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Last updateMon, 24 Aug 2020 12pm

Venus, the brightest planet, and ruddy Mars dominate September’s predawn mornings. Bright Jupiter and nearby Saturn float in the southern sky at nightfall, while creeping slightly closer together. Mars doubles in brilliance for the second consecutive month—and will outshine Jupiter by late September—while the red planet’s rising time shifts two hours earlier, into evening twilight.

Do you enjoy watching moonrises? During Sept. 1-7, the moon rises no more than 30 minutes later on each successive evening. Notice the moon’s reddened color and flattened shape at each moonrise; the moon’s decreasing phase from one day to the next; and the northward shift of its rising place from day to day, from the full moon’s rise at 7:23 p.m. on Sept. 1, through the 70-percent full moon’s rise at 10:13 p.m. on Sept. 7. Note bright Mars less than a degree above the rising moon on evening of Sept. 5. They’re still 3-4 degrees apart, high in the southwest in the hour before sunrise, on Sunday, Sept. 6.

Another chance to witness a string of evening moonrises will occur Oct. 1-7, beginning with the harvest moon of Oct. 1.

September at dusk: Jupiter is the bright “star” in south-southeast to south, with Saturn 8.3 to 7.4 degrees to its east (left) in the course of the month. Blue-white Vega is nearly overhead, with nearby Altair and Deneb completing the Summer Triangle. Golden Arcturus is still well up in the west, getting lower as the month progresses. Reddish Antares, heart of the Scorpion, is in the south-southwest to southwest. Early in the month, it’s still easy to see Spica very low in the west-southwest. On Sept. 14, can you spot brighter Mercury 10 degrees to the lower right of Spica? Binoculars and an unobstructed view are needed to follow this pair through their approach low in bright twilight, within 0.6 degrees apart on Sept. 21 and 0.8 degrees apart on Sept. 22. Fomalhaut, mouth of the Southern Fish, appears in the southeast by late in month.

Mars rises in the early evening some 10 degrees north of east within a quarter-hour after Jupiter reaches due south in early and mid-September—or at nearly the same time as Jupiter passes south late in month. Mars surpasses Jupiter’s brightness in late September. To compare them fairly, wait until they’re at equal altitudes later in evening, four hours after sunset around Sept. 9, and three hours after sunset around Sept. 30.

September at dawn: In the first days of September, Venus, shining at magnitude -4.3 to -4.1, stands at its highest in the eastern sky for this apparition. Moving just more than a degree per day against background stars, Venus passes within 9 degrees south of Pollux on Sept. 1. On Sept. 5, the “Twin” stars Castor and Pollux form a straight line with Venus, 15 degrees long. Don’t miss the close pairings of Venus and Regulus on Oct. 2 (0.5 degrees apart) and Oct. 3 (0.7 degrees apart). Venus then goes 1.2 degrees per day eastward against the stars. Following Venus and Regulus daily Sept. 28-Oct. 7 an hour before sunrise should be quite engaging, as day-to-day changes will be easy to notice. With daylight saving time still in effect, sunrise isn’t unreasonably early, so predawn sky watching can be done with little disruption.

Mars, doubling in brilliance from magnitude -1.8 to -2.5 in September, now clearly outshines the brightest star, Sirius. Find the red planet in the southwest to west at dawn, getting lower as month progresses. Bright stars: The entire Winter Hexagon is now in fine view. Begin with its brightest member, Sirius, the Dog Star, in the southeast to south-southeast. Then, in clockwise order, find Procyon, Pollux and Castor, Capella nearly overhead, Aldebaran, Rigel and back to Sirius. Orion’s shoulder, Betelgeuse, is inside the hexagon. It forms the nearly equilateral Winter Triangle with the big and little dog stars, Sirius and Procyon. By the end of the first week of September, Regulus, heart of Leo, emerges low, north of east, and climbs higher daily in the morning twilight glow. By Sept. 30, Venus pulls within 3 degrees to the upper right of Regulus. Deneb, last star of the Summer Triangle to set, is departing in the north-northwest.

