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Last updateTue, 18 Sep 2018 1pm

Robert Victor

Three planets are easy to spot in the evening sky in early June, and two of them are real showpieces, if you happen to have access to a telescope: Jupiter, with its four satellites discovered by Galileo, and its two dark cloud belts; and Saturn, with its spectacular rings.

June 2014 at dusk: The six brightest starlike objects visible at duskare Jupiter (the brightest, of magnitude -1.9 to -1.8); Mars (magnitude -0.5 to 0.0); the stars Arcturus, Vega and Capella (all near 0.0); and Saturn (+0.2 to 0.4). (The lower the magnitude number is, the brighter the object.)

Stars appear to twinkle noticeably, because of the Earth’s atmosphere. The planets generally shine with a steadier light, because they are close enough to Earth to show a disk, at least when seen through a telescope. Each point of the planet’s disk twinkles like a star, but if you add up the light from all the points, the sum is relatively constant.

June’s easily observed evening planets include Jupiter, sinking nearly to the west-northwest horizon, preparing to depart; Mars,in the south to southwest; and Saturn, ascending in the southeast to south. Mercury now requires binoculars; it sinks into the bright west-northwest twilight glow very early in the month while fading sharply, from magnitude +1.4 to +2.1, June 1-5. When you see three or more planets widely spaced in the sky, as they are in June, notice how they seem to lie in a nearly straight line across the sky: A line from Jupiter to Mars extended points to Saturn.

In what remains of winter’s collection of stars, Procyon, the “Little Dog” star, departs in the west early in June; Capella, already low in the northwest at the start of June, exits as well. Pollux and nearby Castor, not quite of first magnitude and therefore not shown on our twilight chart, are the last bright winter stars lingering well into June; look for these “Gemini Twins” to the upper right of Jupiter. Regulus, heart of Leo, is in the west-southwest to west, to the upper left of Jupiter. Blue-white Spica, spike of wheat in the hand of Virgo, and golden Arcturus, the “Bear Guardian” star in Bootes, the Herdsman, pass their high points in the south. Reddish Antares, heart of Scorpius, ascends in the southeast. Altair rises north of east to the lower right of Vega and Deneb, completing the Summer Triangle with them, in time for the season’s beginning.

Follow the waxing moon in the evening sky as it passes near these planets and bright zodiacal stars:Jupiter on June 1; Regulus on June 3 and 4; Mars on June 7; Spica on June 8; Saturn on June 9 and 10; Antares on June 11; and Jupiter again on June 28—but this time with the moon very low in bright twilight.

For planet-watchers: Watch the bent line of Jupiter-Pollux-Castor straighten as June progresses. The “twin” stars are 4 1/2 degrees apart, and Jupiter passes 6 degrees to the lower left of Pollux at mid-month. Follow Mars closing in on Spica all month. On June 1, Mars and Spica are 14 degrees apart; on June 30, they’re within 6 degrees.

On July 5, the moon, just past first-quarter phase and a little more than half illuminated, will pass between Mars and Spica while they’re within 4 degrees. In a colorful pairing on July 13, the red planet will pass just 1.3 degrees north of the blue-white star.

June 2014 at dawn: Venus at magnitude -4 is the only naked-eye planet up in morning mid-twilight. This brightest morning “star” appears low in the east to east-northeast during June. Next in brightness are three stars, all of magnitude zero: golden orange Arcturus, setting in the west-northwest; blue-white Vega, just west of overhead; and yellowish Capella, low in the northeast, ascending as the month progresses.

Other stars: Altair and Deneb, joining Vega to complete the Summer Triangle overhead; Fomalhaut, low in the southeast to south; Antares, heart of Scorpius, setting in the southwest early in month; and Aldebaran, eye of Taurus, emerging below Venus late in the month.

The waning crescent moon in the morning sky passes near Venus on June 24, within 2 degrees, and well worth getting up early to see! Note the beautiful Pleiades star cluster (aka Seven Sisters) 6 degrees to the upper left of Venus on June 23-25. The thin old moon appears to the lower left of Aldebaran, eye of Taurus the Bull, on June 25. Venus will pass just 4 degrees north of Aldebaran on July 1. The view of Venus, Aldebaran and the Hyades star cluster in binoculars early that morning will be breathtaking!

Many beautiful sights await you this summer, in both morning and evening skies. Mark the date Aug. 18 on your calendar, to remind yourself to get up early for a spectacular close predawn pairing of the two brightest planets, Venus and Jupiter. The June through September issues of the Abrams Planetarium Sky Calendar will provide illustrations of the best gatherings. Those issues won’t be put online, but you can get information on how to subscribe at www.pa.msu.edu/abrams/skycalendar.

Check the website of the Astronomical Society of the Desert (www.astrorx.org) for dates and locations of “star parties,” where everyone is welcome to look through our telescopes at the moon, planets and “deep sky objects.” Our sky watches at the National Monument Visitor Center will resume in October, while our monthly sessions at Sawmill Trailhead, at 4,000 feet, continue all year.

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, Calif. Robert D. Miller, who provided the twilight charts, did graduate work in planetarium science and later astronomy and computer science at Michigan State University. He remains active in research and public outreach in astronomy.

