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Last updateTue, 18 Sep 2018 1pm

6:37 p.m. PST on Sunday, Jan. 20: The moon enters penumbra. The edge of the penumbral shadow will not be noticed, but the moon may seem especially bright then, because the moon most strongly reflects light back toward the source—the sun (and Earth, when the moon is just outside the Earth’s shadow). Look up opposition effect.

7:34 p.m.: Moon enters umbra. The moon begins to enter the dark central core of the Earth’s shadow. How long before this will you first notice the inner penumbral darkening on the moon’s east-southeast edge? How many minutes after first umbral contact will you notice the circular edge of the Earth’s shadow? When will you first notice any color within the shadow?

8:41 p.m.: Total eclipse begins. A few minutes before this time, the almost totally eclipsed moon, with a northwest-north-northwest narrow edge still in sunlight, is likely to be strikingly beautiful. Within the shadow, watch for reddish colors on the moon from sunlight which has passed through the Earth’s atmosphere and been refracted onto the moon. Use the 5-point Danjon scale and select the L number from 0 to 4, which best fits the description of the brightness and color of the moon in total eclipse. Use your own words to describe the eclipse! Repeat at greatest eclipse, and again at the end of totality. If you’re in a dark place during totality, enjoy views of the stars in the absence of bright moonlight. Look for the Beehive star cluster 6 degrees east of the moon.

9:12 p.m.: Greatest eclipse. The moon is closest to the center of the Earth’s shadow. Can you detect any color? Again, use the Danjon scale. Normally, we expect the eclipsed moon to appear darkest around this time. Note the “Twins” Pollux and Castor, 10-15 degrees to the upper left of the moon, and the “Little Dog” star Procyon, 17 degrees to the moon’s lower right.

9:43 p.m.: Total eclipse ends. Again, use the Danjon scale and your own words to describe the eclipse. Now, a few minutes after this time, when a narrow edge of direct sunlight illuminates the northeast edge of the moon, the nearly totally eclipsed moon is likely to be very beautiful.

10:51 p.m.: Moon leaves umbra, or dark central core of Earth’s shadow. How long after this time can you still notice any penumbral shading on the moon’s west-west-southwest edge?

11:48 p.m.: Moon leaves penumbra. You will not notice darkening near this time, but it is around this time we can expect the moon, just outside Earth’s shadow, to shine with extra brilliance. Adding to this opposition effect, the moon at perigee during this eclipse and the Earth-moon system being just a few weeks past perihelion (closest to Sun) combine to further increase the moon’s brightening.

• After January 20, 2019, the next total lunar eclipse visible in parts of U.S. will be on the morning of Wednesday, May 26, 2021; the total phase will be seen from all locations west of a line from east Texas/western Louisiana to eastern Montana. From California, the moon begins to enter umbra, or the dark central core of Earth’s shadow, at 2:45 a.m., followed by a brief, 15-minute totality from 4:11 a.m. until 4:26 a.m. The moon will then be low in the southwest, and morning twilight will be getting under way. The northern edge of the moon will be just barely within the umbra and should be noticeably brighter than the rest of the totally eclipsed moon. The star Beta in the head of Scorpius will be only two degrees north of the moon during totality. From the Coachella Valley, the moon will set a few minutes before completely exiting the umbra, but most of the California coast will be able to see the fully sunlit lunar disk for a few minutes after it departs from the umbra at 5:52 a.m.

• A very deep partial lunar eclipse (magnitude 97.4 percent) will be seen throughout the U.S. on the night of Nov. 18-19, 2021. From Western states, the moon enters the umbra at 11:19 p.m. on Thursday, Nov. 18. Greatest eclipse occurs at 1:03 a.m. early on Friday morning, Nov. 19. A very narrow brightly sunlit southern edge of the moon remains outside the umbra at greatest eclipse, while the rest of the disk shows dark grey or rusty brown hues. It should be a beautiful sight! At deepest eclipse, the Pleiades star cluster will be within 6 degrees north of the moon. The moon moves completely out of the umbra at 2:47 a.m.

• A deep total lunar eclipse will be seen from the contiguous 48 states on the night of May 15-16, 2022. Some western states will miss the start of the initial umbral phase, and northwest Washington state misses the start of totality. From Palm Springs and the Coachella Valley, the moon hasn’t risen yet when it begins to enter the umbra on Sunday, May 15 at 7:28 p.m. The eclipse is total for 85 minutes beginning at 8:29 p.m., during evening twilight. At deepest eclipse at 9:11-9:12 p.m., the northern part of the totally eclipsed moon should appear very dark as it passes through the center of the Earth’s shadow. As totality ends at 9:54 p.m., the moon is 11 degrees east of Alpha Librae and 7 degrees west of Beta Scorpii. Note the reddish (eclipse-colored?) star Antares, heart of the Scorpion, 14 degrees to the lower left of the moon. The concluding partial eclipse ends as the moon completely leaves the umbra at 10:55 p.m.