Follow the moon, waning from full to a thin crescent, on mornings of Sept. 2-16. Look about one hour before sunrise to catch the moon about 3 degrees to the upper left of Mars on Sept. 6; near Aldebaran, eye of Taurus, on Sept. 9; near Twins Pollux and Castor on Sept. 12 and 13; about 6 degrees to the lower left of Venus on Sept. 14; and near Regulus on Sept. 15. On Sept. 16, look 45 minutes before sunrise to catch the last old crescent moon, 3 degrees up and 12 degrees north of east.

Follow the moon, waxing from thin crescent to full, on the evenings of Sept. 18-Oct. 1. On Sept. 18, look 40 minutes after sunset to catch the thin 4 percent crescent, very low in the west to west-southwest. With binoculars, try for Mercury 5 degrees to the moon’s lower left, and fainter Spica 4.5 degrees to Mercury’s upper left. At the same stage of twilight on Sept. 19, find a thicker 10-percent crescent moon low in the west-southwest, with Mercury 14 degrees to its lower right, and Spica 3 degrees to Mercury’s upper left. For binoculars, Mercury and Spica appear closest to each other, 0.6 degrees apart, very low in bright twilight on Sept. 21. Spica is getting lower each evening (it will be on far side of the sun in middle of next month), while Mercury in this poor apparition edges only marginally higher for another week.

On Sept. 21 and 22, an hour after sunset, look for Antares 8-9 degrees from a fat crescent moon. The moon reaches first quarter phase, half full and 90 degrees east of the sun, on Sept. 23. On Sept. 24, one hour after sunset, Jupiter appears about 3 degrees to the moon’s upper left, with Saturn 7.7 degrees east of Jupiter. Check again some four hours later when they’ve nearly set, and you’ll find Jupiter only about 2 degrees to the upper right of the moon. On Sept. 25, an hour after sunset, the moon will be 4 degrees to the lower left of Saturn and 11 degrees from Jupiter. On Oct. 1, watch for the full moon rising due east within half an hour after sunset. Another half-hour later, watch for Mars rising within 13 degrees to the moon’s lower left.

On night of Oct. 2, shortly after 8 p.m., the moon will be 1 1/4 days past full, and its center will pass only 1.4 degrees south (to the lower right) of Mars. The moon and Mars gradually spread apart for rest of that night, until sunrise on Oct. 3, when you’ll find Mars about 4 degrees to the lower right of the moon. In early October, Mars will present its closest and brightest (magnitude -2.6) approach to Earth until 2035.

The Abrams Planetarium’s monthly Sky Calendar now has more than 3,000 subscribers nationwide. I originated Sky Calendar in October 1968 and produced the October 2020 issue, featuring Mars at its brightest. For more information about Sky Calendar and a sample, visit www.abramsplanetarium.org/skycalendar.

To check for eventual resumption of star parties hosted by the Astronomical Society of the Desert, visit the club’s website at www.astrorx.org.

Wishing you clear skies!

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

Published in Astronomy

August’s planetary scene features giants in tandem in the evening—and four very close pairings of the moon with the three brightest planets. The Perseid meteor shower, somewhat diminished by moonlight this year, peaks in predawn on Aug. 12.

Going camping? The best evenings for viewing the Milky Way from dark sites 90 minutes to three hours after sunset are Aug. 9-21.

Bright Jupiter in the southeast to south-southeast at dusk, and Saturn about 8 degrees to its east, are an attractive pair for evening telescopic observation. Views of Jupiter’s cloud belts and four bright satellites, and Saturn’s spectacular rings, always inspire. Jupiter will be near the moon; on Aug. 1, just before sunset, using binoculars, try to see Jupiter in the daytime, within 3.2 degrees to the upper right of the moon. An hour after sunset, they’re easy to see with the unaided eye, 3.6 degrees apart.

On the next evening, Aug. 2, Saturn and Jupiter appear 9 and 16 degrees to the upper right of the nearly full moon.

In August, Mars rises in the late evening, shortly before or after Jupiter reaches its high point in south. Mars’ tiny disk requires high magnification and steady air to reveal its surface details. I use my 6-inch reflecting telescope at 200-power with Mars high above the horizon, which occurs just before dawn this month. On the night of Aug. 2, Mars passes perihelion, its least amount of distance from sun. And on Sept. 1, the south pole of Mars is tipped its greatest angle toward the sun, initiating the planet’s summer in its southern hemisphere. These events combine to make Mars’ south polar cap, mostly of frozen carbon dioxide, shrink rapidly this month, so look soon for the best views. The south polar cap still appears as a small, bright white oval near the south end of Mars’ mostly rust-colored disk.