May evenings are rich with bright stars: As many as 11 of the 16 brightest stars visible from the Coachella Valley can be viewed simultaneously in twilight—and this year, four of the five naked-eye planets will join the display.

On the night of Friday, May 23, there will bepossible outbursts of meteors as Earth passes through several trails of debris from a small comet. Outbursts could be short, with the peak likely between midnight and 1 a.m., Saturday, May 24. Although meteors from these outbursts could be seen anywhere in sky, if their paths are extended backward, they will radiate from a point to the lower left of the North Star, Polaris. You might like to camp out in a dark place on that Friday night, and keep watch for unusually slow meteors (only about 30 percent as fast as August’s Perseids) between 10:30 p.m. on Friday and 2 a.m. on Saturday. For more, visit the webpage of the International Meteor Organization.

May 2014 at dusk: The five brightest “stars,” in order of brightness, are Jupiter, Sirius (until it drops below the horizon), Mercury, Mars and Arcturus. (Mercury may not seem so bright, because it is seen in a brightly twilit part of the sky; its brightness fades below that of Mars on May 8, and that of Arcturus on May 21.)

At dusk for most of May, four of the five naked-eye planets are visible simultaneously! Jupiter (magnitude -2.0 to -1.9) descends in the west to west-northwest. Mars (-1.2 to -0.5) ascends in the southeast to south. Saturn, passing oppositionas Earth overtakes it on May 10, shines at +0.1 for most of May, while ascending from east-southeast into the southeast. Mercury, low in the west-northwest to the lower right of Jupiter at dusk, sets at or after mid-twilight beginning May 3, while shining at magnitude -1.5. The planet fades to -1.0 on May 8, to 0.0 on May 20, and to +1.2 on May 31.

As for stars, four of winter’s luminaries disappear below the western horizon during May. First to depart is Rigel, followed by Aldebaran, Sirius and Betelgeuse. Forming an arch above Jupiter, the stars Procyon, Pollux and Castor of Gemini, and Capella will linger into June. Far to the upper left of Jupiter, the star Regulus, heart of Leo, the Lion, is high in the south to well up in the west-southwest sky in May at dusk. Arcturus and Spica adorn the eastern half of sky in May’s evening twilight, and Vega rises in the northeast by mid-twilight after May’s first few days. Deneb and Antares are added later in month. Antares is at opposition and visible nearly all night on May 30.

The moon in the evening sky in May and early June passes nearAldebaran on May 1; Jupiter on May 3 and 4; Regulus on May 7; Mars on May 10 and 11; Spica on May 11 and 12; Saturn on May 13; Antares on May 15; Mercury on May 30; and Jupiter on May 31 and June 1.

May 2014 at dawn: The four brightest “stars” at dawn are Venus (magnitude -4), Arcturus, Vega and Saturn (mag. +0.1). Those who rise early and get outdoors to look at the sky before dawn are forward-looking people—literally! That’s because each morning, we are on the front side of the Earth with respect to our motion around the sun—facing directly out the front window of Spaceship Earth! This is a direct consequence of the Earth’s rotating on its axis in the same direction as our planet’s revolution around the sun: Counter-clockwise, as seen from the north side, or “above” our solar system.

Venus at dawn in May gleams brilliant in the east. Examine Venus through a telescope, and you’ll find it two-thirds full on May 1 to more than three-quarters full on the 31st. In the morning sky, Venus is ahead of us, and widening its distance from us daily, until it rounds the far side of the sun in October. Low in the west-southwest to southwest at dawn, we find Saturn at opposition to the sun on May 10 this year, and Antares, heart of the Scorpion, at opposition on the night of May 30-31. As we follow our orbit curving between the sun and these two bodies, they’ll drift toward the horizon. So will Arcturus in the west to west-northwest, and eventually, so will the Summer Triangle of Vega, Altair and Deneb, now overhead. Recently emerged Fomalhaut, mouth of the Southern Fish, is ascending in the southeast.

The moon in the mornings in May passes nearSaturn on May 14; Antares on May 15 and 16; and Venus on May 25.

Check the website of the Astronomical Society of the Desert for dates and locations of “star parties” where everyone is welcome to look through telescopes at the moon, planets and “deep sky objects.” Our final sky watch until October at the National Monument Visitor Center takes place Saturday, May 10, but our monthly sessions at Sawmill Trailhead, at 4,000 feet, continue all year.

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, 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.

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.

In early March 2014, as seen from the Coachella Valley, the three brightest “stars” visible at dusk all reach their highest points within a span of 21 minutes. In order of brilliance, they are Jupiter, passing within 11 degrees south of overhead; Sirius, the “Dog Star,” 40 degrees up in the south; and Canopus, “Great Star of the (far) South,” less than 4 degrees up when passing due south, about 21 minutes before Sirius does.

Canopus passes directly overhead for observers near latitude 53 degrees south—in other words, southern Argentina or Chile. But here in the Coachella Valley, you must choose your spot carefully, or the mountains might block your view.

From the western Coachella Valley, Canopus passes due south only 4 degrees up in a dark sky at 7:31 p.m. on March 1, and then four minutes earlier each day, to 7:03 p.m. on March 8, and then 7:59 p.m. on March 9—an hour later than you might expect because of our annual shift to daylight saving time. By March 12, the star reaches its high point only an hour after sunset. After a few more days, as the star’s “transit time” keeps backing up toward sunset, the sky will be too bright to catch it at its high point.

