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Last updateTue, 18 Sep 2018 1pm

Robert Victor

From late January through most of February, early risers can enjoy all five bright planets before dawn. The waning moon sweeps past four of these planets Dec. 31-Jan. 7, and past all five Jan. 27-Feb. 6.

One hour before sunrise, find brilliant Venus in the southwest, with Saturn nearby to its upper right Jan. 1-8, and to the lower left thereafter. These two planets are 8 degrees apart on Jan. 1, closing to 5 degrees on Jan. 4. On two mornings, they’ll form a spectacular close pair in the same telescopic field, within 0.7 degrees, on Jan. 8, and 0.5 degrees on Jan. 9. They’re still within 4 degrees on Jan. 12, widening to 7 degrees on Jan. 15.

Each day, Venus goes east against background stars by just more than 1.2 degrees, while Saturn goes by only 0.1 degrees, and Mars goes east about 0.5 degrees. Watch Venus pass 6 degrees north of first-magnitude Antares, heart of the Scorpion, on Jan. 7, and 3 degrees north of a third-magnitude star marking the top of the Teapot of Sagittarius on Jan. 28. Steady Saturn is 6.3 degrees to 7.5 degrees from reddish twinkling Antares this month, and stays 6-9 degrees from that star throughout Saturn’s current apparition, which ends when the planet sinks into the evening twilight in November 2016.

Bright Jupiter, in the southwest to west-southwest an hour before sunup, barely moves against stars this month, but it will shift 10 degrees west over four months, Jan. 8 to May 9. This apparent temporary reversal of Jupiter’s motion is centered on the planet’s opposition and all-night visibility on the night of March 7-8. This retrograde motion is a consequence of the faster-moving Earth overtaking the giant planet.

Mars is in the south-southeast to south in this month’s morning sky, 6 degrees to 21 degrees east of Spica. On Feb. 1, Mars will pass 1.1 degrees north of third-magnitude Alpha in Libra. Once Mercury emerges from the sun’s glare in late January, all five naked-eye planets will be on display, in the order Me-Ve-Sa-Ma-Ju, in an impressive panorama across the southern morning sky. Mercury brightens from magnitude +1.2 to 0.0 at dawn in last 10 days of January, and continues to brighten into February.

Jupiter (magnitude -2.3 in mid-January) and Saturn (magnitude +0.5), with its ring system now tipped 26 degrees from edge-on, are favorites for telescopic viewing. They’re in the sky simultaneously mornings in the early months of 2016, and evenings from late spring into summer. Bright Venus (magnitude -4) in January shrinks to 0.2’ (arcminute) across, while increasing from 77 percent to 85 percent illuminated. Venus and Saturn appear within the same telescopic field on Jan. 8 and 9. Red Mars (magnitude +1.3 to +0.8) starts 2016 as a tiny disk 0.1’ across, nearly full. By opposition and closest approach in late May, Mars will triple in apparent size and match Jupiter in brilliance!

Follow the waning moon before dawn, near Jupiter, on Dec. 31, near Mars and Spica on Jan. 3, and near Venus, Saturn and Antares on Jan. 6 and 7.

Look for the moon within an hour after sunset each evening Jan. 10-23, as it waxes from crescent to full.

On Thursday, Jan. 14, Mercury is at inferior conjunction, as the planet goes between the Earth and the sun, while passing north of the solar disk.

In mid-January, the Summer Triangle of Vega-Altair-Deneb is visible at both dusk and dawn. Evenings, once Sirius has risen in the east-southeast, look for the Winter Hexagon of Sirius-Procyon-Pollux-Capella-Aldebaran-Rigel-Sirius, with Betelgeuse inside.

On Sunday and Monday, Jan. 17 and 18: Venus and Mars are 45 degrees apart in the morning sky. On Jan. 18, Ve-Sa-Ma-Ju span 90 degrees. Ma-Ju are 45 degrees apart.

Tuesday, Jan. 19: The moon’s leading dark edge, invisible in daylight, occults or covers Aldebaran, eye of Taurus the Bull, around sunset in the Coachella Valley. Times of star’s disappearance and reappearance for Palm Springs: 5:06 p.m. and 6:16 p.m. A telescope is best for viewing these events. After the star reappears, check at various times during the evening and watch the moon pull away from the star.

During Jan. 23-Feb. 7 in the morning sky, watch the waning moon go east against the zodiacal backdrop, posing near Regulus on Jan. 25 and 26, near Jupiter on Jan. 27 and 28, and just 4 degrees north of Spica on Jan. 30.

Illustrations of events mentioned above appear in the Sky Calendar. The sample excerpt on the next page depicts events such as the gathering of moon, Venus and Saturn on the mornings of Jan. 7-8. To subscribe, visit www.abramsplanetarium.org/skycalendar.

The Whitewater Preserve will host a star party on Saturday, Jan. 2, from 5 until 8:30 p.m. For information, call 760-325-7222.

To provide a chance for locals to view the unusual lineup of the moon and four or five planets, I will hold three predawn sky watches this month, if the sky is clear. The first will be held on the first clear morning of Wednesday, Jan. 6, or Thursday, Jan. 7, to view a compact gathering of the waning crescent moon with Venus and Saturn. The second will be held on the first clear morning of Friday, Jan. 8, or Saturday, Jan. 9, to view Venus and Saturn simultaneously within a telescope field. The third session will be held on the first clear morning of Sunday, Jan. 31, or Monday, Feb. 1, to view the lineup of all five naked-eye planets and the moon. All three watches will be held in Palm Springs, from 5:15 until 6 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 Astronomical Society of the Desert will host a star party on Saturday, Jan. 16, at dusk at the Visitor Center of the Santa Rosa and San Jacinto Mountains National Monument. More information is available at www.astrorx.org.

I will present a preview of sky events of 2016 on Friday, Jan. 29, at the Portola Community Center in Palm Desert. Socializing begins at 6:30 p.m., with the lecture at 7 p.m.

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. He is now retired and enjoys providing skywatching opportunities for school children in and around Palm Springs. Robert D. Miller, who provided the twilight charts and the planet orbit charts, 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 evening twilight in December, the Summer Triangle is well up in the west, getting lower as the month progresses. Its brightest member is blue-white Vega, at its northwest (lower right) corner. Altair marks the southern point of the Triangle, and Deneb the northeast corner, above Vega. Follow the Summer Triangle within the first hour after sunset until mid-January, when Altair sinks into the twilight glow.

Solitary Fomalhaut, marking the mouth of the Southern Fish, drifts low across the southern sky in December’s evening twilight. From late in December’s second week into early January, try to find Mercury very low in the southwestern twilight glow; binoculars make the search easier.

