagon, which has Sirius and Capella marking its southern and northern vertices, and red Betelgeuse inside. But Rigel, Aldebaran, Sirius and Betelgeuse exit the morning sky in December, leaving only the upper arch of Procyon, Pollux (with Castor 4.5 degrees to its right, not shown) and Capella.

Regulus, heart of Leo, is high in the southwest to west-southwest following the Hex across the sky. I like to imagine Leo chasing his menu, which includes some beef (Aldebaran in Taurus), two dogs (Sirius and Procyon in Canis Major and Canis Minor), a mother goat (Capella in Auriga) and even some human fare (Rigel and Betelgeuse of Orion, the Hunter, becoming the Hunted; and Pollux and Castor, of Gemini, the Twins).

Following Regulus across the sky are Arcturus and Spica. The latter star marks the ear of grain in the hand of Virgo, the next zodiac constellation east of Leo. The zodiac constellations serve as hosts to the bright objects of the solar system, namely the sun, moon and planets.

On Dec. 1, dim red Mars appears just 3 degrees from Spica and 16 degrees to the upper right of Jupiter. Jupiter itself is 4 degrees west-northwest of the third-magnitude star Alpha in Libra on Dec. 1; within 1 degree of that star Dec. 18-26; and as close as 0.7 degrees from Alpha Lib on Dec. 21-23. On Dec. 31, Mars is 3 degrees to the upper right of Jupiter, and 20 degrees to the lower left of Spica. On the last morning of 2017, Alpha Lib lies nearly midway between the planets, 1.5 degrees from Mars and 1.7 degrees from Jupiter—a beautiful sight for binoculars! The star’s Arabic name, Zubenelgenubi, meaning “Southern Claw,” refers to its assignment to a larger early version of the Scorpion, the next zodiacal constellation east of Libra. The pairing of Jupiter with Alpha Lib on Dec. 22 is the first of a triple conjunction between them. Jupiter, retrograding, will pass closely north of the star on June 3, 2018, and then, after resuming direct (eastward) motion, will pass closely north of it a third time, on Aug. 15.

Mercury, pulling away from its inferior conjunction of Dec. 12, brightens rapidly in the morning sky and holds a steady 28 degrees to the lower left of Jupiter Dec. 21-27. Look 8 degrees to the upper left of Antares, heart of the Scorpion, Dec. 20-27. During Dec. 28-30, Mercury is 9 degrees to the left or lower left of Antares. On Dec. 31, Mercury is 31 degrees to the lower left of Jupiter and 10 degrees to the lower left of Antares. On New Year’s morning, Mercury reaches greatest elongation, 23 degrees from the sun. On the mornings of Jan. 6 and 7, Mars will appear only 0.3 degrees from Jupiter. Within a week later, on Jan. 13, Mercury will pass 0.8 degrees south of Saturn. Wouldn’t a good pair of binoculars to view these events make a great gift for a skywatcher?

December opens with a few brightly moonlit nights. On Saturday evening, Dec. 2, the moon rises 20 minutes before sunset and is nearly full. An hour after sunset, find the Pleiades 10 degrees to the moon’s upper left, and Aldebaran, whose name means “the Follower” (of the Pleiades), within 14 degrees below the Pleiades and 7 degrees to the moon’s lower left. The moon creeps closer to Aldebaran throughout that night. During morning twilight on Sunday, Dec. 3, use binoculars to spot Aldebaran very close to the moon’s upper left. A “supermoon,” the closest full moon of 2017, occurs at 7:47 a.m. that morning, just more than an hour after moonset in Palm Springs. The moon reaches its least distance from Earth just 17 hours later, at 12:46 a.m. on Dec. 4.

Moonrise early on Sunday evening, Dec. 3 (as seen from Palm Springs), occurs at 5:11 p.m. Although more than nine hours past full, the moon, rising 33 minutes after sunset, will be impressive. Note Aldebaran 8 degrees to the moon’s upper right.