• A deep total eclipse on morning of Tuesday, Nov. 8, 2022 will be seen throughout U.S. For parts of the East Coast, the moon sets near the end of total eclipse. From California, the moon enters the umbra at 1:09 a.m. A long 85-minute totality, second of the year, occurs from 2:17 a.m. until 3:42 a.m. At deepest eclipse, at 2:59 a.m., the southern part of the moon should appear very dark as it passes through the center of Earth’s shadow. At the same time, Uranus, of magnitude 5.7, is easily seen in binoculars only 1.7 degrees to the upper left of the reddened moon; a telescope will reveal the planet’s greenish disk. The concluding partial eclipse ends at 4:49 a.m. as the moon completely leaves the umbra.

Published in Astronomy

The opening month of 2019 features outstanding sights for the unaided eye, as well as the eye aided with binoculars and telescopes.

Who would fail to wonder at the sight of brilliant Venus near a predawn crescent moon? Separated in time by about a month, we have close pairings on Jan. 1 and 31, providing two easy chances to locate Venus in the daytime with the unaided eye and binoculars. Telescopic views reveal Venus’ changing phase, from 48 to 62 percent this month, and its shrinking apparent size as the planet moves from the near side toward the far side of its nearly circular orbit around the sun.

Venus in January shines at magnitude -4.6 to -4.3, faded some since its peak in early December, but still at its best for 2019. Rising in a dark sky three hours or more before sun-up, it remains impressive!

Another astronomical highlight is a total lunar eclipse, on Sunday, Jan. 20, during convenient evening hours. The partial phase of the eclipse gets under way at 7:34 p.m. as the moon begins to encounter the umbra, or dark central core of Earth’s shadow. After several minutes, the curvature of the shadow’s edge will become obvious. At 8:41 p.m., the eclipse becomes total, and remains so for 62 minutes, until 9:43 p.m. A complete timetable of the eclipse appears on the January 2019 Sky Calendar (click link or see below; right click on the image and view in a new window), which also provides illustrations of that month’s outstanding planetary and lunar gatherings described in the following paragraphs. See also our separate article on the eclipse.

With the deepest total eclipse happening at 9:12 p.m. PST, should you encourage young children to observe this lunar eclipse? Well, if you miss this opportunity, the next chance to catch one during convenient evening hours won’t come until May 2022.

Planets at dawn: On New Year’s morning, Jan. 1, around 6 a.m. in the Coachella Valley, face southeast to enjoy a predawn lineup of the crescent moon with three planets to its lower left, in order: Venus, Jupiter and Mercury. Venus then is within 4 degrees to the lower left of the crescent moon, with Jupiter 18 degrees to the lower left of Venus; and Mercury 13 degrees to the lower left of Jupiter. When the moon reaches its highest point in the south, around 8:22 a.m. that day, Venus is an easy find within 3 degrees to the moon’s lower left—even though it’s daytime. Watch the waning crescent moon slide downward past three planets before sun-up Jan. 1-4.

On Thursday, Jan. 3, Jupiter appears 4 degrees to the upper right of the moon, while Mercury appears 12 degrees to the moon’s lower left. On Jan. 4, Jupiter appears 16 degrees to the lower left of Venus, while the thin old moon appears the same distance to the lower left of Jupiter, with Mercury, in turn, 2.5 degrees to the lower right of the moon. Mercury is getting lower each morning. Its departure after a few more days leaves two bright planets remaining. Masquerading as the two brightest “stars” in the entire predawn sky, the Venus-Jupiter pair becomes ever more striking as it closes to 10 degrees apart on Jan. 11, 5 degrees on Jan. 17, and a shortest distance of 2.4 degrees on Jan. 22. On the latter date, use binoculars to try to see Saturn just emerging from the morning twilight glow, 28 degrees to the lower left of the bright pair. Rising longer ahead of the sun and higher each morning, Saturn within a few days will become easy to see with unaided eye, and we’ll again see three naked-eye planets. From late January through mid-February, their arrangement from the upper right to the lower left will be Jupiter-Venus-Saturn. The waning crescent moon slides past this lineup, producing close pairings with planets on Jan. 30-Feb. 2.