Yellowish Capella climbs in the northeast, while to its lower right, ascending in the east-northeast to east, we find red-orange Aldebaran, eye of Taurus the Bull. This star is at opposition to the sun each year around the start of December, so as we gaze at that star, we face almost directly away from the sun. Low in the east below Taurus, rising into view during twilight in late December, we find Orion’s two brightest stars: reddish Betelgeuse marking one shoulder, and blue-white Rigel marking his upraised foot. Robert Frost, in the opening lines of his poem “The Star Splitter,” described the scene: “You know Orion always comes up sideways. Throwing a leg up over our fence of mountains … .” Rising just a bit later from Southern California are Pollux and Castor above it, the bright stars of Gemini, the Twins.

In December’s morning twilight, Venus, in the southeast, ranks first in brilliance. Next is Jupiter, high in the southern sky. Third is twinkling Sirius before it sets in the west-southwest, and next is a nearly three-way tie between Arcturus very high in the east to southeast, Vega ascending in the northeast, and Capella sinking in the northwest.

Before Rigel sets south of west, look for the Winter Hexagon. In clockwise order beginning at Sirius, its other members are Procyon, Pollux (with Castor), Capella, Aldebaran, Rigel and back to Sirius, with Betelgeuse inside. At month’s end, all that remains of the Hexagon in morning twilight is an arch, in order from west to northwest: Procyon, Pollux (with Castor) and Capella.

Regulus marks the heart of Leo the Lion, chasing the Hexagon across the sky. Regulus is within 0.5 degrees north of the ecliptic (plane of Earth’s orbit). Following Regulus and in line with it is an almost straight lineup of the planets Jupiter, Mars and Venus, and finally Saturn, emerging in the southeast by the middle of December. Blue-white Spica, only 2 degrees south of the ecliptic, appears not far off the lineup of planets: Venus passed 4.2 degrees north of Spica on Nov. 29; contrastingly colored, dim, red Mars will pass 3.6 degrees north of that star on Dec. 23. By the latter date, Antares will have just emerged, some six degrees to the south (lower right) of Saturn.

One additional star appears on our December morning twilight chart: Deneb, rising in the far northeast late in the month, to the lower left of Vega.

Watch for these events:

Friday, Dec. 4, morning: Jupiter is 5 degrees to the upper right of the moon.

Saturday, Dec. 5, morning: Mars is 5-6 degrees to the lower left of the moon.

Sunday, Dec. 6, morning: Spica is five degrees to the lower right of the moon.

Monday, Dec. 7, morning: Spica is midway between Venus and Mars, 10 degrees from each. A spectacular close conjunction of the crescent moon and Venus occurs in morning twilight. Continue observing after sunrise and witness a daytime occultation of Venus by the moon. From Palm Springs, binoculars and telescopes show the leading sunlit edge of the moon covering Venus well up in the south-southeast to south at 8:09 a.m., with the trailing dark edge of moon (invisible in daylight) uncovering Venus well up in south-southwest at 9:59 a.m. Outside that interval, when Venus isn’t covered, this is a great chance to use the moon to help locate Venus in the daytime!Telescopes show Venus in gibbous phase.

I will hold three different sky watches, if the sky is clear, on the morning of Monday, Dec. 7: The first will be held from 5:15 to 5:45 a.m. to view the pairing in a dark sky before sunrise, as well to observe Jupiter, Mars and the bright stars; the next is from 8 until 8:10 a.m., to watch the bright edge of the moon cover Venus; and the last is from 9:55 to 10:05 a.m., to watch the invisible dark edge of the moon uncover Venus. All three watches will be held in Palm Springs, on the pedestrian bridge crossing over Tahquitz Creek, at Camino Real between North and South Riverside drives, three blocks north of Cahuilla Elementary School.

After Dec. 7, the waning moon can be followed for two or three additional mornings. On Thursday, Dec. 10, 40 minutes before sunup, try for the very thin old crescent, only 20-21 hours before new, very low in the east-southeast. Binoculars will be helpful for spotting it, and possibly emerging Saturn, rising within 3 degrees to the moon’s lower right.

Also watch for Saturn 6.2 degrees north of Antares (the minimum distance) on Monday, Dec. 21; Mars 3.6 degrees north of Spica (the minimum distance) on Wednesday, Dec. 23; and the moon 3 degrees to the lower right of Jupiter on the year’s final day.

Illustrations of these events appear in the Sky Calendar. For more information, visit www.abramsplanetarium.org/skycalendar.

The Astronomical Society of the Desert will host a star party on Saturday, Dec. 5, at dusk at Saw Mill Trailhead, at elevation 4,000 feet in the Santa Rosa Mountains. The society also hosts monthly star parties at the more conveniently located Visitor Center of the Santa Rosa and San Jacinto Mountains National Monument; the next is on Saturday, Dec. 19, from 5 to 8 p.m. Get more information at www.astrorx.org.

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. He is now retired and enjoys providing skywatching opportunities for school children in and around Palm Springs. Robert D. Miller, who provided the twilight charts and the planet orbit charts, 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 evening twilight during November, the holdover Summer Triangle, with its brightest member blue-white Vega at its northwest corner, drifts slowly westward from nearly overhead. Meanwhile, lonely Fomalhaut, mouth of the Southern Fish, moves from southeast toward the south. Bright Arcturus departs in the west-northwest, making way for almost equally bright Capella, rising in the northeast. Very low in the southwest to west-southwest, if mountains don’t block your view, Saturn and Antares (8 degrees to the planet’s left) are accessible with binoculars early in the month, before their departure.

Aldebaran, eye of Taurus the Bull, is at opposition as Earth passes between that star and the sun each year around Dec. 1; look for a reddish star rising in the east-northeast during twilight in late November. Arabic in origin, the name Aldebaran means the follower, alluding to the star’s pursuit of the Pleiades or Seven Sisters star cluster across the sky.

In November’s morning twilight, Venus, in the east to southeast, easily ranks first in brilliance. Next is Jupiter, climbing 6 to 34 degrees to Venus’ upper right and almost reaching south. The next dozen slots are taken by stars, headed by Sirius in the southwest, Arcturus climbing in the east-northeast to east, and Capella well up in the northwest. Sirius and Capella mark the southern and northern vertices of the Winter Hexagon. In clockwise order beginning at Sirius, its other members are Procyon, Pollux (with Castor), Capella, Aldebaran, Rigel and back to Sirius, with Betelgeuse inside. Regulus, heart of Leo the Lion, reaches its high point in the south while chasing the Hexagon across the sky. Following Regulus is the line of planets—Jupiter, Mars and Venus—and finally Spica, spike of grain in Virgo, rising up from low in the east-southeast to well up in the southeast. In late November and early December, watch for the rising of Vega far to the northeast. From its appearance until Rigel sets in west-southwest, 11 stars of first magnitude or brighter are visible, along with the three planets.