After it’s full, moonrise occurs later each night: On Monday, Dec. 4 at 6:10 p.m.; on Dec. 5 at 7:13 p.m. (northernmost moonrise of the month); on Dec. 6 at 8:19 p.m.; on Dec. 7 at 9:25 p.m.; and on Dec. 8 at 10:30 p.m.

On Dec. 5, two weeks have elapsed since Nov. 21, when Earth passed between the sun and the Pleiades (Seven Sisters) star cluster. Starting on Dec. 5, the moon is well below the horizon at the end of evening twilight, nearly 1 1/2 hours after sunset, and the sky is then dark and moonless. Starting on the evening of Dec. 5, face east-northeast to east at dusk and watch the Pleiades emerge and ascend in the deepening twilight. The scene is well described in lines by Alfred Lord Tennyson.

After the full moon, you can follow its motion in the morning sky, averaging 13 degrees per day eastward through the constellations of the zodiac. Watch the waning gibbous moon pass 9 degrees south of Pollux on Dec. 6, and leapfrog over Regulus on Dec. 8 and 9. On Dec. 12, find the waning crescent moon 9 degrees above Spica. On Dec. 13, the moon is 4 degrees to the upper left of Mars and 9 degrees to the lower left of Spica.

The moon rises very late on the night of Dec. 13 (as a 13 percent crescent at 3:21 a.m. on Dec. 14), leaving the peak of the Geminid meteor shower, overnight on Dec. 13-14, excellent for viewing meteors. Best hours are from Wednesday at 9 p.m. until first light of dawn at 5:15 a.m. on Thursday, although a few long trails from meteors grazing Earth’s atmosphere might be seen anywhere in the sky as Castor, near the shower’s radiant, rises soon after 6 p.m.

On the morning of Dec. 14, perhaps after a few good hours of meteor-watching, look for the moon passing 4 degrees north of Jupiter. On Dec. 15, find the moon within 12 degrees to the lower left of Jupiter. On the 16th, the last easy old crescent moon will appear 23 degrees to the lower left of Jupiter. If you have a very good low horizon between east-southeast and southeast, use binoculars to find Antares rising 9 degrees to the lower right of the crescent moon in brightening morning twilight.

In case the sky is very clear just after 6 a.m. on the morning of Sunday, Dec. 17, we have a site selected in northwestern Palm Springs to attempt a sighting of a very old moon, just a little more than 16 hours before new. We’ll announce the details in the “Impromptu Star Parties” link mentioned below.

We’re still checking out sites in Desert Hot Springs and the eastern Coachella Valley to attempt a sighting of a very young moon shortly after 5 p.m. on Monday, Dec. 18. The moon’s age will be just more than 18.5 hours. As the date draws near, visit the same link for details. Twelve days later, on Saturday, Dec. 30, the daytime waxing gibbous moon rising at 2:53 p.m. is covering Aldebaran. Telescopes may show the star emerging along the moon’s bright edge at 3:51 p.m.

The website of the Astronomical Society of the Desert, at www.astrorx.org, has a listing of our evening star parties at two locations. The primary, more-accessible location is at the Visitor Center of the Santa Rosa and San Jacinto Mountains National Monument (on Highway 74, within four miles south of Highway 111 in Palm Desert). A session is scheduled there on Saturday, Dec. 23, from 5-8 p.m. Sawmill Trailhead, our high-altitude site (elevation 4,000 feet—wear warm clothes), will have a star party starting at dusk on Saturday, Dec. 9. The society’s website includes maps and directions for both locations. Star parties can be cancelled in poor observing weather. See the link to “Impromptu Star Parties” on that website.

On Friday, Jan. 5, I will present a summary of the coming year’s sky events. The summer and early autumn of 2018 will be outstanding for viewing planets in the evening sky, and there will be total lunar eclipses in January 2018 and January 2019. The talk will be held at the Portola Community Center, 45480 Portola Ave., in Palm Desert. Doors open at 6:30 p.m. for refreshments, and the talk begins at 7 p.m.