The pairing of Venus and the crescent moon on Thursday morning, Jan. 31, will be unusually close and very striking, before dawn and for long after sunrise. From the Coachella Valley, the angular distance between Venus and the center of the moon’s disk will be just 1.5 degrees and closing at 5 a.m. By 6 a.m., the distance closes to 1.2 degrees. Sunrise occurs in Palm Springs at 6:43 a.m., with Venus just more than a degree from the moon’s center, or three-fourths of a degree from the moon’s edge. The closest approach of the moon and Venus occurs in daytime hours, between 9:45 and 10 a.m., with Venus about 0.4 degrees—less than the moon’s half-degree width—from the moon’s northern cusp (the upper point of the crescent). From 8:30 through 11:15 a.m., Venus will appear no more than a moon’s width from the moon’s edge. A telescope at low power will fit Venus and the moon in the same field, with Venus showing at gibbous phase, 62 percent illuminated.

At dusk: Mars is high in the south-southwest to southwest at dusk, halfway or more from horizon to overhead. Although fading slowly from magnitude 0.5 to 0.9, Mars shouldn’t be confused with any star while the red planet passes through the background of Pisces, which includes no stars brighter than magnitude 3.6.

In early January at dusk, the Summer Triangle of Vega, Altair and Deneb is still easy to see, with Vega and Deneb above in the northwest, and Altair in the west. Fomalhaut, mouth of the Southern Fish, is in the south-southwest, and the earliest stars of winter—Capella in the northeast to east-northeast, and Aldebaran in the east—are prominent. Although Aldebaran marks the eye of Taurus, its Arabic name means “The Follower,” of the Pleiades star cluster 14 degrees above it.

By early January, Orion’s Betelgeuse and Rigel, with his vertical three-star belt between them, have appeared above the eastern horizon. Two more of winter’s bright stars soon follow: Watch for their risings in twilight, by mid-January—first, Procyon in the east, and finally Sirius, the brightest nighttime star, in the east-southeast, below and in line with Orion’s belt. Sirius completes the nearly equilateral Winter Triangle with Procyon and Betelgeuse. When Sirius first appears low in the east-southeast, Altair is still visible, very low just north of west (if no mountains block your view), and both the Summer and Winter Triangles can be seen simultaneously.

The waxing moon returns to the early evening twilight scene as a thin crescent low in the southwest to west-southwest on Jan. 6; passes Mars on Jan. 12; skips past Aldebaran Jan. 16-17; and appears full to the lower right of the “Twin” stars Pollux and Castor on Sunday, Jan. 20, the same evening as the total lunar eclipse.

The website of the Astronomical Society of the Desert (www.astrorx.org) has a listing of our evening star parties at two locations. Sawmill Trailhead, our high-altitude site (elevation 4,000 feet), will have a star party starting at dusk on Saturday, Jan. 5. Our primary, more-accessible star-party site is 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 next monthly star party there is scheduled for Saturday, Jan. 12, from 5 to 8 p.m. Star parties can be cancelled in poor observing weather.

Also, check the Impromptu Star Parties link. I’ll be offering sky watches in Palm Springs at the pedestrian bridge over Tahquitz Creek at North Riverside Drive and Camino Real, including some in predawn to follow Venus’ conjunctions with the moon and other planets. Members of the Astronomical Society of the Desert may be offering a lunar eclipse watch at one or more locations on Sunday, Jan. 20.

On Friday, Jan. 18, I’ll present a preview of 2019’s sky events, including Sunday’s total lunar eclipse, and the year’s beautiful planetary gatherings. The talk begins at 7 p.m. at the Portola Community Center, 45480 Portola Ave., in Palm Desert.

Abrams Planetarium publishes a monthly Sky Calendar with an evening sky map. Subscriptions are $12 per year at www.abramsplanetarium.org/skycalendar for three printed issues mailed quarterly. The January 2019 issue of the calendar features the total lunar eclipse happening after nightfall on Jan. 20, and the four bright planets in the morning sky.

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.

Published 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.

Published in Astronomy

April 2014 at dusk: Jupiter is clearly the brightest “star” in evening twilight during April. Mars briefly equals or slightly outshines Sirius as the red planet passes opposition and makes its closest approach to Earth in the second week. Next in apparent brightness are Arcturus and Capella, high in the sky and easily seen. Slightly fainter Saturn rises in the east-southeast around mid-twilight at month’s end.

In the eastern half of the sky, Regulus, Arcturus and (barely) Mars are already up and ascending on April 1. As Earth passes between Mars and the sun on April 8, Mars is at opposition to the sun and visible all night. The same alignment occurs with the star Spica just five days later.

The moon forms striking gatherings with stars and planets during the first half of April. The waxing crescent will be a beautiful sight during the first few evenings in April as it climbs higher each night.