The moon and planets form spectacular gatherings, especially early in the month. Watch for these events:

  • Tuesday, Nov. 3, morning (about one hour before sunrise): Venus passes Mars. Look for the faint red planet just 0.7 degrees north (to the upper left) of brilliant Venus.
  • Friday, Nov. 6, morning: Jupiter is about 2 degrees north (to the upper left) of the moon. Venus is 10 degrees to the moon’s lower left. Mars is 1.6 degrees to the upper right of Venus.
  • Saturday, Nov. 7, morning: Venus is 1.7 degrees, with Mars 3.5 degrees, to the upper left of the moon. Venus and Mars are 2.1 degrees apart. Let the moon help you find Venus again after sunrise, and you’ll have a daytime sighting!
  • Monday, Nov. 9: Spica is within 4 degrees to the south (lower right) of the moon. Mars-Jupiter have spread to 10 degrees apart since their close pairing on Oct. 17.
  • Tuesday, Nov. 10, about 45 minutes before sunrise: The last, thin old crescent moon, 28 hours before new, rises in the east to east-southeast, 12 degrees to the lower left of Spica.
  • Thursday, Nov. 12, about half an hour after sunset: Binoculars may show a young crescent moon very low in the west-southwest, with Saturn 2-3 degrees to its lower left.
  • Friday, Nov. 13: This is the final morning Venus and Mars are within 5 degrees.
  • Friday, Nov. 22: This is the final morning Venus and Mars are within 10 degrees—and the first morning Venus and Spica are within 10 degrees.
  • Wednesday, Nov. 25 at dusk: Watch for Aldebaran rising 4 degrees to the lower left of the full moon in the east-northeast. Binoculars will help you see the star in moon’s glare throughout the night.

Watch the moon move! Early on Thanksgiving morning, the moon passes narrowly north of Aldebaran, without covering it. From our region, this happens around 2:48 a.m., when the star appears less than one-quarter of a moon’s width from the moon’s southern limb. Along a very narrow track from near the Oregon-California border across the U.S. to South Carolina, there will be a grazing occultation, as the star repeatedly disappears and reappears from behind mountains on the moon’s south limb.

  • On Thanksgiving, Nov. 26, in morning twilight, the moon is low in the west-northwest, with Aldebaran just more than a degree to its lower right.
  • On the mornings of Sunday, Nov. 29, and Monday, Nov. 30, Venus and Spica appear closest, 4.2 degrees apart.
  • Friday, Dec. 4, morning: Jupiter is 5 degrees to the upper right of the moon.
  • Saturday, Dec. 5, morning: Mars is 5-6 degrees to the lower left of the moon.
  • Sunday, Dec. 6, morning: Spica is 5 degrees to the lower right of the moon.
  • Monday, Dec. 7, morning: Spica is midway between Venus and Mars, 10 degrees from each. A spectacular close conjunction of the crescent moon and Venus takes place in morning twilight. Continue observing after sunrise and witness a daytime occultation of Venus by the moon. From Palm Springs, binoculars and telescopes show the leading sunlit edge of moon covering Venus at 8:09 a.m., and trailing dark edge of the moon (invisible in daylight), uncovering Venus at 9:59 a.m. Times vary with the observer’s location.

After Dec. 7, the waning moon can be followed for 2-3 additional mornings. Last chance: Thursday, Dec. 10, 40 minutes before sunup, a very thin old crescent, only 20-21 hours before new, is very low in the east-southeast. Binoculars will be helpful for spotting it. Try for emerging Saturn, rising within 3 degrees to the moon’s lower right.

Illustrations of events described in this article appear in the Sky Calendar. For a sample issue and to learn how to subscribe, visit www.abramsplanetarium.org/skycalendar.

The Astronomical Society of the Desert will host a star party on Saturday. Nov. 7, at dusk at Saw Mill Trailhead, elevation 4,000 feet in the Santa Rosa Mountains. The society also hosts monthly star parties at the more conveniently located Visitor Center of the Santa Rosa and San Jacinto Mountains National Monument. The next is on Saturday, Nov. 21, from 6 to 9 p.m. Dates of future star events, with directions and maps to the sites, are available at www.astrorx.org.

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. He is now retired and enjoys providing skywatching opportunities for school children in and around Palm Springs. Robert D. Miller, who provided the twilight charts and the planet orbit charts, 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.

During October and early November, there are exceptionally beautiful gatherings of planets in the morning sky. A waning crescent moon graces the lineup of planets on Oct. 8-11. Oct. 22-29, three planets will converge into a compact group, and on Oct. 25 and 26, the brightest of these, Venus and Jupiter, will pair very closely.

With daylight saving time still in effect through October, a brief sky watch about an hour before sunrise would provide a wonderful, rewarding display of planets at a time not unreasonably early.

Thursday, Oct. 8, one hour before sunrise: Venus gleams brilliantly within 3 degrees to the lower left of the crescent moon. Bright Jupiter shines 13 degrees to the lower left of Venus. Faint reddish Mars glows 4 degrees above Jupiter and 9 degrees to the lower left of Venus. Mercury, just beginning a morning apparition, rises in the east, within 19 degrees to the lower left of Jupiter. On the near side of its orbit, Mercury brightens rapidly and climbs higher in the coming days, but not high enough to meet any of the other planets.

This morning and tomorrow, note blue-white Regulus, heart of Leo, about 2.5 degrees to the upper left of Venus. This morning, students can follow the moon and Venus until sunrise and well beyond to catch Venus in the daytime. A telescope and even a steadily held pair of binoculars will reveal Venus as a crescent. Look an hour before sunup the next three mornings and follow the moon as it slides down the lineup of four planets.

Friday, Oct. 9: The moon appears lower and closer to the sun this morning, so today’s crescent is thinner than yesterday’s. Brilliant Venus is now 9 degrees to the moon’s upper right. Bright Jupiter is about 4.5 degrees to the lower left of the moon. Faint Mars appears within 4 degrees to the upper right of Jupiter and about the same distance north (to the upper left) of the lunar crescent. Can you spot Mercury very low in the east?

Saturday, Oct. 10: An old moon, just 2.5 days before new, is a very striking sight with the sunlit crescent cradling the earthlit darker side within its horns. Look for Mercury 10 degrees to the lower left of the moon, and Jupiter 9 degrees above the moon. Still higher, in order, are dim red Mars, brilliant Venus, and Regulus, to Venus’ upper left.

Sunday, Oct. 11: This is the last chance to see this thin crescent old moon in the morning sky. Just 35 hours before new, it’s a few degrees above the horizon and a few degrees south of due east. Mercury is 2 degrees to the upper left of the moon, 29 degrees to the lower left of brilliant Venus, and 18 degrees to the lower left of Jupiter. Faint Mars is a few degrees above Jupiter, while Regulus is a few degrees to the upper left of Venus. This week, watch Mars close in on Jupiter, while Venus widens its distance from Regulus. Mercury climbs to its highest point in the morning sky for this year late this week, but gets no closer than 28 degrees to the lower left of Venus.