Other features of the early evening: A telescope shows up to four of Jupiter’s moons, discovered by Galileo in 1610. Jupiter, red Betelgeuse, and blue Rigel now lie in a nearly straight line pointing downward. Orion’s three-star belt (not shown on the chart) lies midway between those two stars and points the way leftward toward Sirius, and the opposite way toward Aldebaran, eye of Taurus, the Bull, and beyond to the beautiful Pleiades, or “Seven Sisters” star cluster (not shown). The huge Winter Hexagon, in counterclockwise order Sirius-Rigel-Aldebaran-Capella-Pollux-Castor-Procyon and back to Sirius, with Jupiter and Betelgeuse within, contains 8 of the 21 stellar objects of first magnitude or brighter (16 stars and five planets) ever visible from the Coachella Valley. Their constellations include a bull backing away from a charging hunter and his two canine followers, a pair of twins and a chariot driver with mother goat and three kids tucked under one arm.

Following this menagerie is Leo, the Lion, with the bright star Regulus marking his heart. The lion is chasing his dinner across the sky. Quite a menu!

By March’s end, Arcturus, the “Bear Guardian” star, pops up above the east-northeast horizon before mid-twilight. Follow the curve of the bear’s tail (the handle of the Big Dipper) to brilliant reddish Mars, about to rise just south of east, and to Spica, Virgo’s sheaf of grain, 5 degrees to Mars’ lower right within 16 minutes later. (On March 20, the first day of spring, Mars and Spica rise simultaneously in a dark sky about 1.8 hours after sunset. Before March 20, Spica rises first.)

The waxing moon can be spotted daily at mid-twilight in the first half of March. It first appears as an extremely thin crescent on Saturday, March 1. (Please see the separate article about old and young Moons of Feb. 28 and March 1, posted online.) From places with a good, low view near the Coachella Valley, while using binoculars, you might first spot the moon between 6:03 and 6:08 p.m., when the hairline crescent will be 4 degrees south of west and just 5 to 4 degrees above the horizon. The moon will be just more than 18 hours old after new moon, which occurs at 12 a.m. (midnight) at the start of March 1.

On the next evening, March 2, the crescent will be higher and very easy to spot with the unaided eye. Look for earthshine—illumination from sunlight reflected by the Earth onto the moon’s dark (non-sunlit) side. Watch the crescent thicken daily as it moves farther from the sun on each successive evening, passing the Pleiades star cluster at nightfall on March 6, and within 3 degrees above Aldebaran by the next evening. The moon reaches first quarter phase, half full and 90 degrees from the sun, between the evenings of March 7 and 8.

Finally, the full moon on Sunday, March 16, rises about 20 minutes after sunset, and at mid-twilight is 3 degrees up and 6 degrees south of east. You can continue following the moon for four more evenings by waiting for its rising about an hour later each night—or you can switch your viewing time to morning.

March 2014 at dawn: The brightest objects in morning twilight, in order of brilliance, are: Venus in southeast, slowly fading from its February peak brilliance, and now appearing as a roughly “half moon” through telescopes; Mars in the southwest to west-southwest; Arcturus high in the west; Vega high in the northeast; and Saturn in the south-southwest to southwest. Late in month, Mercury, low in the east-southeast to east, brightens to outshine Arcturus, but it drops very low in bright twilight as it approaches the far side of the sun.

Mars and Spica are 6 degrees apart on March 1, closing to 5 degrees on March 20, and to a least-separation of 4.8 degrees on March 25 and 26, in the second of three conjunctions within six months. Their final pairing, just 1.3 degrees apart, will occur in the evening sky on July 13.

Near Vega are Altair to its lower right, and Deneb to its lower left, completing the Summer Triangle.

To the left of the Mars-Spica pair lies a yellowish point of light glowing steadily: A telescope reveals the rings of Saturn, now tipped over 22 degrees from edge-on! Extend the Mars-to-Saturn line to the left of Saturn and drop down a bit, and you’ll find reddish twinkling Antares, heart of the Scorpion.

The moon can be followed in morning twilight in the latter half of March. It starts its journey as a full moon low in the west on March 16. Within a week, passing through the southwestern quadrant of the sky, it appears near Mars-Spica on March 18 and 19, near Saturn on March 20 and 21, and well above Antares on March 22. The moon passes last-quarter phase, half full, between the mornings of March 23 and 24. A waning crescent, the moon appears in a beautiful pairing with Venus in the southeast on March 27, and next, widely above and then left of Mercury on March 28 and 29. The last old crescent will appear very low, just south of east in bright twilight, on March 29. The second new moon of this month occurs on the 30th at 11:45 a.m.

Evening encore: The month ends as it began, with a beautiful young crescent moon low in the western sky at dusk. This one should be easy for unaided eye: Forty minutes after sunset, it will be 8 degrees north of west, 7 degrees above the horizon, and 32 hours old.

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, 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.