Also, the first permanent surface feature noted on Mars, by Christiaan Huygens in 1659, directly faces Earth for several consecutive mornings while Mars is high in our sky. The feature, named Syrtis Major, is an expanse of basaltic volcanic rock appearing as a dark triangle north of the center of the Martian disk. Look about 39 minutes later each day: Aug. 1 at 4:05 a.m.; Aug. 2 at 4:44 a.m.; and Aug. 3 at 5:23 a.m. For resources on observing Mars during 2020, visit www.abramsplanetarium.org/msta.

In the morning sky, Venus rises more than three hours before the sun and is well up in the eastern sky as dawn brightens. Against the star background, Venus shifts 30 degrees in 30 days, Aug. 1-31. On Aug. 2, it passes 1.8 degrees south of third-magnitude Zeta Tauri, tip of the bull’s southern horn. Crossing through northernmost Orion into Gemini, Venus ends August within 9 degrees south of first-magnitude Pollux, Gemini’s brighter twin.

Mercury begins the month 29 degrees to the lower left of Venus and within 7 degrees south of Pollux. Speeding toward superior conjunction on far side of the sun on Aug. 17, Mercury moves 36 degrees to the lower left of Venus by Aug. 8, when binoculars will be useful for spotting it low in bright twilight.

Also on Aug. 8, in morning twilight, find Mars high in the south, 10 degrees to the upper left of the waning gibbous moon, 79 percent full. In the late evening on Aug. 8, as Jupiter reaches due south just before 11 p.m., the moon and Mars will have just risen in the east, with the red planet only 1.7 degrees to the upper left of the 73 percent moon. The moon and Mars will appear closest, 1.4 degrees apart center-to-center, at 1:14 a.m. on Aug. 9. They’re still just 2 degrees apart at sunrise on Aug. 9, with Mars to the lower right of the 70 percent moon.

On the night of Tuesday and Wednesday, August 11-12, the annual Perseid meteor shower reaches its peak. Even before twilight ends on Tuesday evening, shortly after 9 p.m. locally, some “earth-grazing” meteors might be seen. They will be long-lasting, because the meteoroids, leftover particles from previous passages of Comet Swift-Tuttle, will be entering the atmosphere on paths nearly parallel to the horizon. They’ll appear to radiate from the constellation Perseus, then rising in the north-northeast below the familiar “W” of Cassiopeia.

As the night progresses, our part of the Earth’s surface is turned ever more broadside to the incoming meteors, increasing the numbers seen, while the radiant (direction of the source) climbs higher in the northeastern sky. Throughout the darkness hours, meteors might light up anywhere in the sky, but the actual members of the shower, if their tracks are extended backward before the point where they lit up, will intersect at their common radiant, in upper Perseus. (The paths are actually parallel in space, but appear to converge in the distance.) By 11 p.m., Jupiter and Saturn will be 8 degrees apart in the southern sky, and Mars will have risen in the east. Soon after midnight, the count will suffer a setback with the rising of a fat crescent moon—but will increase again for the rest of the night as the radiant continues its ascent. A noted expert on meteor showers predicts that Earth will pass through a dense trail of comet particles around 3 a.m. If so, more meteors than usual will then be seen.

At first light of dawn soon after 4:30 a.m. on Aug. 12, the Pleiades star cluster, beautiful in binoculars, will appear 7 degrees to the upper left of the moon, and red-orange Aldebaran, follower of the Pleiades and eye of Taurus, the Bull, will be 11 degrees to the moon’s lower left. Mars will then be approaching its high point in the south, while Venus will be gleaming in the east. Venus stands at greatest elongation, 46 degrees from the sun, and shows as a “half moon” through a telescope.