Also, check out the Sky’s the Limit Observatory and Nature Center in Twentynine Palms, at skysthelimit29.org.

Wishing you clear skies!

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. He is now retired and enjoys providing sky watching opportunities for a variety of groups in the Coachella Valley. Robert D. Miller did graduate work in planetarium science and later astronomy and computer science at Michigan State University and remains active in research and public outreach in astronomy.

November 2017 features twilight planetary pairs—one in the morning, and one in the evening.

Venus and Jupiter will appear close together low in the east-southeast morning twilight glow for a few mornings around Nov. 13, about 40-45 minutes before sunrise. In last 10 days of the month, Saturn and Mercury will appear within the same binocular field low in the southwest evening twilight glow, 40-45 minutes after sunset.

Of the morning planets, dim, distant Mars rises in a dark sky all month, improving from 2.6 hours before sunup on Nov. 1, to 3.5 hours at month’s end. Mars glows at magnitude +1.8 to +1.7, about as faint as it ever gets. Brilliant Venus, of magnitude -3.9, rises in ever brighter twilight, 1.3 hours before sunup on the 1st, and about 45 minutes hour before sunup on the 30th. Watch for Venus’ rising 16 to 34 degrees to the lower left of Mars as November runs its course.

On Nov. 2, binoculars readily show the star Spica rising in the twilight glow 3.5 degrees to the lower right of Venus. The other morning planet, Jupiter, at magnitude -1.7, is lost in the sun’s glare well below Venus in first few days, but from Nov. 8-18, may be found in the same binocular field as Venus. The two bright planets appear closest on Monday, Nov. 13, with Jupiter just one-third of a degree to the upper right of Venus. This month, on Nov. 29, Jupiter will rise in a dark sky just more than two hours before sunrise. As Venus rises in twilight that morning, Jupiter will appear 17 degrees to the upper right of Venus and 17 degrees to the lower left of Mars, midway between them.

Bright stars in morning twilight feature the huge Winter Hexagon of bright stars moving into the west. Sirius, the Dog Star, is its brightest and southernmost member. Orion’s red Betelgeuse lies inside the Hex, and Leo’s Regulus, high in the south-southeast to south, trails behind it. Bright Arcturus in the east-northeast to east, and Spica in the east-southeast to southeast, round out the list of 10 stars of first magnitude or brighter visible in all of November’s dawns. An 11th star, Vega, rises in the northeast late in the month, far to the lower left of Arcturus.

Around Nov. 21, our Spaceship Earth is heading directly toward the star Regulus. Go outdoors in the morning, and visualize our planet’s motion around the sun, and the motions of faster-moving Venus, the next planet inside Earth’s orbit, and slower-moving Mars and Jupiter, the planets next outside our orbit. If we could look “down” from “above” the solar system, the planets would appear to revolve counterclockwise around the sun. All the morning planets are ahead of us. Venus is moving even farther ahead, and will pass on the far side of the sun in January 2018. We’re gaining on Jupiter and Mars, and will overtake them next year.

Bright stars in evening twilight in all of November include the Summer Triangle, with Vega, Altair and Deneb passing west of overhead; and Fomalhaut, mouth of the Southern Fish, low in the southeast to south-southeast. Quickly slipping out of view early in the month are Antares, in the southwest to the lower right of Saturn, and Arcturus, in the west-northwest. Rising into view are Capella in the northeast, and Aldebaran in the east-northeast.

Evening planets: Saturn (magnitude +0.5) on Nov. 1 sets in a dark sky 2.7 hours after sunset, and telescopes reveal its rings tipped as much as possible, 27 degrees from edgewise. But Saturn sets ever earlier, sinking close to brighter Mercury (magnitude -0.4 to -0.1) in the latter half of the month. Mercury appears to the lower right of Saturn, by 10 degrees on Nov 17, and 7 degrees on Nov. 20. On Nov. 23, Mercury reaches greatest elongation—22 degrees from the sun and 4.7 degrees below Saturn. Thereafter, Mercury appears to the lower left of Saturn, by 4 degrees on Nov. 24, and 3 degrees on Nov. 28. This is quite an unfavorable appearance for our solar system’s innermost planet, as it remains mired low in twilight.