Author Fred Schaaf describes a very thin crescent moon in his book The 50 Best Sights in Astronomy and How to See Them

Recounting an early sighting of a very young moon, he writes that the moon was “thin as a single snippet of pale gold hair falling, falling gently through dusk to the repose of the low forest horizon,” and that it was “a slight but dreaming and luminous smile scarcely touching the face of that twilight sky, a face whose tender tones and shades were the only things which could possibly be delicate enough to hold the moon. … An indelible mark, a slenderest sliver of pure celestial beauty that eternity keeps forever from harm or slightest alteration.”

Here in the Coachella Valley and elsewhere in the U.S., there will be yet another rare chance to see not just one, but two unusually thin crescent moons, about 36 hours apart, on two consecutive days: at dawn on Friday, Feb. 28, and at dusk on Saturday, March 1. Binoculars will be a great help on both occasions. The astronomical new moon, invisible as it passes a few degrees north of the sun, occurs almost midway between the two sightings, at 12 a.m. (midnight) at the beginning of March 1.

Illustrations of the old crescent at dawn on Feb. 28, and of the young crescent at dusk on March 1, appear on the February 2014 Sky Calendar, available online at www.pa.msu.edu/abrams/skycalendar.

Valley residents can try for the old crescent on Friday, Feb. 28, between 5:46 a.m. and 5:56 a.m., when the very thin crescent will appear 11 to 12 degrees south of due east, rising slowly, from 2 degrees to 4 degrees above the horizon. That “viewing window” spans only from 30 minutes to 20 minutes before sunrise, so binoculars are recommended in the brightening twilight.

Planets might be helpful for locating the moon that morning. Venus will be very prominent, some 22 degrees up in the southeast, with fainter Mercury 22 to 23 degrees to the lower left of Venus. The moon can be found 12 degrees lower left of Mercury.

The young moon on Saturday, March 1, will best be seen in the Coachella Valley between 6:03 p.m. and 6:13 p.m., with the hairline thread of a crescent appearing from 4 degrees to 3 degrees south of due west, and sinking slowly, from 5 degrees to 3 degrees above the horizon. This viewing window spans from 20 to 30 minutes after sunset, so binoculars are again recommended for spotting the young crescent, which will be even thinner and closer to the sun than the old crescent of the morning before.

Seeing either one of these two crescent moons will require clear weather, and careful advance planning to make sure the line of sight from observer to moon will not be obstructed by local topography; after all, there are plenty of mountains around here which often block the view of events such as these!

From the Coachella Valley, different sites may well be required for the two sightings. You can increase your chances by checking out your viewing site in advance, by observing the moon at a date and time when it will have nearly the same position in the sky as the moon at the target date and time.

Here are directions for accurately predicting the positions of both the old and the young crescent moons at the middle time of each recommended 10-minute window.

The old moon (at dawn, 5:51 a.m., Friday, Feb. 28): Observe the waning gibbous moon on the evening of Monday, Feb. 17, at 8:38:15 p.m. (It will be 91 percent full and easy to observe if not hidden by clouds or local topography.) You will find it at azimuth 97.3 degrees (7.3 degrees south of due east) and altitude 3 degrees. When you look for the moon on Feb. 28 at 5:51 a.m., you’ll find it 4.3 degrees to the right of the spot where the moon appeared on Feb. 17 at 8:38:15 p.m.

For an even closer forecast of position, observe the 84 percent moon the next evening, Tuesday, Feb. 18, at 9:35:30 p.m., and you’ll find it at azimuth 102.3 degrees (12.3 degrees south of east), and altitude 3 degrees. Then when you look for the moon on Feb. 28 at 5:51 a.m., you’ll find it just 0.7 of a degree to the left of your Feb. 18 sighting.

The young moon (at dusk, 6:08 p.m., Saturday, March 1): Observe the 94 percent moon on the morning of Tuesday, Feb. 17, at 7:18:40 a.m. You’ll find it then at azimuth 264.7 degrees (5.3 degrees south of west), altitude 4 degrees. Then, to find the young moon on March 1, look just 1.7 degrees to the right of where you spotted the moon on Feb. 17.

What to look for when you observe a thin crescent moon: Can you see any illumination of the moon’s dark side? It’s called earthshine for a good reason: It is the moon being illuminated by sunlight reflected by the Earth. Usually, earthshine is not seen when the lunar crescent is very close to the sun, because the moon is immersed in the foreground bright twilight sky. For your best chance to detect earthshine on a very thin crescent, look soon after moonrise, before the sky gets too bright, or not long before moonset, when the sky has darkened sufficiently. But if the moon is very low, then Earth’s atmosphere will dim the light.

When you observe a very thin lunar crescent, note how much of the moon’s circumference you can see. It will help to visualize the moon’s disk as a clock face. When the crescent isn’t too close to the sun, an arc of 180 degrees is typical. But the arc of a crescent moon very close to the sun is noticeably shorter.

For example, on the morning of Feb. 28, if you perceive the moon’s circumference illuminated from 4 o’clock to 10 o’clock, then the sunlit arc would extend halfway around the clock face, and its length would be 180 degrees. But if you observe the sunlit arc only from 4 o’clock to 9 o’clock, then its length would be just 150 degrees.

Are there any breaks in the crescent, or any thin spots where only a thread of light makes the crescent continuous?

Note the times of your first and last observation of the crescent. Calculate the time interval between your sightings and new moon, which occurs at 12 a.m. at the beginning of March 1.