On Thursday evening, April 3, the moon will appear close to the lower right of Aldebaran, eye of Taurus, and among the stars along the right side of the “V” of the Hyades star cluster forming the Bull’s face. At 8:17 p.m., as seen from the Coachella Valley, the leading dark edge of the moon will occult, or cover up, the fourth-magnitude star Delta-3 Tauri, causing the star to suddenly blink out. The occultation will be best seen with binoculars or a telescope. Just more than an hour later, about 9:25 p.m., the star will reappear at the bright edge of the moon; it will not be as easy to observe the exact moment of its reappearance.

On Sunday evening, April 6, the moon, nearing first-quarter phase, passes 5 degrees south of Jupiter.On the next evening, the moon will be widely south of Pollux, one of the Gemini Twins, and on Thursday, April 10, it will pass widely south of Regulus, heart of Leo, the Lion.

During all of those evenings, the waxing moon will be tracking southof the ecliptic, or “below” Earth’s orbital plane—but that will come to an end late on the night of Monday, April 14, as the full moon returns close enough to our orbit plane to be completely immersed in the umbra, or dark central core of Earth’s shadow—causing a total lunar eclipse! (See below for information on a public viewing event.) The eclipse begins as the moon begins to enter the Earth’s umbra at 10:58 p.m.

The Earth’s diameter is nearly 3.7 times that of the moon, but the Earth’s shadow during this eclipse will appear only 2.7 times as large as the lunar disk. That’s large enough for the moon to easily fit, with plenty of room to spare!

As more of the moon is immersed in Earth’s shadow, the reddish color of the shadow will become noticeable. The reddish illumination is sunlight which has passed through the Earth’s atmosphere and gotten refracted into the Earth’s shadow. The total eclipse begins at 12:07 a.m., early on Tuesday morning, April 15.

The 78 minutes of total eclipse is a perfect time to use binoculars to locate the asteroids Vesta (magnitude 5.7) and Ceres (7.0), at peak brightness and just 2.4 degrees apart in Virgo, an easy star-hop from the dimmed moon and Spica. These asteroids are the destinations of the Dawn space mission; Dawn has already visited Vesta and is on its way to Ceres, arriving there in 2015.

Deepest eclipse occurs at 12:46 a.m., when the northern edge of the moon comes closest to the center of Earth’s shadow. Total eclipse ends at 1:25 a.m., and the moon’s withdrawal from the umbra will be complete at 2:33 a.m.

April 2014 at dawn: Venus continues to dominate the morning sky. Find it in the east-southeast in morning mid-twilight, drifting farther north as the month progresses. A telescope shows Venus in gibbous phase, fattening from 54 to 66 percent full, but shrinking in apparent size as it recedes from Earth. Saturn is a steady yellow “star” sinking slowly in the southwest. To Saturn’s lower right are bright reddish Mars and blue-white first-magnitude Spica, but they drop below the west to west-southwest horizon before month’s end, after passing opposition on April 8 and 13, respectively.

Other bright objects in the morning sky are golden Arcturus, well up in the west to upper right of Mars and Spica; reddish Antares, heart of Scorpius, in the south-southwest to southwest; and the Summer Triangle of Vega, Altair and Deneb high in the east, topped by its brightest member, Vega.

April’s waning moon, just hours after the lunar eclipse, is still close to Spica and Mars at dawn on the 15th. Early on the morning of the 17th, the moon passes closely south of Saturn, and on the 18th, the gibbous moon passes widely north of Antares. The last-quarter moon on the morning of April 22 will be 5 degrees northof the ecliptic, near stars marking the head of Capricornus, the Sea-goat. On the mornings of April 25 and 26, the crescent moon will appear near Venus. The new moon will occur on April 29.

Astronomical Society of the Desert Viewing

The Astronomical Society of the Desert will host a public viewing session for the total lunar eclipse on Monday night, April 14, starting at 10:30 p.m., at the Coachella Valley Preserve, 29200 Thousand Palms Canyon Road. Members will bring their telescopes to provide enhanced views of the eclipsed moon, as well as the three bright outer planets—Mars, Jupiter and Saturn.

Folks coming to the viewing session are encouraged to bring binoculars to enjoy the eclipse and the deep sky objects which will become visible as the sky darkens while the moon is increasingly covered by Earth's shadow.

During the total phase of the lunar eclipse, places far enough away from brightly lit cities will enjoy very dark skies. Vesta and Ceres, the two asteroids being visited by the Dawn Space Mission, will be easily seen in binoculars during the total eclipse.

For more information and directions, go to www.astrorx.org or call 760-771-4607. Bring the kids; it’s a great educational experience for them!

Robert C. Victor was a staff astronomer at the Abrams Planetarium at Michigan State University. He is now retired and enjoys providing skywatching opportunities for school children in and around Palm Springs.

Published in Astronomy