The moon is full on Friday, Nov. 3, and rises north of east a few minutes after sunset. Two nights later, on Sunday, Nov. 5, the waning gibbous moon rises in the east-northeast within two hours after sunset. Using binoculars, look for the reddish-orange star Aldebaran, eye of Taurus the Bull, close to the moon’s upper right. That night, the moon will gradually creep eastward against the background stars, away from Aldebaran. By an hour before sunrise on Monday, Nov. 6, the moon and star will be in the western sky, with the moon 6 degrees above the star.

Follow the moon daily an hour before sunup. On Nov. 8 and 9, watch it leap over the line connecting the Twins (Pollux-Castor) to Procyon. On Nov. 11, it stops just short of Regulus, heart of Leo. That morning, binoculars will show Regulus just east of the fat crescent moon. As seen from Palm Springs through a telescope that day, the leading bright edge of the moon covers the star at 8:55 a.m., and the moon’s trailing dark edge, invisible in daylight, uncovers it at 10:01 a.m.

By Nov. 11, you’ll want to look low in the east-southeast 40 to 60 minutes before sunrise each morning for a week, to follow the progress of the Venus-Jupiter pair. That morning, Jupiter appears 1.9 degrees to the lower left of Venus. On Sunday, Nov. 12, Jupiter appears just 0.9 degrees directly below Venus. Their closest pairing occurs on Monday, Nov. 13, with Jupiter now only one-third of a degree to the right of Venus and slightly higher. Jupiter is getting higher each day, Venus lower.

On Tuesday, Nov. 14, Jupiter appears 1.3 degrees to Venus’ upper right. By that morning, you can find faint Mars 6-7 degrees below the moon. On Nov. 15, find the crescent moon within 7 degrees to the lower left of reddish Mars and within 7 degrees to the upper left of blue-white Spica, forming a beautiful triangle with them. Some 17-19 degrees to the moon’s lower left, find the Venus-Jupiter pair still within 2.3 degrees apart. On Thursday, Nov. 16, in possibly the prettiest scene, Jupiter and Venus are 3.3 degrees apart, within 6 degrees to the lower right and 9 degrees below the moon. On Friday, Nov. 17, the moon’s final morning, look about 40 minutes before sunrise to spot the very thin old crescent within 5 degrees to the lower left of Venus. Jupiter will be 4.4 degrees to Venus’ upper right. Since the new moon occurs the next day, Nov. 18, at 3:42 a.m., a sighting of the moon on the morning of Friday, Nov. 17 will be about 22 hours before new.

Start looking for the young moon in the early evening on Sunday, Nov. 19. About 40 minutes after sunset, find the thin crescent very low in the west-southwest, with Mercury about 8 degrees to its left and a little lower. Saturn will be 12 degrees to the moon’s upper left and 8 degrees to the upper left of Mercury. The moon’s age will be nearly 38 hours after new. On the following evening, Nov. 20, seeing the moon should be very easy, as it sets in a dark sky nearly two hours after sunset. You still need to look early in twilight to catch Mercury, 8 degrees below the moon. Saturn will be 2 degrees to the moon’s lower left.

On the night of Nov. 21, Earth passes between the sun and the Pleiades (Seven Sisters) star cluster. Within an hour after sunset that evening, face east-northeast—opposite to the sun’s direction below the west-southwest horizon—and watch the Pleiades emerge and ascend in the deepening twilight. The scene is well described in lines by Alfred Lord Tennyson.

To celebrate the occasion of the Venus-Jupiter pairing, members of the Astronomical Society of the Desert are offering sky watches on Monday, Nov. 13, and the next four mornings, as the crescent moon passes through the gathering of three planets and a star, and the Venus-Jupiter pair grows wider each day. The sessions will be held from 5:15 until 5:45 a.m., on the pedestrian bridge crossing over Tahquitz Creek, at Camino Real between North and South Riverside drives, three blocks north of Cahuilla Elementary School. The session is dependent on sky conditions. If the sky is clear, we’ll be there, with telescopes and binoculars.