Alexander Seidler and I spotted opposing crescent moons on consecutive days, on Dec. 31, 2013, in morning twilight (an easy sighting for binoculars and unaided eye within 21 hours before new), and on Jan. 1, 2014 very early in evening twilight (a very difficult sighting, within 14 hours after new). Alex had not previously observed a crescent moon within 24 hours of new, and I had never before spotted opposing crescents on consecutive days. Read more about our sightings here.

From the Coachella Valley, the opposing pair of Feb. 28 and March 1 will be more balanced, with both crescents just more than 18 hours away from new. The morning crescent, though farther from the sun, will be less favorable for viewing, rising only 42 minutes before the sun, compared to the evening crescent setting 48 minutes after the sun.

February 2014 at dusk: The two brightest “stars” at dusk in February are, by a wide margin, steady yellowish Jupiter, high in the east, and blue-white, madly twinkling Sirius, the dog star, in the southeast. The only other evening planet is Mercury, very low south of west, but it will fade and is on its way to conjunction with the sun.

The waxing gibbous moon, four days before full, appears near Jupiter on the evening of Feb. 10.

Surrounding Jupiter is the huge Winter Hexagon of Sirius-Procyon-Pollux-Capella-Aldebaran-Rigel. The noticeably red star Betelgeuse is also within the hexagon. Find the three-star belt of Orion, the hunter, midway between Betelgeuse and bluish Rigel. The belt, extended southeastward, locates Sirius. Extend the belt in the opposite direction, and turn north a bit, and you’ll find Aldebaran, eye of Taurus, the bull. Go farther to find the Pleiades, or seven sisters—a wonderful sight for binoculars! Rising in the eastern sky, Regulus, heart of Leo, is at opposition to the sun on Feb. 18, and chases the Winter Hexagon across the sky.

February 2014 at dawn: This month, Venus attains the peak brilliance of its current morning apparition, which began in mid-January and continues until September. Telescopes and even binoculars reveal Venus now as a crescent, back-lit by the sun. Find Venus before sunrise, and keep track of it—and you can have a daytime sighting! It’ll be especially easy on Feb. 25 and 26, when the crescent moon appears nearby.

For most of February, in morning twilight, you can observe three planets: Venus in the southeast; Saturn in the south; and Mars in the southwest. In the last days of February, a fourth planet appears, once Mercury emerges from its Feb. 15 solar conjunction on near side of sun into the east-southeast twilight glow. Back-lit Mercury is faint at first, but continues to brighten.

Look for these stars within the zodiacal belt: Antares, heart of Scorpius, to the upper right of Venus and lower left of Saturn; Spica near Mars; and Regulus, heart of Leo, in the west far to lower right of Mars and Spica.

In the latter half of February, the waning moon in the morning sky will pass all of these, in west-to-east order: Regulus, Spica, Mars, Saturn, Antares, Venus and Mercury.

Other bright stars at dawn are Arcturus, high above Mars; Spica, in the southwest sky; and the Summer Triangle of Vega-Altair-Deneb, climbing in the eastern sky. The brightest objects visible at morning mid-twilight at start of the month, in order of brilliance, are Venus, Arcturus, Vega and Mars. The red planet nearly doubles in brightness and clearly outshines stars Arcturus and Vega after mid-February.

On Feb. 11, the revolution of spaceship Earth around the sun will be carrying us toward Saturn. A week later, on Feb. 18, Earth passes between the sun and Regulus, and that star appears at opposition—180 degrees from the sun. On Feb. 28, Earth is heading toward a point less than 5 degrees above Antares.

Looking ahead, on April 8, Mars takes its turn at opposition as our planet passes between that planet and the sun. On May 30-31, three weeks after Saturn appears at opposition, Antares will appear at opposition and be above the horizon nearly all night.


A Note on the Sighting of Opposing Crescent Moons, Dec. 31, 2013 and Jan. 1, 2014: A New Record?

On the very clear morning of Tuesday, Dec. 31, Alexander Seidler and I drove to a high spot in a residential area in the northwest corner of Palm Springs. From that site, we had an excellent view of the Coachella Valley below—and spotted the old crescent moon soon after its rising in the east-southeast shortly before 6 a.m. Pacific Standard Time.

We saw it first with 8x42 binoculars, then immediately with unaided eye; we then enjoyed the view through an Orion SkyQuest XT4.5 Dobsonian Reflector at 45x. Alex was able to hold the moon in view with unaided eye until 6:34 a.m., when it was 20 hours and 40 minutes before new. We remained at the site until sunrise and observed a spectacular green flash.

That day, I examined some topographical maps to help me select a different site to provide us with an unobstructed view of the young moon on the evening of Jan. 1. I picked a site in a residential area on the upper-northern part of Desert Hot Springs with a clear view toward Banning Pass in the west-southwest. I visited the site on the evening of Dec. 31 to make timed observations of Venus. Doing so helped me predict, within narrow limits, where the very thin young moon would appear at earlier stages of twilight on Jan. 1.

