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Last updateMon, 24 Aug 2020 12pm

Robert Victor

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.

March 2015 at dusk: Early in the month, the four brightest “stars,” in order of brilliance, are: Venus, in the west; Jupiter, in the eastern sky; Sirius, the “Dog Star,” 40 degrees up in the south as seen from the Coachella Valley; and Canopus, less than 4 degrees up when it passes due south about 21 minutes before Sirius does.

From the Coachella Valley, you must choose your site carefully to see Canopus, or mountains might block your view. From my abode in Palm Springs, I see Canopus blink out when it goes behind a mountainside several minutes before it reaches its high point.

From Palm Springs and Desert Hot Springs, Canopus passes due south only 4 degrees up in a dark sky at 7:32 p.m. on March 1, and then four minutes earlier each day, to 7:08 p.m. on March 7, and suddenly 8:04 p.m. on Sunday, March 8—an hour later than you might expect, until you recall that you’ve just reset your clock to daylight saving time. By March 11 or 12, the star reaches its high point only about an hour after sunset. Within a few more days, as the star’s “transit time” backs closer to the time of sunset, the sky will become too bright to catch Canopus at its high point.

Sounds of nature enrich the stargazing experience. In Palm Springs, we’ve been hearing frogs in nearby Tahquitz Creek on warmer nights since December.

Other features of the early evening: A telescope reveals Venus now in gibbous phase,and up to four of Jupiter’s moons discovered by Galileo in 1610. Mars, now on the far side of its orbit, doesn’t reveal much telescopically, but it’s visible to the naked eye and binoculars, sinking lower in twilight, 4 degrees to 17 degrees below Venus.

Orion’s three-star belt (not bright enough to be shown on our twilight chart) lies midway between red Betelgeuse and blue Rigel. The belt points the way leftward toward Sirius, and the opposite way toward Aldebaran, eye of Taurus, the Bull, and beyond to the Pleiades or “Seven Sisters” star cluster (also not plotted, but beautiful in binoculars). The huge “Winter Hexagon”—in counterclockwise order, Sirius, Rigel, Aldebaran, Capella, Pollux, Castor (not shown), Procyon and back to Sirius, with Betelgeuse inside—contains seven of the 21 stellar objects of first magnitude or brighter (16 stars and five planets) ever visible from Southern California. 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 on his shoulder.

Following this menagerie is bright Jupiter, itself followed by Leo, the Lion, with the star Regulus marking his heart.

By March’s end, Arcturus, the “Bear Guardian” star, pops up above the east-northeast horizon before mid-twilight. Use this memory aid: “Follow the arc (curve of the bear’s tail or handle of the Big Dipper) to Arcturus.”

The moon can be easily spotted daily at evening mid-twilight (about 40 minutes after sunset) March 1-5 and March 21-April 4. At dusk on Monday, March 2, the fat gibbous moon is well up in the eastern sky, 5 to 6 degrees to the north (upper left) of Jupiter. Now through July, the moon will pass Jupiter in the evening sky every 27 or 28 days. The interval is shorter than the moon’s cycle of phases, 29.5 days, so each time it overtakes Jupiter, the moon will appear progressively less full.

On March 4, the nearly full moon will rise 35 to 40 minutes before sunset, and on March 5, the moon, just past full, rises shortly after sunset. In the following days, moonrise occurs nearly an hour later each night, making it more convenient to switch your moon-watching time to predawn.

March 2015 at dawn: The brightest objects in morning twilight, in order of brilliance, are: Arcturus, high in the west-southwest to west; and Vega, high in the northeast. Early in the month, Mercury, low in the east-southeast, closely matches or slightly outshines Arcturus, but it sinks into bright twilight after midmonth. Saturn, steady in the south to southwest, is next in brightness in the morning sky.