The website of the Astronomical Society of the Desert has a listing of our evening star parties at two locations. The primary, more accessible location is at the Visitor Center (VC) of the Santa Rosa and San Jacinto Mountains National Monument (on Highway 74, within four miles south of Highway 111 in Palm Desert). Sessions are scheduled there on Saturdays, Nov. 25 and Dec. 23, from 5 to 8 p.m. Sawmill Trailhead (SMT), our high-altitude site (elevation 4,000 feet—wear warm clothes), will have star parties starting at dusk on Saturdays, Nov. 11 and Dec. 9.

This year’s Night Sky Festival at Joshua Tree National Park will be held Nov. 10-12. For details, visit www.nps.gov/jotr/planyourvisit/night-sky-festival.htm. Also, check out the Sky’s the Limit Observatory and Nature Center in Twentynine Palms, at skysthelimit29.org.

Wishing you clear skies!

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. He is now retired and enjoys providing sky watching opportunities for school children in and around Palm Springs. Robert D. Miller did graduate work in planetarium science and later astronomy and computer science at Michigan State University and remains active in research and public outreach in astronomy.

Rise early on these dark mornings, and you will be rewarded by a close planet pair, lots of bright stars, a star popping out from behind the moon, a meteor shower from Halley’s Comet, and a dust cloud in our solar system.

Evenings give us Saturn with rings now open to the max, and the Milky Way.

Our morning twilight all-sky chart for October 2017 at CVIndependent.com shows the changes in positions of naked-eye planets and stars of first magnitude or brighter at mid-twilight, when the sun is 9 degrees below the eastern horizon, some 40 minutes before sunrise. A bonus in October, while we’re still on daylight saving time: You don’t need to get up extra early by the clock to enjoy dark morning skies!

As the month progresses, stars will appear to drift from east to west along the tracks shown, owing to the revolution of Earth around the sun. Venus, of magnitude -4, still dominates the predawn sky. The chart shows Venus getting a little lower in the east each morning, because this swift inner planet is moving farther ahead of Earth and heading toward the far side of the sun, where it will arrive in January 2018, before emerging into the western evening sky.

Mars on Oct. 1 is only 2.5 degrees below Venus. The red planet now glows dimly at magnitude +1.8, as faint as it ever gets. But it plies its orbit more slowly than Earth, so we’ll gain on it, and it will appear higher each morning, passing only 0.2 degrees from Venus on Oct. 5, and climbing 16 degrees to Venus’ upper right by month’s end. Eventually, in late July 2018, Mars will appear low in the southwest at dawn (and in the southeast at dusk). The planet will then be at its closest to Earth since 2003, and up nearly all night, shining at magnitude -2.8.

Annually in October, the huge Winter Hexagon—in clockwise order from its brightest member, Sirius, Procyon, Pollux and Castor, Capella, Aldebaran and Rigel, with Betelgeuse inside—is well placed high in the sky before dawn. The flashing blue-white Dog Star Sirius is its most prominent and southernmost member. Sirius is the brightest star in Earth’s night skies, but it is much less bright than Venus. Capella, north or northwest of overhead, is the Hexagon’s second-brightest and northernmost member. Orion’s three-star belt (not shown) points to the lower left toward Sirius, and to the upper right toward Aldebaran, eye of Taurus, the Bull. Earlier, in darker skies, continue 14 degrees beyond Aldebaran to the striking Pleiades star cluster, beautiful in binoculars!

Far below the Hexagon is the second-brightest star in the heavens, Canopus. It reaches its high point just 4 degrees above the horizon due south at 5:30 a.m. on Oct. 16, near the start of morning twilight. But Canopus may not appear very bright, because much of its luster is lost during the last few miles of its beam of starlight coming in at a low angle through our atmosphere. Pick a very clear morning, and a place where mountains don’t block your view. I have seen this star from Palm Springs, looking through Palm Canyon in the Santa Rosa Mountains to my south. This far southern star reaches its high point 4 minutes earlier each day, 21 minutes before Sirius does, and 36 degrees lower.