On the following morning, Aug. 13, the moon will pass 4 degrees north of Aldebaran. On the 14th, look for Venus 12 degrees to the moon’s lower left; and red Betelgeuse, Orion’s shoulder, 16 degrees to the moon’s lower right. Farther right and a little lower is blue-white Rigel, Orion’s foot. Midway between these colorful stars is the Hunter’s 3-star belt. Follow its line downward to Sirius, the Dog Star, just risen in east-southeast. Close to the east and about the same distance above the horizon, look for Procyon, forming the nearly equilateral Winter Triangle with Sirius and Betelgeuse. If you catch Sirius soon after it rises, turn around to see the entire Summer Triangle of Vega, Deneb and Altair in the northwest to west, before Altair sets, if there’s no mountain blocking your view.

In mid-August, Mars is predicted to equal and then surpass Sirius in brightness, but it’s hard to make a fair comparison now, since Mars is high in the sky while Sirius is low. As Earth closes in until October, Mars nearly doubles its brightness each month in August and September.

Venus near the moon: The waning moon continues eastward through the zodiac toward the sun, and on the morning of Aug. 15, an hour before sunrise, the 16 percent crescent appears within 4 degrees to the north (upper left) of Venus. It’s a pretty sight, with earthshine on the moon’s non-sunlit side! Keep track until sunrise, and you can get a daytime sighting of Venus with the naked-eye or binoculars.

On Aug. 16, the 9-percent crescent moon appears in the east-northeast, 5 to 9 degrees to the lower right of Pollux and Castor, the Gemini twins. The last easy old crescent moon occurs on Aug. 17, as a thin 3 percent sliver, low in the east-northeast, 12 degrees below Pollux.

The invisible new moon occurs as it passes the sun on Aug. 18 at 7:42 p.m. Grab binoculars on the evening of Aug. 19, about 30 minutes after sunset. From a site with an unobstructed view midway between the west and west-northwest, you’ll get a chance to view a young crescent moon, 2 percent full, only 4 degrees up, and just more than 24 hours old.

Follow the waxing moon nightly one hour after sunset, Aug. 20 through Sept. 2. On Aug. 22, the 22 percent crescent moon passes within 6 degrees north of Spica in the west-southwest, in Virgo. On Aug. 25, the 54 percent moon, just past first quarter phase (when it’s half full and 90 degrees east of the sun), passes within 6 degrees to the north of the red supergiant star Antares, heart of the Scorpion.

Jupiter near the moon, reprise: On Aug. 28, just before sunset, use binoculars to try for a daytime sighting of Jupiter, within 2.3 degrees to the upper left of the gibbous moon in the southeast. One hour after sunset, Jupiter will be 2.4 degrees almost directly above the 84 percent moon in the south-southeast. Saturn will be nearly 8 degrees to the left of the moon. That night, Jupiter and Saturn are 8.3 degrees apart, and the gap between them begins to close until their rare and spectacular conjunction just 0.1 degrees apart, at dusk on Dec. 21, 2020.

On Aug. 29, an hour after sunset, find Saturn and Jupiter 6 to 14 degrees to the 91 percent moon’s upper right.

The Abrams Planetarium’s monthly Sky Calendar now has more than 3,000 subscribers nationwide. I originated Sky Calendar in October 1968 and produced the October 2020 issue, featuring Mars at its brightest. For more information about Sky Calendar and a sample, visit www.abramsplanetarium.org/skycalendar.

To check for eventual resumption of star parties hosted by the Astronomical Society of the Desert, visit the club’s website at www.astrorx.org.

Wishing you clear skies!

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

Published in Astronomy

Good news for evening viewers! Jupiter and closely following Saturn are rising about a half-hour earlier per week, so by the dates of their respective oppositions, on the nights of July 14 and 20, they reach peak brilliance and will have just risen at sunset. As darkness descends, the beautiful pair of giant planets will be in the east-southeast, in the deep blue part of the sky, opposite the sun’s direction. After their oppositions, Jupiter and Saturn will remain visible in the evening sky until early in January 2021.

If you enjoy the cool of the morning, then centering your outings 60 to 90 minutes before sunrise will give you many planetary visual treats—including Venus reaching peak brilliance in the east. Starting July 1, Venus slowly moves across the Hyades star cluster until passing just 1 degree north of Aldebaran July 11 and 12. By then, Jupiter and Saturn are nearly at opposition, so they’re getting low in southwest.