In morning twilight on Thursday, March 5, the full moon is low in the west, with Regulus setting 4 to 5 degrees to its lower right. On March 8 and 9, the waning gibbous moon appears in the southwest near Spica. On Thursday, March 12, Saturn appears within 3 degrees to the lower right of the moon in the south, while the reddish twinkling star Antares appears 8 to 9 degrees to their lower left. On Friday, March 13, the moon is close to half full and essentially at last quarter phase, 90 degrees west of the sun and 14 to 16 degrees left (east) of Antares and Saturn. The last easy morning view of the waning moon will come on Wednesday, March 18.

The moon returns to the evening on Saturday, March 21, at dusk, when the 1.7-day-old waxing crescent will be very easy to spot. Mars will be 2 degrees to its lower right. For a few more evenings, look for beautiful earthshine, from sunlight reflected by 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.

Mark your calendars: On Friday evening, April 3, the nearly full moon will rise 4 to 5 degrees south of due east about 26 minutes before sunset. About 13 minutes before sunset, the sun and moon can be viewed simultaneously, in opposite directions, each about 2 degrees above unobstructed horizons. About an hour after sunset, look for Spica 13 degrees below the moon—and then atotal lunar eclipsewill happen early Saturday morning, April 4. More on this next month and at CVIndependent.com.

Using a rectified Earth globe outdoors in sunlight: If it is set up properly outdoors in sunlight, an Earth globe can reveal the location of the sunlit area on the actual Earth at the moment you are viewing the globe.

Here are directions for setting it up. It would be most helpful if you could use a globe with a dull finish:

1. Find your location. Use longitude and latitude if necessary.

2. Place the globe so that your location is at the top of the globe, i.e., at the highest point on the sphere, at the point of tangency of a horizontal plane tangent to the top of the globe.

3. Rotate the globe about a vertical axis until the directions north, east, south and west at your chosen location on the surface of the globe match the directions of your actual surroundings. During this step, make sure your location remains on the top of the globe.

4. You have now “rectified the globe,” and its orientation in space matches that of the actual Earth. The rotation axis of the globe points very nearly toward the North Star, Polaris, as does the axis of rotation of the actual Earth. Any time you view the globe, its sunlit area matches the sunlight area on the actual Earth.

Examine the globe to discover in what parts of the world the sun is rising, and where it is setting at the time you view the globe. To help solve this problem, watch the globe for several minutes or check it after an hour to detect changes in the location of the lighted area.

On March 20, the date of the spring equinox, the North and South poles should both be on the terminator, or dividing line between the day and night sides of Earth. The sun is directly overhead on the equator. As the Earth rotates on its axis on that date, each location will have days and nights each 12 hours long.

Before March 20, the sunlit area extends beyond the South Pole, and falls short of the North Pole. It is daytime at the South Pole and nighttime (perhaps twilight, depending on the date) at the North Pole. After March 20, the sunlit area falls short of the South Pole, and extends beyond the North Pole, so it is nighttime (perhaps twilight) at the South Pole and daytime at the North Pole.

The “half moon” as a reviewer or predictor of the seasons: The following statement is true throughout the year: the last quarter moon, or half moon at sunrise, reviews the sun’s location of three months ago, and the first quarter moon, or half moon at sunset, predicts the sun’s location three months in the future.

These facts are especially well demonstrated in March: The morning half moon at sunrise on March 13 is low in the southern sky, in Ophiuchus, not far from the southernmost part of the zodiac in Sagittarius where the sun appeared in December, near the start of winter.

The evening half moon at sunset nearly two weeks later on March 26 is high in the southern sky, in the club of Orion, not far from the northernmost part of the zodiac near the Taurus-Gemini boundary where the Sun will appear in June, near the start of summer.

You can construct models of the solar system to explain the above facts. Essentials to include in the model are an Earth rotating about its tilted axis while revolving about the sun, and the moon revolving about the Earth in approximately the same plane. All three motions are counterclockwise as seen from “above” or north of the solar system. Placards with names of the 13 zodiac constellations can also be properly arranged around the model, as on the planet orbit charts available online at www.abramsplanetarium.org/msta.