Late in October, begin looking for bright, golden Arcturus rising in the east-northeast, and in the last couple of mornings, using binoculars, try for Spica in the same field as Venus. On Nov. 2, Spica will appear just 3.5 degrees to the lower right of Venus.

Morning moon wanderings: If you observe daily one hour before sunrise, then you’ll first spot the moon on Oct. 5, full and low in the west. Climbing steeply upward through the zodiac constellations day by day, the moon will appear 3-4 degrees to the lower right of Aldebaranon Oct. 9. Look through binoculars, and you may see several stars of the Hyades cluster, marking the face of Taurus, the Bull. On the next morning, find the moon 11 degrees to the upper left of Aldebaran.

The moon appears 11 degrees from Betelgeuse, Orion’s shoulder, on Oct. 10 and 11. On Oct. 12, the last quarter moon—half full and 90 degrees, or one-quarter circle, away from the sun—appears 10 degrees from Pollux, the brighter of the Gemini Twins, and 14 degrees from Procyon, the Lesser Dog Star. Look for Castor, the fainter Twin (not shown on the map), just 4.5 degrees north of Pollux.

Go outside shortly after 3 a.m. on Sunday morning, Oct. 15. When the 19 percent crescent moon rises at about 2:44 a.m., the star Regulus, heart of Leo, the Lion, will be hidden behind it! As the moon rises higher, the star will remain hidden for another half hour, until at 3:13 a.m., telescopes will show the star suddenly emerging at the dimly Earth-lit upper edge of the moon, then only 5 degrees above the horizon, and 11 degrees north of due east. By 5:30 a.m., the moon’s dim edge will be more than two-moon-widths from the star!

On Tuesday, Oct. 17, face east an hour before sunup to find a 5 percent crescent moon, with Venus 5-6 degrees below, and Mars 2 degrees to the upper right. On the next, final morning, Oct. 18, find the 2 percent, old crescent moon, 30 hours before new, 6-7 degrees to the lower left of Venus. The new moon, invisible in conjunction with the sun, occurs on Oct. 19 at 12:12 p.m. The morning sky thus becomes moonless, ideal for viewing the Orionid meteor shower at its best, in the dark predawn hours of Oct. 20-22. Orionids are dust particles originating from Halley’s Comet and might light up anywhere in the sky. Confirm a suspect meteor’s identity by extending its path backward past the start of its light-streak to a common origin, called the radiant. The true Orionids will appear to race away from the radiant in Orion’s club, north of Betelgeuse.

Another phenomenon excellent from very dark locations this time of year is the Zodiacal Light, reflected from comet and asteroid dust in the inner solar system. The best dates in the remainder of 2017 are Oct. 1, 2, Oct. 18-Nov. 1, and Nov. 17-30, about 90 minutes before sunrise. Look for a huge diffuse cone of light, broad near its base with its main axis near the ecliptic (marked by Regulus, the Beehive Cluster, Mars and Spica, after that star begins rising before morning twilight in November). Anza Borrego Desert State Park and Borrego Springs are fine places to observe the Zodiacal Light before dawn and the Milky Way after nightfall. This year, Oct. 19-22 would be an especially good time to visit; check out nightfallstarparty.com.

Our all-sky evening twilight chart for October shows the Summer Triangle of Vega, Altair and Deneb overhead, with Arcturus sinking low in the west to west-northwest, and Saturn with Antares 14-16 degrees to its lower right, in the southwest. Lonely Fomalhaut is in the southeast, in a rather barren area of the sky. Note the seasonal westward motions of the stars. The slow-moving outermost easy naked-eye planet Saturn, taking nearly 30 years to make one trip around the zodiac, gets dragged along with the stars’ seasonal motions. This month, telescopes show Saturn’s rings 27 degrees from edge-on, the maximum possible.