We returned to the Desert Hot Springs site with two others on Jan. 1, equipped with two pairs of 8x42 binoculars, a pair of 15x70’s, and two Orion SkyQuest 4.5-inch Dobsonian reflectors: one at 36x and the other at 45x. As we looked through some thin streaks of cirrus cloud, Alex was the first to spot the extremely thin crescent, through the 4.5-inch at 36x, at 5:11 p.m. PST, when its age was 13 hours, 57 minutes.

Another observer in our party of four, Andrew Smith, spotted it through the same scope within a few minutes, and I finally caught a brief glimpse using the other telescope at 45x.

A fourth member of our evening party, Misti Rausch, never did see the moon that evening. It may have been because she lost her eyeglasses and had difficulty adjusting the telescope to the appropriate focus. When I tried to refocus my telescope with my eyeglasses on immediately after I saw the crescent to enable others to have a look, I was unable to see the moon and never did recover it. None of us observed the moon with the binoculars or with unaided eye that evening.

The time interval between Alex's last observation of the waning moon on Dec. 31 and his first observation of the waxing moon on Jan. 1 was 34 hours and 37 minutes. As far as I know, this may be a new record for the shortest time interval between sightings of opposing crescents. Stephen J. O’Meara spotted opposing crescents 35.7 hours apart exactly 19 years earlier, on Dec. 31 and Jan. 1, 1994-1995 (see his account in the May 1995 issue of Sky and Telescope, Page 105), but he was observing from the big island of Hawaii, where winter days are longer than in Southern California—so it would not have been possible for him to see the opposing Moons as close together in time as we did.

We are eagerly awaiting our next opportunity to see opposing moons on consecutive days, on Feb. 28 and March 1. At civil twilight here in the Coachella Valley, the crescent at dawn on Feb. 28 and at dusk on March 1 will both be just over 18 hours from the new moon, which happens to occur at 12 a.m. on March 1.

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. Robert D. Miller, who provided the twilight 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.

At the turn of every year—the night of Dec. 31-Jan. 1—Sirius the Dog Star, the brightest of nighttime stars (but not as bright as Venus or Jupiter), follows the sun across the sky by almost exactly 12 hours. This means that the blue-white twinkling star reaches its high point in the south on Dec. 31 near local midnight, solar time.

Sirius attains its high point in the south about four minutes earlier each night, or two hours earlier with each passing month. By the start of spring (March 20), Sirius will stand high in the south in evening mid-twilight, only 40 minutes after sunset. In the meantime, enjoy Sirius and the attendant stars of Canis Major, the Greater Dog, marching across the southern sky, acting out the lines of Robert Frost’s poem, “Canis Major”:

The great Overdog

That heavenly beast

With a star in one eye

Gives a leap in the east.

He dances upright

All the way to the west

And never once drops

On his forefeet to rest.

I'm a poor underdog,

But to-night I will bark

With the great Overdog

That romps through the dark.

The moon passes all five bright planets this month, including Venus twice. In the evening sky, within 30 minutes after sunset on Jan. 2, look for soon-to-depart Venus to the lower right of a thin crescent moon low in the southwest to west-southwest. (You’ll need a vantage point without high mountains blocking the view!) A nearly full moon will keep company with Jupiter from dusk until first light of dawn on the night of Jan. 14-15. An hour before sun-up on the mornings of Jan. 22 and 23, watch the waning gibbous moon leapfrog past Spica and the brighter reddish planet Mars just above Spica, well up in the south-southwest. The moon is very closely left of Spica on the morning of Jan. 23, and appears at last quarter phase (half full) on the morning of Jan. 24; on the next morning, the fat crescent appears just below Saturn. Venus, by then a prominent morning “star” low in the east-southeast, will appear to lower left of the waning crescent moon an hour before sunrise on Jan. 29. The next morning, look for the last thin old moon rising to lower left of Venus. Back in the evening sky on Jan. 31, the thin young crescent moon will appear low in the west-southwest at dusk, a few degrees to lower right of Mercury, which pays a brief visit to evening twilight skies in late January and early February.

Venus switches from the evening to the morning sky (with an overlap of a few days), and Jupiter is visible all night early in January. Use binoculars in twilight to reveal Jupiter as a disk, and, all this month, an even larger (in apparent diameter) Venus in a crescent phase. On Jan. 1, Venus is 15 degrees to the upper left of the setting sun. As Venus traverses the near side of its orbit, it will pass only 5 degrees north of the sun on Jan. 10-11. By Jan. 31, Venus will be 29 degrees to the top of the rising sun.

This month, Venus and Jupiter will play hide and seek. The two planets appear in nearly opposite directions in the sky, because Earth overtakes Jupiter on Jan. 5 (creating an opposition of Jupiter, when the giant planet rises at sunset and sets at sunrise), and Venus overtakes Earth on Jan. 11 (creating an inferior conjunction of Venus, when Venus rises and sets nearly together with the sun).

After Venus emerges into the morning sky, see four planets, in east to west order: Venus rising in the east-southeast, Saturn in the south-southeast, Mars in the south-southwest, and Jupiter setting in the west-northwest. Because of our surrounding mountains, you probably won’t spot Venus until after Jupiter has set.

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. Robert D. Miller, who provided the twilight 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.

There are chances on consecutive days to catch a crescent moon within 24 hours of a new moon—a rare thing indeed. Here are the details.