Thursday, Oct. 15, one hour after sunset: Look low in the southwest to west-southwest to find the three-day-old waxing crescent moon, with Saturn 7 degrees to its upper left. Look also for reddish twinkling Antares, heart of the Scorpion, 10 degrees to the lower left of Saturn. By Friday evening, the moon will appear 6 degrees to the upper left of Saturn.

Saturday, Oct. 17, one hour before sunrise: Look closely for faint Mars just 0.4 degrees (less than a moon’s width) to the north (upper left) of Jupiter.

Oct. 22-29: Three planets—in order of brightness Venus, Jupiter and Mars—form a trio, appearing within a 5-degree field of view. Binoculars magnifying up to about 10-power will fit the trio in on these eight mornings.

Sunday, Oct. 25, and Monday, Oct. 26: Venus and Jupiter will appear just more than a degree apart, providing striking views, all within a single telescope field: Jupiter, with its four bright moons discovered by Galileo, and Venus appearing as a “half moon.” This sight should not be missed! The next pairings of Venus-Jupiter—at dusk on Aug. 27, 2016, and at dawn on Nov. 13, 2017—will be tighter, but low in twilight and will catch Venus on the far side of its orbit, displaying a tiny, nearly full disk.

Beginning Tuesday, Oct. 27, in morning twilight: Follow the moon daily for 15 mornings, as it wanes from full, low in the west on Oct. 27, to a thin, old crescent, low in the east-southeast, only 28 hours before new on Tuesday, Nov. 10.

Wed. Oct. 28, 45 minutes before sunrise: Mercury, now on the far side of its orbit, passes within four degrees to the north of emerging Spica. Use binoculars to see the star to the lower right of Mercury. Each morning, Spica appears higher in the sky (resulting from Earth’s revolution around the sun), with Mercury lower (because the inner planet moves faster than Earth).

Thursday and Friday, Oct. 29 and 30, one hour before sunrise: Watch the waning gibbous moon leapfrog past Aldebaran, eye of Taurus, the Bull.

Refer to the October 2015 Sky Calendar for illustrations of the gatherings described in this article. To subscribe online, visit www.abramsplanetarium.org/skycalendar.

The Astronomical Society of the Desert will host a star party, on Saturday, Oct. 10, at dusk at Saw Mill Trailhead, elevation 4,000 feet in the Santa Rosa Mountains. The society will resume monthly star parties at the Visitor Center of the Santa Rosa and San Jacinto Mountains National Monument on Saturday, Oct. 24, from 7 to 10 p.m. Dates of future star parties, with directions and maps to the sites and info on lectures and special events, are available at www.astrorx.org.

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. He is now retired and enjoys providing skywatching opportunities for school children in and around Palm Springs. Robert D. Miller, who provided the twilight charts and the planet orbit charts, 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.

Spectacular events in September include a close pairing of a waning crescent moon and Venus at dawn on Sept. 10—and a total lunar eclipse in the early evening on Sept. 27.

Venus now rises before the sun, and has become a spectacular morning “star” in the east before dawn. Venus reaches its greatest brilliance this year in the third week of September. Now through mid-October, the crescent phase of Venuscan be seen with just a pair of binoculars—just find Venus on any morning before sunup, and then eliminate the planet’s glare against a darkened sky by simply keeping track of it until sunrise or longer. The mornings of Sept. 10 and Oct. 8, with Venus near a crescent moon, are excellent opportunities to easily locate and observe Venus in the daytime.

Ranking next in brightness after Venus these morningsare the blue-white Dog Star Sirius in the southeast, and yellow Capella northwest of overhead. Look for the Winter Hexagon, in clockwise order from its lowest member: Sirius, Procyon, Pollux (and nearby Castor, not shown on the map), Capella, Aldebaran and Rigel. Folks checking the eastern sky regularly about an hour before sunrise can watch for the first appearances—called heliacal risings—of planets and first-magnitude stars. Regulus and Jupiter will emerge by mid-September.

During Venus’ reign as “morning star” through March 2016, the moon passes by the planet in our skies seven times. The first of these monthly events will be on Sept. 10, when, one hour before sunrise, Venuswill gleam in the eastern sky just 4 degrees to the upper right of a 7-percent sunlit crescent moon, graced by earthshine illuminating its upper non-sunlit side. About 6 degrees to the moon’s lower left is dim red Mars, and 9 degrees farther to the lower left is Regulus, heart of Leo, the Lion. Within 15 minutes later, look 6 to 7 degrees to the lower left of Regulus for Jupiter, just rising. The entire span of objects from Venus to Jupiter takes up just 23 degrees.

Venus on the morning of Sept. 10 appears three-quarters of an arcminute in diameter, compared to the moon’s 30 arcminutes, or half a degree. So viewed through a telescope at 40-power, Venus will appear as large as the moon does to unaided eye! The crescent Venus, then 18 percent sunlit and nearing greatest brilliancy, will be very striking. As morning twilight brightens, the crescent Venus will be resolvable even with 7-power binoculars, and easy to find 4-5 degrees to the moon’s upper right. Predawn or daytime, Thursday, Sept. 10, will be an impressive morning for outdoor astronomy!

Evenings: Golden Arcturus in the west, and blue-white Vega nearly overhead, shine as the brightest stars at dusk. Altair and Deneb complete the Summer Triangle with Vega. The moon can be followed one hour after sunset daily from Sept. 15-28, as it waxes from a thin crescent, through first-quarter phase (half full and 90 degrees east of the sun), to one day past full. Steady Saturn remains in view in the southwest at dusk, and appears not far from the reddish twinkling first-magnitude star Antares, heart of the Scorpion, and outshines that star by half a magnitude. Through a telescope, we get fine views of Saturn’s rings.

On Sept. 15, the moon will be 3 degrees up in the west-southwest 45 minutes after sunset, with Spicavisible in binoculars 3 degrees to moon’s lower left.

For the next 12 evenings, look nightly for the moon within an hour after sunset, and watch it change its phase (fraction illuminated) and move toward the place where it has an encounter with Earth’s shadow on Sept. 27.

On Friday, Sept. 18, an hour after sunset, the crescent moon is in the southwest, with Saturn just 2 degrees to its lower left. Note the red supergiant star Antares, heart of the Scorpion, twinkling 12 degrees farther to the left of Saturn, and a little lower.

The next evening, Saturday, Sept. 19, the fat crescent moon is 9 degrees nearly directly above Antares, while Saturn is 12 degrees to the right of the other two bodies, forming an isosceles triangle. On Sunday evening, Sept. 20, the moon is in the south-southwest one hour after sunset, 17 degrees to the upper left of Antares, and 87 degrees (nearly a quarter of a circle) east of the sun. This evening, the moon is nearly at first-quarter phase and appears slightly less than half full.