Arcturus is 33 degrees above the midday sun on Oct. 29, and is up nearly three hours longer than the sun, so for several days in late October and early November, you can catch Arcturus at two separate times: low in the east-northeast at dawn, and low in the west-northwest at dusk.

The first moon of the new cycle occurs on Friday, Oct. 20. Begin looking for the 2 percent crescent 6 degrees up in the west-southwest at civil twilight, when the sun is 6 degrees down, some 25 minutes after sunset, or 6:31 p.m. in Palm Springs and the western Coachella Valley. Mid-twilight (when the sun is 9 degrees down) occurs at 6:46 p.m., with the moon only 3 degrees up. To catch the 30-31 hour crescent, you’ll need to go to a place such as Desert Hot Springs or the far eastern Coachella Valley, where high mountains won’t block your view.

Within an hour after sunset on Sunday, Oct. 22, can you spot Antares 9 degrees to the lower left of the 10 percent crescent moon? On Monday, Oct. 23, the moon is in the southwest and 17 percent full, with Antares 12 degrees to its lower right and Saturn 6 degrees to the left. On Oct. 24, Saturn is 7 degrees to the moon’s lower right. The crescent is then nearly one-quarter full, but we must wait until the afternoon and evening of Oct. 27 to catch the first quarter moon, half full and 90 degrees east of the sun.

The website of the Astronomical Society of the Desert has a listing of our star parties. The primary location is at the Visitor Center of the Santa Rosa and San Jacinto Mountains National Monument (on Highway 74, within four miles south of Highway 111 in Palm Desert). Sessions are scheduled there on Oct. 28 from 7 to 10 p.m., and on Nov. 25 and Dec. 23, from 5 to 8 p.m. Sawmill Trailhead, our high-altitude site (elevation 4,000 feet—wear warm clothes), will have star parties starting at dusk on Sat. Oct. 14, Nov. 11, and Dec. 9. Also, check out the Sky’s the Limit Observatory and Nature Center in Twentynine Palms, at skysthelimit29.org.

Wishing you clear skies!

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. He is now retired and enjoys providing sky watching opportunities for school children in and around Palm Springs. Robert D. Miller did graduate work in Planetarium Science and later astronomy and computer science at Michigan State University, and remains active in research and public outreach in astronomy.

Our morning twilight all-sky chart for September, viewable below, shows the changes in positions of the naked-eye planets and the stars of first-magnitude or brighter, less than an hour before sunrise.

Changes are caused by the motion of the Earth and the other planets in their orbits. Stars will appear to drift from east to west across the sky as weeks pass, thanks to the revolution of Earth around the sun. Venus now dominates the predawn sky, but is getting a little lower each morning, because it is heading toward the far side of the sun, where it will arrive in January 2018.

Annually in September and October, the huge Winter Hexagon—in clockwise order from its brightest member, Sirius, Procyon, Pollux and Castor, Capella, Aldebaran and Rigel, with Betelgeuse inside—is well-placed high in the sky before dawn. The flashing blue-white Dog Star Sirius is its most prominent and southernmost member. Sirius is the brightest star in Earth’s night skies, but it does not appear as bright as Venus.

Morning planet gatherings: Low in the eastern morning sky in early September, Mars, Mercury and Regulus emerge to the lower left of Venus. Regulus, at magnitude +1.4, is the faintest of the first-magnitude stars. Mars is now even fainter, at magnitude +1.8, as dim as it gets—but Earth will catch up to it and close the gap. In July 2018, Mars will gleam at magnitude -2.8, visible all night, in the southwest at dawn (and southeast at dusk), and will be closer to Earth and brighter than at any time since the very close approach of August 2003.