First, look about 45 minutes before sunrise on Tuesday, Dec. 31, to catch the old crescent moon very low in the east-southeast. Binoculars will help you spot the rising moon about 20 degrees to the lower left of Antares. Once you spot the lunar crescent, note the time, and calculate the interval remaining until the new moon, which occurs Jan. 1 at 3:14 a.m. PST. From Southern California, crescent sightings will occur 21 hours before new.

The next chance to see the moon occurs at dusk on Wednesday, Jan. 1. As noted above, the new moon occurs early that day. Using binoculars, start looking for the thin young crescent moon, very low in the west-southwest, about 25 minutes after sunset. You’ll need to observe from a place with an unobstructed view of the brightest part of the twilight sky, directly above the recently set sun. From Southern California, the moon will appear within 8 degrees to the lower right of Venus. If you spot the moon, take note: Only a few observers have succeeded in seeing the moon so close to new.

If you see the easier old moon at dawn on Dec. 31, and also see the very challenging young moon at dusk on Jan. 1, then you’ll have seen opposing crescents on consecutive days, which is really special. Be sure to let us know about it! Include your location, times and details of your observations in an email to This email address is being protected from spambots. You need JavaScript enabled to view it.. And if you know anyone in Hawaii, pass the word: Sky-watchers there will have an easier time getting a Jan. 1 sighting, so it will be easier for them to catch the old crescent at dawn on one day, and the young crescent at dusk on the next.

December’s evening views begin with Venus near its brightest and highest in the southwest; the Summer Triangle of Vega-Altair-Deneb high in the west; and Fomalhaut, mouth of the Southern Fish, just east of due south.

At the start of December, the only bright objects in the eastern sky at mid-twilight are Capella, the mother goat star, in the northeast, and Aldebaran, eye of Taurus, very low in the east-northeast. Around Dec. 1 each year, that star is up all night from dusk to dawn. Wait a few minutes to allow the evening sky to darken a bit, and you’ll notice the compact Pleiades, or Seven Sisters cluster, 14 degrees above Aldebaran. The scene is beautifully described in Alfred Lord Tennyson’s “Locksley Hall”: “Many a night I saw the Pleiades / rising thro’ the mellow shade / glittering like a swarm of fireflies / tangled in a silver braid.” Don’t miss the view of the Pleiades through binoculars!

By month’s end, Venus is much lower in the west-southwest, because it’s heading toward inferior conjunction, nearly between Earth and the sun, on Jan. 11. The Summer Triangle is lower, too, and Fomalhaut crosses west of south, both owing to Earth’s revolution around the sun. Capella and Aldebaran rise higher in December for the same reason. Betelgeuse and Rigel, Orion’s brighter shoulder and foot, appear above the eastern horizon four minutes earlier each evening during twilight as the year’s end draws near. Between them, note the vertical line of three stars—Orion’s belt! Poet Robert Frost in “The Star-Splitter” (about a farmer who set fire to his house to collect insurance money to buy a telescope) describes what you can observe here in the Coachella Valley at this time of year: “You know Orion always comes up sideways / throwing a leg up over our fence of mountains …”

In the final days of December, bright Jupiter appears above our evening twilight horizon. From a good vantage point, you can spot Venus and Jupiter simultaneously. As Venus approaches the horizon, watch for Jupiter to rise in the opposite direction. Of course, you can spot Jupiter on any date this month just by looking late enough in the evening.

Don’t miss Venus near the crescent moon early on Thursday evening, Dec. 5. It’s also a great chance to spot Venus in the daytime, all afternoon! Here are times for each Sunday when Venus is directly south, with its height above the horizon in degrees, as seen from the Coachella Valley: Dec. 1, 2:40 p.m., 32 degrees up; Dec. 8, 2:28 p.m., 33 degrees up; Dec. 15, 2:10 p.m., 34 degrees up; Dec. 22, 1:44 p.m., 36 degrees up; and Dec. 29, 1:09 p.m., 38 degrees up. Many roads in the valley run north-south, which will help you face the right direction. Aim your binoculars at a distant mountain, and focus. Then point toward Venus, and observe its current crescent phase, getting thinner and larger in size as this month progresses! (Take care that you do not aim binoculars at the sun.)

Our morning twilight map (below) shows the sky nearly 45 minutes before sunup. On Sunday, Dec. 1, five solar-system bodies are easily visible. From west to east, they are Jupiter, about halfway from horizon to overhead in west; Mars, even higher in the south-southeast; and a clustering of Saturn, the old crescent moon, and Mercury low in the east-southeast. From the Coachella Valley, Saturn is 4 degrees above the thin moon, and Mercury appears within 4 degrees to the moon’s lower left. There are less than 35 hours until the invisible new moon (on Dec. 2 at 4:22 p.m.), so the moon will be gone by Monday morning. Mercury drops out of sight in December’s second week, on its way to the far side of the sun on Dec. 28.

The two brightest objects in our morning sky are steady Jupiter, sinking west toward west-northwest, and twinkling Sirius, until it sets in the west-southwest.

On Dec. 1, Earth is heading in the direction of 10 degrees east (left) of Regulus. As the Earth curves around the sun in the next five months, it will overtake the slower-moving outer planets: Jupiter in early January, Mars in early April, and Saturn before the middle of May. As a result, these planets, along with their background stars, will progress toward the western horizon in our morning sky, and will appear above our eastern horizon in the early evening sky as Earth passes them in turn.