On Sept. 20, there is just one week to go until a very special full moon: Early in the evening on Sunday, Sept. 27, there will be a total eclipse of the harvest moon. The partial eclipse will already be under way as the moon rises in the east, just before sunset. Excessive media hype will be given to this eclipse, because it coincides with a so-called “Supermoon,” the closest moon of the year. The moon will be in total eclipse from 7:11 p.m. to 8:23 p.m. Pacific, and the partial eclipse will end at 9:27 p.m.

This full moon is both the faintest of the year (when deepest in Earth’s shadow at 7:47 p.m.) and the brightest (around 10:23 p.m., when just outside the penumbra of Earth’s shadow). Stand between a bright light and a reflectorized road sign so that the shadow of your head is cast upon the sign, and you’ll see a brilliant halo around your head’s shadow. The moon’s surface reflects light in the same manner as the reflectorized sign—very strongly back toward the direction of the light source.

On the next few evenings after the eclipse, you can witness moonrise nightly until it occurs too late for convenient viewing. By Oct. 2, moonrise occurs nearly four hours after sunset.

You can also convenientlyobserve the moon daily about one hour before sunrise beginning Sept. 28, the morning after the eclipse, through Oct. 11. On Oct. 2, the moon will occult Aldebaran after sunrise, covering and uncovering the star at about 6:44 a.m. and 7:18 a.m. in the Coachella Valley—both events visible through a telescope.

Be sure to check the schedule of monthly star parties, observing sessions for special events, lectures and more from the Astronomical Society of the Desert at www.astrorx.org. Also: Subscribe to the Sky Calendar online, at 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 skywatching opportunities for school children in and around Palm Springs. Robert D. Miller, who provided the twilight charts and the planet orbit charts, 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.

Jupiter sets almost an hour after the sun on Aug. 1, and three minutes earlier each evening thereafter. Using binoculars a half-hour after sunset, look very low, about midway between west and west-northwest, to the left of the sunset point.

If you can still find Jupiter on Aug. 5, try for Mercury, 1.9 degrees to its lower right. On Aug. 6, Mercury is 0.6 degrees to the upper right of Jupiter, and on Aug. 7, it is 1.4 degrees to Jupiter’s upper left. The solar system’s largest planet will be hidden for several weeks while it passes conjunction on the far side of the sun on Aug. 26. Meanwhile, Mercury makes a very low evening appearance, 4 degrees above the western horizon in mid-twilight (about 40 minutes after sunset) from Aug. 18 to Sept. 4, staying at magnitude 0 while shifting from 3 degrees north of west to 10 degrees south of west. Jupiter will emerge into the morning sky in September, joining Venus and Mars to form a spectacular compact trioin late October.

Venus passes inferior conjunction, nearly between Earth and the sun, 8 degrees south of the sun’s disk, on Aug. 15. On the morning of Aug. 17, Venus rises 8 degrees to the right of the sun, simultaneously with it. On Aug. 21, Venus rises 30 minutes ahead of the sun; on Aug. 26, just more than an hour before sunup; and by Aug. 30, Venus rises spectacularly in a dark sky 90 minutes before the sun.

Use binoculars or a telescope to observe its thin crescent phase, while avoiding the planet’s glare against a dark sky. Once you start seeing Venus in the morning sky in late August, just keep track of it until sunrise, and you’ll have a daytime sighting of Venus! This “morning star” will be most interesting through binoculars and telescopes from late August through late October.

If you enjoy the simple pleasure of watching the moonrise over a distant landscape, here’s when to look from the mid-Coachella Valley: On July 31, the full moon rises at 7:59 p.m., less than a quarter-hour after sunset. On Aug. 1, moonrise occurs at 8:44 p.m., within an hour after sunset. On Aug. 2, the moon rises at 9:26 p.m., just after the end of twilight. For the next few days, the moon rises about 40 minutes later each evening. By Aug. 4, the moon comes up at 10:47 p.m., three hours after sunset, allowing a nice window of dark skies before moonrise for enjoying the summer Milky Way. Note the summer triangle of Vega, Altair and Deneb plotted on August’s twilight sky charts. On moonless nights, look near the center of the summer triangle for the Cygnus Star Cloud—a bright patch of the Milky Way, containing stars within our own spiral arm. On dark nights, binoculars easily resolve the Cygnus Star Cloud into stars.

Returning to the sky in evening mid-twilight, we notice that Venus, so prominent in July, is absent; Jupiter is present only early in the month; and Mercury hugs the western horizon after Jupiter has departed. That leaves Saturn as the brightest object less than halfway to overhead. Find it in the south-southwest to southwest at dusk, with reddish twinkling Antares, heart of the Scorpion, 13 degrees to its lower left in all of August.

The rings of Saturnare now tipped 24 degrees from edge on. On evenings in August, Earth is in position to allow our best view of the shadow of the planet cast on the rings, giving the scene a beautiful 3-D appearance. Telescopic views are impressive! View Saturn and many deep-sky objects on Saturday, Aug. 15, at the Astronomical Society of the Desert “star party” at Sawmill Trailhead. For additional information, directions and a map, visit www.astrorx.org.

Golden Arcturus, high in the western sky, and blue-white Vega, high in the northeast, both outshine Saturn. Look also for Spica in the southwest, to the lower left of Arcturus and west (lower right) of Saturn.

The moon can be followed in evening twilight daily, Aug. 16-29, as it waxes from a thin crescent, through first quarter phase (half full and 90 degrees east of the sun on Aug. 22), to full.

Mornings during the summer and fall of 2015 will be fascinating for sky watchers. Those who check the eastern sky regularly about an hour before sunrise can watch for the first appearances—called heliacal risings—of planets and first-magnitude stars. Procyon and Sirius will appear by mid-August; Venus before the end of August; Regulus and Jupiter before mid-September; and Arcturus and Spica by the end of October.

This is a great year for the Perseid meteor shower. The peak—in dark skies on the night of Aug. 12-13—nearly coincides with the new moon. Best viewing is from late evening until the first light of dawn. Meteors belonging to this stream could appear anywhere in the sky, since the stream is much wider than planet Earth. However, if you extend the meteors’ trails backward beyond where they light up in the Earth’s atmosphere, they will all streak away from a point in the constellation Perseus, below the “W” of Cassiopeia in the northeastern sky. As evening twilight ends, this radiant point is very low in the sky, resulting in meteors making long trails through Earth’s atmosphere nearly parallel to the ground. During the night, as the Earth rotates, the radiant climbs ever higher in the sky, and our part of the Earth turns more nearly broadside to the incoming meteors. So the count of meteors is expected to be highest just before the start of morning twilight on Thursday, Aug. 13.