Through a telescope—or even through binoculars if you look around sunrise or in the daytime—Venus offers up crescent phases, 19 to 43 percent full this month, but shrinking in apparent size as the planet recedes from Earth. Jupiter, with its cloud belts and four bright Galilean moons, and Saturn, with its amazing rings, are always pleasing. To get a good view of the surface details of Mars requires more magnification: A six-inch reflecting telescope working at 200x has recently shown me excellent views of Mars’ bright south polar cap of frozen carbon dioxide.

A permanent surface feature first noted on Mars by Dutch astronomer Christiaan Huygens in 1659 still can be seen as a dark, roughly triangular patch of basaltic rock now known as Syrtis Major. As Mars rotates on its axis once each 24.65 hours, Syrtis Major will appear just north of the center of the Martian disk, on Tuesday, July 28 at 1:28 a.m., and about 39 minutes later each morning.

If you’re looking an hour before sunrise, and you have unobstructed views, Jupiter and Saturn will remain above your southwestern horizon for several days after their oppositions. Meanwhile, Mars is high in the south-southeast. On July 16 and 17, a waning crescent moon forms beautiful gatherings with Venus, Aldebaran and the Hyades star cluster; on July 18 and 19, the thin old moon appears near Mercury, as the innermost planet brightens low in the east-northeast and emerges from the sun’s glare.

In the evening sky: On July 1, bright Jupiter is just rising in the east-southeast at evening mid-twilight, and Saturn, just more than 6 degrees to its east, rises 20-25 minutes later. The waxing gibbous moon appears near Antares on July 1 and 2. On July 4, watch the full moon rising very close to sunset. After nightfall on July 5, catch the moon between Jupiter and Saturn, below the line joining the two giant planets. Jupiter and Saturn reach opposition as Earth overtakes them; thereafter, for the rest of 2020, they are more favorably placed for evening viewing.

Elsewhere in the sky at dusk in July, watch Antares reach the south, as the Summer Triangle of Vega, Altair and Deneb climbs high in the east. See golden Arcturus and blue-white Spica move through the southwest quadrant, chasing Regulus nearly to the horizon in the west-northwest. The moon returns to the evening sky as a young crescent very low in the west-northwest at dusk on July 21, and appears within 4 degrees above Regulus on July 22. The moon, nearly half full and approaching first-quarter phase, appears near Spica on July 26; in gibbous phase above Antares on July 29; and nearly full, between and below Jupiter and Saturn, on Aug. 1.

July’s morning sky: On July 1, one hour before sunrise, bright Jupiter is in the southwest, with Saturn 6.1 degrees to its upper left. Mars is high in the southeast. Brilliant Venus is in the east-northeast to east, with the reddish first-magnitude Aldebaran, eye of Taurus, 3.4 degrees to its lower left. Views of Venus moving through the Hyades star cluster toward Aldebaran, all in one field of view of binoculars July 1-12, will be spectacular.

From July 5-19, before sunrise, the moon will pass all other seven planets of our solar system. Mercury doesn’t show up until almost the end of that period, and then becomes more prominent after the moon has passed from the scene.

On July 4, an hour before sunrise, the moon is about to set in the southwest to west-southwest. Jupiter is 20 degrees to its upper left, with Saturn 6.2 degrees to the upper left of Jupiter.

On July 5, the full moon is in the southwest, with Jupiter 7 degrees to its upper left, and Saturn 6.3 degrees to the upper left of Jupiter.

On July 8, Aldebaran is within 2 degrees to the lower left of Venus. Watch Venus shift about a half-degree daily the next few mornings, providing spectacular viewing for binoculars.

On July 11, one hour before sunrise, the 64 percent waning gibbous moon is high in the south-southeast, with Mars 5 degrees to its upper left. This morning and tomorrow, Venus appears just 1 degree north of Aldebaran. This is the third and final event of a triple conjunction between the two bodies. The first was visible on the evening of April 14; the second occurred on June 12. This third pairing is well seen, rising in a dark sky some 2 1/2 hours before sunup.

July 12: Find Mars 7 degrees to the upper right of the 55 percent moon, approaching last-quarter phase.

July 14: Jupiter is at opposition, as Earth passes between our solar system’s largest planet and the sun.