Observing challenge: Opposing crescents on consecutive days, March 19 and 20: Given perfect skies and no mountains blocking the view, use binoculars or a telescope to try to see a very thin waning crescent moon on Thursday, March 19, 25 minutes before sunrise, 1-2 degrees up and 5 degrees south of due east. From Palm Springs, the moon is then only 20.2 hours before new.

On the next day, Friday, March 20, in the evening 25 minutes after sunset, use binoculars to try for an even thinner, waxing crescent, 2-3 degrees up and 2 degrees north of due west. From Palm Springs, the moon is then 16.8 hours after new.

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.

Two planets and a star far outshine all competitors at dusk in February.

They are: Venus, of magnitude -4, low in the west-southwest, shifting toward the west and slowly gaining altitude as this month progresses; Jupiter, of magnitude -2.6, starting very low in the east-northeast, moving into the east and climbing about 1 degree higher each day (if viewed at the same stage of twilight daily); and blue-white Sirius, the “Dog Star” and brightest of nighttime stars, twinkling at magnitude -1.4 and ascending through southeast toward south-southeast at dusk as February runs its course.

Follow these three bright objects at dusk in coming months. Sirius will disappear into the west-southwest twilight glow during May, while Venus and Jupiter remain in view until at least late in July.

February’s other naked-eye evening planet is Mars, appearing as a red “star” of magnitude +1.2 to +1.3, not far from Venus all this month. Look about 9 degrees to the upper left of the brighter planet on Feb. 1, to 3 degrees to the lower right on Feb. 28. Both planets move rapidly against background stars, and remain within 10 degrees of each other for six weeks, starting on Jan. 31.

Stars at dusk: Look for the huge Winter Hexagon of Sirius-Procyon-Pollux-Capella-Aldebaran-Rigel. The noticeably red star Betelgeuse is within the Hexagon. Find the three-star belt of Orion, the hunter, midway between his shoulder, Betelgeuse, and his foot, bluish Rigel. The belt extended southeastward locates Sirius. Extend the belt in the opposite direction, bending 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!

Moon at dusk in early February: On Feb. 1 at dusk, less than two days before full, the moon appears between Pollux, the brighter of the Gemini twins, and Procyon, the Lesser Dog star. (The moon will return to the same place among the stars in just a little more than 27 days, but at a lesser phase, on the final evening of this month.) On Feb. 3, the moon, just past full and rising a few minutes after sunset, appears 5-6 degrees south (to the right) of bright Jupiter. The moon rises about an hour after sunset on Feb. 4, and nearly an hour later nightly for the next several evenings. Rather than staying up late to watch moonrise, shift your viewing time to morning, and follow our satellite in the morning twilight, less than an hour before sunrise:

Moon in morning twilight:

Feb. 3: Nearly full moon, setting in the west to west-northwest, 10 degrees to the lower right of Jupiter.

Feb. 4: Moon just past full, low, just north of west, 7 degrees to the lower left of Jupiter.

Feb. 5: Moon low in the west, 5-6 degrees to the lower left of Regulus.

Feb. 9: Waning gibbous moon in the southwest, less than 4 degrees to the upper right of Spica.

Feb. 12: Moon just past last quarter phase in south, a little less than half full, 5 degrees to the upper right of Saturn.

Feb. 13: Waning crescent moon in the south-southeast, about 8 degrees left of Saturn and 8-9 degrees to the upper left of Antares.

Feb. 16: Thin crescent moon low in the southeast to east-southeast, 9 degrees to the upper right of Mercury.

Feb. 17: Last old very thin crescent moon very low in the east-southeast, 6 degrees to the lower left of Mercury.

The new moon, invisible near the sun, occurs on Feb. 18 at 3:47 p.m. The moon returns to evening sky on Feb. 19. About 40 minutes after sunset, look for the young, thin crescent about 9 degrees south of due west and 6 degrees up, 13-14 degrees to the lower right of Venus.