Another peak of activity might be seen on the previous morning, Wednesday, Aug. 12. That’s because before noon that day, the Earth passes nearest to a trail of dust left by Comet Swift-Tuttle in 1862. (That comet is the source of material for the Perseid meteors.) If the stream is broad enough, we could see enhanced numbers of meteors on Wednesday morning, too.

Resource: Get a sample issue and subscribe online to the Sky Calendar at 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 skywatching opportunities for school children in and around Palm Springs. Robert D. Miller, who provided the twilight charts and the planet orbit charts, 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.

Galileo, more than four centuries ago, observed and described phenomena you can witness in the evening sky this summer, including the phases of Venus, the moons of Jupiter, the Milky Way, details on the surface of the moon, and more. The Discoveries and Opinions of Galileo, a selection of the scientist’s writings translated by Stillman Drake, is fascinating reading.

Venus and Jupiter are still easy to spot during evenings for most of July 2015, because they far outshine all nighttime stars. Venussinks lower in the evening sky in July while getting ever more interesting for telescopic observation: As Venus draws closer to Earth, it displays an ever thinner, more backlit crescent.

Jupiter lingers close to Venus during the final weeks of their joint appearance in evening sky. First, Jupiter appears to right of Venus, by 0.6 degrees on July 1, and 1 degree on July 2. On July 4, they’re still within 2 degrees, and on July 9, within 4 degrees, with Jupiter to the lower right of Venus. On July 13, Venus and Jupiter appear just 5 degrees apart. Even at the end of July, Venus and Jupiter are still within 6.5 degrees, but Venus will then set in bright twilight, very soon after sunset. The crescent phase of Venus can be resolved with just a pair of binoculars, by avoiding the planet’s glare against a darkened sky. The best occasions in 2015 are in the late afternoon or around sunset from mid-June until late July/early August, and around sunrise or soon afterward from late August until mid-October.

Saturn appeared at opposition to the sun and was up all night on May 22, as Earth passed between that planet and the sun. Now in the months following, Saturn remains visible in the evening sky, reaching its high point in the south about half an hour earlier each week, crossing due south at dusk in July. In this year’s observing season, steady Saturn appears not far from the reddish twinkling first-magnitude star Antares, heart of the Scorpion, and outshines that star by as much as a magnitude. Through a telescope, we get fine views of Saturn’s rings, now tipped 24 degrees from edge-on.

The moon can be followed one hour after sunset daily as it waxes from a thin crescent, through first-quarter phase (half full and 90 degrees east of the sun), to full, July 18 through Aug. 1.

In evening sky on July 14, Venus approaches to within 2.4 degrees below Regulus. That evening, Jupiter is 5.2 degrees from Venus, narrowly missing forming a trio (three objects within a 5-degree field). Do all three fit within the field of view of your binoculars? On July 17, 30 minutes after sunset, the young moon is very low, north of west, 11 degrees to the lower right of Venus and 8 degrees to the lower right of Jupiter. Venus and Jupiter are 5.8 degrees apart. On July 18, before sunset from California, during the 6 p.m. hour, Venus is 3/4 of a degree from the moon’s northern cusp (the upper right point of the crescent), and at sunset is still within 0.9 degrees of the moon’s northern cusp. Can you see Venus in the daytime? On July 19, note the triangle Venus-Jupiter-Regulus, 13 degrees to 18 degrees to the lower right of the moon. On July 22 and 23, look for Spica near the moon. The moon reaches first-quarter phase, half full and 90 degrees from the sun, on July 23. On July 25, the moon is 3 degrees to the upper right of Saturn, while Antares is 13 degrees to Saturn’s lower left. On July 26, Saturn is 10 degrees to the moon’s right, and Antares is 9 degrees below the moon.

In the morning sky in July, Mercury can still be spotted very low in the east-northeast an hour before sunup in first half of month. Look to the lower left of Aldebaran, by 9 degrees on July 1, increasing to 22 degrees by July 9. On July 11, two hours before sunup, find the waning crescent moon in the east, 11 degrees right of the Pleiades star cluster, itself a pretty sight for binoculars. On July 12, 75 minutes to 2 hours before sunrise, find the lunar crescent in the east to east-northeast, with Aldebaran, eye of Taurus, 3 1/2 degrees to 3 degrees to the lower left. Binoculars show, in the same field, the fainter more distant stars of the V-shaped Hyades star cluster, with the moon just within the southern point of the sideways “V”. On the next morning, July 13, 75 minutes before sunup, a thinner crescent moon appears 10 degrees to the lower left of Aldebaran. On July 14, catch a last view of the thin old crescent moon about 3 degrees up in the east-northeast, 45 minutes before sunrise. Using binoculars, try for Mercury rising 9 degrees to the moon’s lower left. Also on its way out, Mercury will pass superior conjunction, invisibly on the far side of the sun, on July 23.

Replacing Mercury by the third week of July will be Orion’s two brightest stars: Betelgeuse rising north of east, and Rigel rising south of east. Using binoculars, you spot them as early as July 14; they’ll get easier to see later in the month, as they rise nearly four minutes earlier each morning. Before month’s end, these two bright stars will be easy to see in the east to east-southeast an hour before sunrise, with Orion’s belt appearing as a vertical line of three stars midway between. On July 29 and 30, look much farther north and lower, in the northeast to east-northeast, for the Gemini twins: Castor and Pollux 4 1/2 degrees to its lower right. On those two mornings, fainter Mars (magnitude +1.7) passes 5 3/4 degrees south (lower right) of Pollux.

See them all on July 18, at the Astronomical Society of the Desert “star party” at Sawmill Trailhead in the Santa Rosa Mountains. Visit www.astrorx.org for more information.

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

Robert D. Miller, who provided the twilight charts and the planet orbit charts, 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.

Venus and Jupiter in the west are closing toward a spectacular close pairing on June 30, while Saturn climbs in the southeast in the early evening. These three naked-eye planets, all showpieces for telescopic observation, should make a star party in June an exciting affair—so we hope you can arrange to attend one!

Evenings: Venus and Jupiter are easy to spot until late July 2015, because they far outshine all nighttime stars.

In June and July, Venus sinks lower in the evening sky while increasing in brightness and getting ever more interesting for telescopic observation: On June 6, Venus reaches greatest elongation, 45 degrees to the upper left of the setting sun; as seen through a telescope around that date, the planet appears as a tiny “half moon.” In the next 10 weeks, as Venus draws closer to Earth, it displays an ever thinner, more backlit crescent.

Jupiter appears close to Venus in June and July, during the final weeks of their joint appearance in the evening sky. First, Jupiter appears to the upper left of Venus, within 20 degrees on June 1, narrowing to 10 degrees on June 14. From June 22 through July 13, Venus and Jupiter will appear no more than 5 degrees apart, both easily fitting together within the field of view of binoculars magnifying no more than about 10-power.