July 16: Many spectacular sights this morning! Get outside at least 75 minutes before sunrise, and begin with the 19 percent crescent moon in the east. Brilliant Venus is within 9 degrees to its lower left, with Aldebaran 2.7 degrees to the upper right of Venus, and 6-7 degrees to the lower left of the moon. Binoculars will show stars of the Hyades star cluster between the moon and Aldebaran, and the Pleiades (Seven Sisters) cluster within 8 degrees to the moon’s upper left. Jupiter and Saturn are within 7 degrees, low in the southwest. Mars is high in the south-southeast.

July 17: The 12 percent waning crescent moon is a little north of east an hour before sunrise, in spectacular conjunction with Venus, just 4 degrees to its upper right. It’s not Venus that’s causing the dark, non-sunlit side of the moon to be visible; it’s earthshine! Aldebaran is 3.3 degrees to the upper right of Venus. Using binoculars, look very low in east-northeast 20 degrees to the lower left of moon for Mercury. It’s of magnitude +1.1 and may be difficult to see low in the twilight. By July 21, Mercury brightens to magnitude +0.4 while staying 23 degrees to the lower left of Venus, their least separation for this apparition. Also on July 17, an hour before sunrise, find Mars high in the south-southeast, and Jupiter and Saturn 7 degrees apart low in the southwest to west-southwest.

July 18, an hour before sunrise, see the moon and all five bright planets! The 6 percent crescent moon with earthshine on its dark side is low in the east-northeast. Look 8 degrees to its lower left for Mercury, of magnitude +0.9. Binoculars may still be needed. Venus gleams 16 degrees to the moon’s upper right, with red Aldebaran 4 degrees to the upper right of Venus. Another 4 degrees to the upper right of Aldebaran is the point of the V-shaped Hyades star cluster. Mars is high in the south-southeast. Jupiter is low in the southwest to west-southwest, with Saturn just 7 degrees to its upper left.

If you get out earlier, before the start of twilight, 1 hour 40 minutes before sunrise, with binoculars and good finder charts, you’ll be able to spot Uranus and Neptune.

July 19: It’s the last morning to catch the old moon! If you have a good low horizon toward east-northeast, look for the 2 percent lunar crescent, just risen, 28 degrees to the lower left of Venus. Look for Mercury, magnitude +0.7, 23 degrees to the lower left of Venus, and nearly 6 degrees to the upper right of the moon.

July 20: The five bright planets can be viewed simultaneously. Locally, Mercury (magnitude +0.5) and Jupiter (magnitude -2.7) are 5 degrees above opposite horizons about 55 minutes before sunrise this morning, so you’ll need to seek out a place with unobstructed views if you’re to see five planets at once. Jupiter is very low in the west-southwest, while Saturn (magnitude +0.1), at opposition to the sun, is 7 degrees to the upper left of Jupiter. Mars (magnitude -0.9) is high in the south-southeast. Venus gleams at magnitude -4.6 in the eastern sky, and Mercury is very low in the east-northeast, 23 degrees to the lower left of Venus.

For the next week, Mercury brightens by about 0.1 magnitude daily, and the viewing time to find Mercury and Jupiter at equal altitudes shifts about 2-3 minutes earlier daily. Mercury reaches greatest elongation, 20 degrees from the sun, on July 22, and reaches its greatest elevation in our local morning twilight skies July 24-26, brightening through magnitude 0 on July 23-24, through magnitude 01 on Aug. 2-3.

The Abrams Planetarium monthly Sky Calendar now has over 3,000 subscribers nationwide. For more information, visit www.abramsplanetarium.org/skycalendar.

The next star party hosted by the Astronomical Society of the Desert, tentatively scheduled for July 18 at Saw Mill Trailhead, might be cancelled to prevent the spread of COVID-19; visit the club’s website at www.astrorx.org.

Wishing you clear skies!

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

Published in Astronomy

Midday on June 20 (12:48 p.m. in Palm Springs), the sun passes only 10 degrees south of overhead in the Coachella Valley. Summer officially begins at 2:44 p.m., when the sun is exactly over the Tropic of Cancer, east-northeast of Hawaii.

My advice: Avoid the intense light and heat of midday! Get out during the cool predawn, mostly between 90 minutes and one hour before sunrise, to enjoy the lineup of three or four naked-eye planets.