On Dec. 2, Mars appears midway between Regulus and Spica, 27 degrees from each.

If you enjoy chasing very thin crescent moons in twilight, there’ll be three chances in coming weeks: (1) A young crescent on the evening of Tuesday, Dec. 3, age 25 hours, very low in west-southwest 28 degrees to the lower right of Venus; (2) a very old crescent on the morning of Dec. 31, 21 hours before new, very low in the east-southwest, 20 degrees to the lower left of Antares; and (3) an extremely young crescent in the very early evening on Jan. 1, age 14 hours, within 8 degrees to the lower right of Venus. (My personal record for a youngest moon sighting is 13.5 hours past new.)

The Geminid meteor shower is largely spoiled by bright moonlight this year. The best viewing with the least moonlight will occur on Friday, Dec. 13 from 3:30 to 5:30 a.m., and on Saturday, Dec. 14, from 4:30 to 5:30 a.m.

Comet ISON will pass within 725,000 miles of the sun’s surface on Thanksgiving Day and make a sharp turn to the north, or upper left, of the predawn sun. By Dec. 6, it will rise as morning twilight begins. Visit www.pa.msu.edu/abrams/ison/ for updates on the comet.

The Astronomical Society of the Desert will host a skywatching session on Saturday, Dec. 7, from 5 to 8 p.m. 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 on the club’s activities, visit astrorx.org. The Whitewater Preserve is hosting a skywatch on Friday, Dec. 20, from 5:30 to 9 p.m., preceded by afternoon viewing of the crescent Venus. I hope to see you there, and at some of the WildLights evenings at the Living Desert, where we’ll show the crescent Venus and other sky phenomena.

Robert C. Victor was a staff astronomer at Abrams Planetarium, 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, 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.

A common yet striking event is the monthly pairing of Venus and the crescent moon. In the closing 10 weeks of Venus’ current evening apparition, pairings will occur at dusk on Nov. 6, Dec. 5, and Jan. 1 and 2.

Jupiter is usually the planet next in terms of brilliance after Venus, so its pairings near the moon, occurring at intervals of 27 to 28 days, are often impressive. The moon is always in its crescent phase when it is seen near Venus, but can appear in any phase, from a thin crescent to full, when it passes Jupiter. This month, Jupiter will appear near the moon on the night of Nov. 21-22, from four hours after sunset until dawn.

Venus appears at greatest elongation, appearing a maximum of 47 degrees from the sun in our sky on Oct. 31, in the afternoon and evening sky, and on March 22, 2014, in the morning. Through a telescope near those dates, Venus appears as a tiny “half moon.” The 20 weeks from the end of October to late March will be an exciting time to follow Venus through telescopes and binoculars, as the backlit planet swings close to Earth and displays all its crescent phases—in the daytime as well as at dusk or dawn.

On our evening twilight chart for November 2013 (above), bright objects are plotted for each day when the sun has sunk to 9 degrees below the horizon, at “mid-twilight.” By then, Venus and about a half-dozen stars of first magnitude or brighter, including the summer triangle of Vega, Altair and Deneb high in the western sky, are easily seen. In November, mid-twilight in the Coachella Valley occurs about 40 to 43 minutes after sunset. Planet positions are represented by a separate dot for each date, with positions for each Friday in November (1, 8, 15, 22, 29) represented by a larger dot and labeled. Rotate the chart until the portion of the horizon circle nearest to your target objects is below them, and you’ll see them depicted at the same orientation as they appear in the sky.

Jupiter does not appear on the evening twilight chart. On Nov. 1, it rises within 4 1/2 hours after sunset. Its rising time shifts earlier by about four minutes per day, until at month’s end, it will rise a few minutes before Venus sets.

Jupiter is also present in the morning, as the brightest “star” then visible. In mid-twilight (see the map below), find it very high in the southwest on Nov. 1, moving about halfway from horizon to overhead in west at month’s end. The other morning planet in view for entire month is Mars. In November, find the red planet just over halfway up, drifting through the southeast early in the month, ending in the south-southeast.

Two additional planets join the morning scene as they emerge from the sun’s glare. The November chart depicting the sky in morning mid-twilight illustrates the changing positions of the four morning planets. First, Mercury pulls out from its Nov. 1 inferior conjunction on the near side of the sun to be spotted by Nov. 8. Look low in the east-southeast, to the lower left of Spica. Mercury brightens, rapidly at first, and then more slowly. Next, just after midmonth, Saturn emerges from the far side of the sun to appear to the lower left of Mercury. The two planets form a close pair on Nov. 25 and 26 and switch places as speedy Mercury moves around toward the far side of its orbit. Saturn appears higher each morning because of the Earth’s faster orbital motion.

On Thanksgiving morning, Nov. 28, four planets—Mercury, Saturn, Mars and Jupiter—span 120 degrees across the sky. Later that same day, Comet ISON will pass within 725,000 miles of the sun’s surface and make a sharp turn to the north, or upper left of the predawn sun. Visit www.pa.msu.edu/abrams/ison for updates on the comet.

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. Robert D. Miller, who provided the twilight 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.