Venus and Jupiter will form a spectacular close pair on June 30, just 0.3 degrees apart. A telescopic view of the planet pair that evening will be a memorable sight, not to be missed: Venus as a brilliant crescent, one-third full, matching the dim, fully lit disk of Jupiter in apparent size! This coincidence occurs because Jupiter, with a diameter 12 times that of Venus, will then be 12 times as far away! On five consecutive evenings, June 28-July 2, the planet duo will be no more than 1.2 degrees apart, easily fitting within a telescope’s low-power field.

The crescent phase of Venus can be resolved with just a pair of binoculars, by avoiding the planet’s glare against a darkened sky: One of the best occasions in 2015 is in the late afternoon or around sunset, from mid-June until late July/early August.

Saturn, at opposition to the sun on May 22 as the Earth overtook that planet, was visible all night. In the months following opposition, Saturn will remain in the evening sky, reaching its high point in the south about a half-hour earlier each week until crossing due south at dusk in July.

The moon can be followed as it waxes from a thin crescent, through first quarter phase (half full and 90 degrees east of the sun), to full, and about a day beyond—through June 3; and June 18-July 2. Folks new to sky-watching may enjoy keeping a diary or logbook of their observations of the sky, recording the date, time, observer’s location, direction in which the objects were seen, and comments.

Note the final gatherings of the moon with Venus and Jupiter in the evening sky will occur at dusk on June 19-20, and again on July 18, when the moon will appear very close to Venus! On June 17, 30 minutes after sunset from Southern California, a thin moon is about 4 degrees up in the west-northwest, 27 degrees to the lower right of Venus. On June 18, one hour after sunset, get a first easy view of the young crescent moon, 16 degrees to the lower right of Venus and 13 degrees to the lower left of Pollux. Jupiter is just more than 7 degrees to the upper left of Venus. On June 19, the moon is 7 degrees below and a little left of Venus; Jupiter is 6.5 degrees to the upper left of Venus. On June 20, the moon is within 6 degrees of the lower left of Jupiter. Venus is within 6 degrees of the lower right of Jupiter. On June 21, Regulus is 6 degrees to the right of the moon. On June 23, the moon, approaching first quarter phase, is just more than halfway from Regulus toward Spica. On June 25, Spica is 3 degrees to the lower left of the waxing gibbous moon. On June 28, Saturn is just 2 degrees to the right of the moon; Antares is 13 degrees to the lower left of Saturn. On June 29, Antares is 9 degrees to the lower right of the moon. On June 30, don’t miss the spectacular conjunction of Venus and Jupiter, just 0.3 degrees apart.

By the way: Events of this kind are illustrated on the Abrams Planetarium Sky Calendar. Subscriptions are appreciated; get details at www.pa.msu.edu/abrams/skycalendar.

Another enjoyable pastime is to watch the western sky within an hour after sunset to try to follow the planets and bright stars until their latest possible dates. By the end of May, Rigel, Aldebaran, Sirius, and Betelgeuse had already disappeared into the western evening twilight glow. In early June, Procyon sinks from view, and later in June or in earliest days of July (depending on the observer’s latitude), Capella, Pollux and Castor depart. All these disappearances of stars occur annually, at the same times of the year, as a result of the Earth’s revolution around the sun.

Mornings: During the summer and fall of 2015, mornings will also be very interesting for sky-watchers. Those who check the eastern sky regularly about an hour before sunrise can watch for the first appearances of planets and first-magnitude stars. Aldebaran, follower of the Pleiades and rising 14 degrees below that pretty star cluster, will return by the end of June; Betelgeuse, Rigel, Pollux, Castor and Mars do so before the end of July; Procyon and Sirius appear by mid-August; Venus before the end of August; Regulus and Jupiter before mid-September; and Spica by the end of October.

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. He is now retired and enjoys providing skywatching opportunities for school children in and around Palm Springs. Robert D. Miller, who provided the twilight charts and the planet orbit charts, 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 May, four of the 16 stars of first magnitude or brighter visible from Southern California begin their annual leaves of absence, sinking into the western twilight glow.

In order of departure, they are Rigel, Aldebaran, Sirius and Betelgeuse. In June, Procyon, Capella and Pollux will follow—all the stars of the huge Winter Hexagon, with Betelgeuse inside.

It’s enjoyable and relaxing to look for these stars within an hour after sunset on clear spring evenings. Those who watch regularly are certain to notice the stars appearing lower each evening at the same stage of twilight, and eventually dropping out of view. This change is a direct consequence of Earth’s annual revolution around the sun.

As seen from Earth from late April through mid-July, the sun appears to move from Aries through Taurus into Gemini, causing these zodiac constellations and their neighbors to sink into the evening twilight glow, and, after several weeks, to reappear in the eastern sky at dawn. (Exception: Far northern Capella emerges at dawn before it leaves the evening sky.)

The moon and naked-eye planets provide additional spice for skywatchers. In early May 2015, as many as four planets can be viewed simultaneously by observers with unobstructed views toward the west-northwest and east-southeast. During May’s first week, Mercury shines near magnitude 0, and on May 6, reaches its greatest angular distance from the sun this time around, 21 degrees. Around that date, Mercury also attains its highest position for this year at dusk. The best time to find it may be nearly an hour after sunset; look about 22 degrees to the lower right of brilliant Venus. Also on May 6, find bright Jupiter 45 degrees to Venus’ upper left. On May 6, wait until almost an hour and a half after sunset, when Mercury is just 3 degrees up in the west-northwest. Then turn around to find Saturn at about the same height above the opposite horizon, in the east-southeast.

Look a couple of minutes earlier each evening until May 11, and you’ll find Mercury and Saturn 5 degrees above opposite horizons, 1.2 hours after sunset. But by then, Mercury has faded to magnitude +1.0, and it will fade further in the following days.

Much easier than catching four planets simultaneously in May 2015 is viewing three, and you can do so in all of May and well into July! The span of Venus-Jupiter-Saturn starts out 159 degrees long on May 1, shrinking through 150 degrees on May 9, 135 degrees on May 22, and to 125 degrees on May 31. Venus and Saturn, the endpoints of the lineup, are both 10 degrees up 2.5 hours after sunset on May 1, improving to 23 degrees up at a very convenient viewing time of 1.3 hours after sunset by end of May.

As a wonderful bonus, these three planets are the most impressive for telescopic observation:Venusstarting in gibbous phase, two-thirds full at the start of May, passing through half full in early June, through ever larger and thinner crescent phases as the planet draws closer to Earth; Jupiter, with its cloud belts, and its four bright satellites discovered by Galileo (as were the phases of Venus); and Saturn,with its amazing rings, now 24 degrees from edge-on!

Excellent views of these showpiece planets make this a superb time to schedule evening sky watching sessions—star parties! The Astronomical Society of the Desert will host a star party on Saturday, May 30, at the Visitor Center of the Santa Rosa and San Jacinto Mountains National Monument on Highway 74, about four miles south of Highway 111 in Palm Desert. For more info, including dates of and maps to locations of star parties planned for this summer, visit www.astrorx.org.