Be sure to catch the spectacular gathering of the crescent moon and two planets at dusk on Feb. 20, all within a 2 degree field. The 2-day-old moonwill be within 1.7 degrees to the upper right of Venus, with Mars in between them, 0.7 degrees to the upper right of Venus. Venus-Mars appear closest to each other the next evening, Feb. 21, as Venus passes 0.4 degrees south of Mars. That same evening, the crescent moon will appear 14-15 degrees above the pair; as darkness falls, binoculars will show another planet, sixth-magnitude Uranus, just 2 degrees below and slightly right of the moon.

On Feb. 24, the fat crescent moon passes 8 degrees to the south of the Pleiades, or Seven Sisters star cluster. By the next evening, the moon will have passed first quarter phase and will appear just over half full, within 2 degrees to the east of Aldebaran, eye of Taurus the bull. As we look out the rear window of Spaceship Earth on Feb. 24-28, we are speeding away from the Hyades star cluster with Aldebaran in the foreground. On the night of Feb. 28, the waxing gibbous moon will lie about midway between Pollux and Procyon.

February 2015 at dawn: For most of February, in the morning twilight, you can observe as many as three planets: Jupiter, before it drops below horizon in the west-northwest near end of third week; Saturn, in the south all month; and Mercury, after it brightens to first magnitude early in second week. Look for these bright stars, also within the zodiacal belt, within a few degrees of the plane of Earth’s orbit: Antares, heart of Scorpius, to the lower left of Saturn; Spica to right of Saturn; and Regulus, heart of Leo, in the west, far to lower right Spica and upper left of Jupiter.

Other bright stars at dawn are Arcturus, high above Spica in the southwest sky; and the Summer Triangle of Vega-Altair-Deneb, climbing in the eastern sky. Brightest objects at morning mid-twilight for most of February, in order of brilliance, are: Jupiter (until it drops below the west-northwest horizon), Arcturus, and Vega. In the last week of February, Jupiter sets before middle of morning twilight, but Mercury becomes a close match in brightness to these two stars.

A View out the Front Window of Spaceship Earth!

Step outside on February mornings about an hour before sunrise, and visualize the motion of our planet in orbit around the sun.

In what direction are we heading? The sun is below the eastern horizon, below the brightest twilight glow. If you could go to a place high “above” the solar system, high in the northern sky toward the constellation Draco, and look “down,” you would observe that the revolutions of the eight planets around the sun, as well as the revolution of the moon around the Earth would all be counterclockwise.

On Feb. 6, Earth passes between sun and Jupiter, and that planet appears at opposition, 180 degrees from the sun. Note the star Regulus, 12 degrees to the upper left of Jupiter that morning. Twelve days later, on Feb. 18, Earth passes between Sun and Regulus, and that star takes its turn at opposition. If you look each morning at the same stage of twilight, Jupiter and Regulus appear lower daily, as we overtake and then look back at them.

On Feb. 23, the revolution of Spaceship Earth around the sun is carrying us toward Saturn. By Feb. 28, Earth is heading toward a point 5 degrees north of Antares in the predawn sky (and away from a point 5 degrees north of Aldebaran in the evening sky). As we travel around our curving orbit and overtake Saturn on May 22, that planet will appear at opposition and be above the horizon all night, and on May 31, Antares will be at opposition.

Mercury, an inner planet moving faster than Earth, passed nearly between Earth and Sun, inferior conjunction, on Jan. 30, and then moved ahead of us to emerge into the morning sky in February (faint at first, while displaying a backlighted crescent). Mercury reaches greatest elongation on Feb. 24. Next heading toward the far side of the sun, Mercury will drop below the horizon at morning mid-twilight by mid-March, and finally pass beyond the Sun at superior conjunction on April 9.

Wishing you clear skies to enjoy the ride on Spaceship Earth!

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.