On Sept. 4, Mercury, at magnitude +1.7, is a close match in brightness to faint Mars; they rise nearly at the same time, with Mars 3 degrees to the left of Mercury, and Regulus below them. Binoculars will show them in twilight about 17 degrees to the lower left of Venus, with the contrasting colors of reddish Mars and blue-white Regulus. All rise earlier each morning and get easier to see, especially Mercury, which brightens sharply, to magnitude +1.0 by Sept. 6; magnitude 0 on Sept. 9 and 10; and magnitude -1.0 on Sept. 18. Watch for these close pairs, all less than one degree apart: Mercury-Regulus on Sept. 10; Mercury-Mars on Sept. 16; Venus-Regulus on Sept. 18 and 19; Venus-Mars on Oct. 5; and Venus-Jupiter on Nov. 13. Binoculars will give a wonderful view of all these gatherings.

On Tuesday, Sept. 12, Mercury reaches a favorable greatest elongation, 18 degrees from the sun and 11 degrees to the lower left of Venus. Earlier on the same morning, telescopes show the moon covering and uncovering the first-magnitude star Aldebaran, eye of Taurus, the Bull. From Palm Springs, the star’s disappearance at the moon’s leading bright edge occurs just before 4:39 a.m., with reappearance at the trailing dark edge just after 5:53 a.m. Still earlier that morning, the dark edge of the moon uncovers a close pair of stars in the Hyades star cluster, at 1:31 and 1:38 a.m.

A few days later, on the mornings of Sept. 17 and 18, a waning crescent moon will appear near the Venus-Regulus pair, with the Mercury-Mars pairing below.

Follow the moon in evening sky: Careful viewers might spot a thin, young crescent moon very low in the west to west-southwest early on Thursday evening, Sept. 21, about 30 minutes after sunset, to the right of Jupiter. Find a spot without mountains blocking the view, and hope for very clear skies. It’ll be much easier to spot the crescent on the next evening, to the upper left of Jupiter. A much fatter crescent moon will pass the other giant planet, Saturn, on Tuesday evening, Sept. 26, with the twinkling reddish star Antares to their lower right. On the next evening, Sept. 27, the moon will reach first-quarter phase, 90 degrees or a quarter-circle east of the sun, and will appear half full. On Oct. 5, the moon will be full and will rise shortly after sunset, a little north of east, almost opposite to the sun’s direction in the sky.

Jupiter and Saturn are the slowest of the bright naked-eye planets. Jupiter takes nearly 12 years to make one trip around the sun, and Saturn takes about 29.5 years. Jupiter will pass 3.4 degrees north of Spica, the spike of grain in Virgo’s hand, on Sept. 11, and will return for a triple encounter with that star in 2029. Saturn appeared near Antares, heart of the Scorpion, in 2016, and will return to that star’s vicinity in 2045. Watch Jupiter creep slowly past Spica for several evenings around Sept. 11. Binoculars will help you pick up Spica to lower left of Jupiter as both sink into the twilight glow.

When the moon makes it around to Jupiter and Saturn from September 20-26, the planets will appear lower in the sky than they were early in the month, as shown on our all-sky evening twilight chart for September. So, if you’d like to enjoy telescopic views of both Jupiter and Saturn during an evening session, do it soon! (See a list of Astronomical Society of the Desert star parties at astrorx.org.) On these charts, note also the seasonal westward motions of Arcturus and the Summer Triangle of Vega, Altair and Deneb. The slow-moving outer planets seem to get dragged along with the stars’ seasonal motions.

To help you plan evening or morning planet-viewing sessions during the coming school year, see Jeffrey Hunt’s two-page graphic summary of moon and planet setting and rising times relative to times of sunset and sunrise—exact for Palm Springs—below.

Wishing you clear skies!

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. He is now retired and enjoys providing sky watching opportunities for school children in and around Palm Springs. Robert D. Miller did graduate work in planetarium science and later astronomy and computer science at Michigan State University and remains active in research and public outreach in astronomy. Dr. Jeffrey L. Hunt, a retired planetarium director now living in the Chicago area, has taught astronomy and sky watching to all ages. He studied astronomy education at Abrams Planetarium at Michigan State University. Jeff writes an astronomy blog at jeffreylhunt.wordpress.com and can be followed on Twitter at @jeff_hunt.

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