If you haven’t been following the 5-months-long approach of Venus to Jupiter in the evening sky, start now! Venus and Jupiter are 50 degrees apart on May 1, closing to 35 degrees apart on May 16, and 20 degrees on June 1. The gap between the two brightest planets continues to narrow, to 10 degrees on June 14, to 5 degrees on June 21—and only 1/3 of a degree apart on June 30.

Many moon and planetary events in the evening sky in May and early Juneare illustrated on the Abrams Planetarium Sky Calendar. A downloadable PDF of the May issue, with an evening sky map, may be reprinted and distributed free of charge. Go to www.abramsplanetarium.org/skycalendar.

On May 1 and 2 in evening twilight, watch the waxing gibbous moon leapfrog past Spica. The full moon occurs on the evening of May 3. On May 4-6, two hours after sunset, watch the waning gibbous moon go past Saturn and Antares.

The moon returns to the early evening sky on May 19, as a thin crescent low in the west-northwest, 21 degrees to 22 degrees to the lower right of Venus. Two days later, on May 21, the moon passes 9 degrees to the lower left of Venus, which now forms an isosceles triangle with Gemini’s “Twin” stars Pollux and Castor. Jupiter is now 30 degrees to Venus’ upper left. On May 23, the fat crescent moon appears 6 degrees to the lower left of Jupiter. Catch the half-full first quarter moon near Regulus on May 24, and a gibbous moon near Spica on May 29.

On June 1, the nearly full moon appears in the southeast near Saturn and Antares, while Venus aligns with Pollux and Castor in the west-northwest. That same evening, Jupiter appears 20 degrees to Venus’s upper left, with just 29 days to go until their spectacular conjunction on June 30!

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

Few people will choose to arise early to catch the start of the lunar eclipse on Saturday morning, April 4, when the spring’s first full moon begins to enter the umbra, or dark central core, of Earth’s shadow at 3:16 a.m. local time.

For the next 1.7 hours, more and more of the moon will be immersed in the Earth’s circular dark shadow, until the start of the total eclipse at 4:58 a.m. Even before then, the rusty color typical of the moon in deep eclipse should be noticed—at least in the lower part of the moon’s disk, closer to the center of Earth’s shadow. Totality lasts less than five minutes, as the northern (upper) edge of the moon barely passes within the outer edge of Earth’s umbra. There should be a pronounced difference in color and brightness between the top and bottom edges of the moon.

Totality ends by 5:03 a.m., after which the moon will gradually emerge from the shadow, with the eclipse concluding at 6:45 a.m. From the Coachella Valley, the moon sets several minutes before then, cutting off our view.

If you prefer to watch this early-morning eclipse for just an hour, I recommend from 4:30 until 5:30 a.m., centering on the deepest eclipse at 5 a.m. At mid-totality, the moon will be quite dim compared to a normal full moon, and observers in dark locations will get a spectacular view of the Milky Way.

Other bright objects of April mornings: Spica will be just 10 degrees to the upper left of the moon at mid-eclipse on April 4, with golden Arcturus high to their upper right. The next morning, on Easter Sunday, April 5, Spica will appear within 4 degrees below the moon, and on April 8, the moon will appear within 2 degrees to the upper right of Saturn, and 10 degrees to the upper right of twinkling Antares, the red supergiant star marking the scorpion’s heart. The waning gibbous moon moves through the predawn Milky Way April 9-11, and by April 12, it has passed last quarter phase and appears slightly less than half full. The last easy view of the waning crescent will be low in the east an hour before sunup on April 16, with another chance for binocular users a half-hour before sunrise on April 17, only 30 hours before the new moon.

The brightest “stars” in evening mid-twilight: In order of brilliance, they are: Venus, in the west to west-northwest; Jupiter, passing just south of overhead around midmonth; Sirius, in the southwest sky, bluish and twinkling, heading lower as the month progresses; Mercury, emerging from superior conjunction beyond the sun on April 9 to appear very low in the west-northwest to lower right of Venus starting around April 18; Arcturus,in the east-northeast to east, higher as month progresses; and Capella, high in the northwest.

This is a good month to follow the motion of Venus against background stars. During April 9-11, Venus passes within three degrees south of the Pleiades, or Seven Sisters star cluster,an especially beautiful sight for binoculars! On April 16-22, Venus passes Aldebaran and the Hyades cluster, those stars together making up the “V”-shaped head of Taurus, the Bull. Meanwhile Jupiter lingers within 5-6 degrees east of the Beehive all month. Use binoculars to find that star cluster.

On April 19, 40 minutes after sunset, the thin young crescent, 32 hours past new, will be low in the west to west-northwest. Binoculars may show Mercurywithin 8 degrees to the moon’s lower right; and dim Mars within 4 degrees to the upper left of Mercury, and within 5 degrees to the lower right of the moon. This is the same night Venuspasses closest north (7 degrees to the upper right) of Aldebaran. On April 20, the lovely crescent moon will be almost directly below Venus, within 9 degrees to the lower right of Aldebaran, and 9 degrees to the lower left of the Pleiades. On April 21, the moon climbs to 5 degrees to the upper left of Aldebaran, while Venus shines within 8 degrees to their upper right. Far to their lower right, dim Mars glows only 1.5 degrees to upper left of bright Mercury.

On Apr. 22, Betelgeuse, shoulder of Orion, is 10 degrees south (to the lower left) of the crescent moon, while Mercury and Mars appear closest to each other, 1.3 degrees apart, with fainter Mars to the lower left. This is the first evening emerging Mercury is higher than sinking Mars. They’ll be 2 degrees apart on April 23, while the moon is midway between Betelgeuseand Pollux, brighter of Gemini twins. On April 24, the fat crescent moon exits the winter hexagon nearly halfway from Procyon to Pollux. On April 25, the first-quarter moon, half full, is 9 degrees to the lower right of Jupiter.

On April 26, the moon is in waxing gibbous phase, 8 degrees to Jupiter’s lower left, and on the next night, April 27, it appears 4 degrees south of Regulus, heart of Leo, the Lion.

On April 30, Mercury passes within two degrees south of the Pleiades. (Use binoculars to see the cluster low in twilight so late in April.)

Mid-April is a good time to start keeping a checklist of bright stars seen each evening. Many bright stars are gathered in the western sky, including the huge winter hexagon. Striking changes in the visibility of stars will occur in the next several weeks, as a result of the Earth’s revolution around the sun. An observer’s log can be downloaded here.

The Astronomical Society of the Desert will host a public star party on Saturday, April 25, from 8 to 10 p.m. at the Visitor Center of the Santa Rosa and San Jacinto Mountains National Monument, on Highway 74. For more information and directions, visit www.astrorx.org.

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