On mornings in June, Jupiter and Saturn will catch your eye, because they’re only 5-6 degrees apart, drifting across the sky from the south to southwest—Jupiter is the brighter, westernmost member of the pair—while moving little among the stars near the border of Sagittarius and Capricornus. Mars moves from Aquarius into Pisces in June, yet strangely stays fixed in the southeast those 30 mornings, while the zodiac background seems to scroll westward behind the brightening red planet.

Venus adds impressive brilliance to the predawn planetary panorama by mid-June. In Taurus, it hangs in the east-northeast, 9 degrees below the Pleiades star cluster for two weeks, June 14-27, as both rise a few minutes earlier each morning, into a darker predawn sky. Starting on July 1, Venus slowly moves across the Hyades star cluster until passing just one degree north of Aldebaran, eye of the Bull, on July 11 and 12. By then, Jupiter and Saturn will be nearly at opposition, so they’ll be getting low in southwest, almost 180 degrees from the sun.

Mars, brightening from magnitude 0.0 to -0.5, is in the southeast, 41 to 61 degrees east of Saturn. On June 5, Mars lies directly ahead of Spaceship Earth in our pursuit of the red planet, and later in the month displays its minimum gibbous phase, 84 percent full. (When we overtake Mars on Oct. 13, it will appear at opposition and be visible all night.)

Welcome Venus! After passing inferior conjunction, nearly between the Earth and sun, on June 3, Venus climbs quickly into the morning sky, to upper right of the rising sun. By June 13, it’s easy to see with the unaided eye, but very low, at morning mid-twilight. Even a few days before that date, you can use binoculars to pick out Venus’ very thin crescent in a brighter sky. While Venus is less than 15 degrees from the sun before June 13, protect your eyes by blocking the sun with a building, or looking before sunrise. By June 15, Venus rises an hour before the sun, and by June 30, two hours before.

Telescopic views: Enjoy Jupiter, with two dark equatorial cloud belts and four bright satellites discovered by Galileo; Saturn’s rings now tipped 21 degrees from edge-on; and Mars’ frozen carbon dioxide south polar cap, now extensive while it is mid-spring in that hemisphere. Syrtis Major, the largest dark marking on Mars, first seen in 1659, will be well-placed nearest to the center of the planet’s disk on June 23 at 2:52 a.m.; June 24 at 3:32 a.m.; June 25 at 4:12 a.m.; and June 26 at 4:52 a.m. To see these details on Mars more than three months before its closest approach requires high magnification, but Venus’ crescent is easy to see with low power. Watch it thicken from 5 percent on June 15, through 10 percent on June 21, to 15 percent on June 27, and 20 percent on July 2, while shrinking in apparent size as it recedes from Earth.

As for stars, the Summer Triangle of Vega, Altair and Deneb passes overhead, chasing Arcturus and Antares below the western horizon. Fomalhaut, mouth of the Southern Fish, approaches its highest position, in the south.

The waning moon, in gibbous phase, skips past Jupiter and Saturn on the mornings of June 8 and 9. A few days later, the moon—near last-quarter phase and about half illuminated—appears near Mars on June 12 and 13. On the morning of June 18, look for Venus 10-11 degrees to the lower left of an 8 percent crescent moon. On June 19, look for the last, 3 percent old moon, just 2 degrees to the lower left of Venus. It might be too difficult to spot Aldebaran in bright twilight that morning, within 5 degrees to the lower left of Venus and 3 degrees to the lower right of the moon. The moon drops out, but Venus and Aldebaran get higher each morning, spreading to 5.1 degrees apart June 22-25, as Venus ends retrograde in Taurus.

From June 21-24, the four planets Venus, Mars, Saturn and Jupiter span a minimum arc of 130 degrees across the sky. Spectacular for binoculars: On June 30, Venus, entering the Hyades star cluster, will be within 4.5 degrees to the upper right of Aldebaran; and on July 11 and 12, Venus will pass just one degree north of the red, first-magnitude star.

June evenings: Mercury on June 1 is of magnitude +0.2 and near peak altitude for this apparition, low in the west-northwest evening twilight, below the “Gemini Arch” of Procyon, Pollux, Castor and Capella. The innermost planet fades to +1.1 by June 10, when it’s 12 degrees below the sinking Twins, and completes an isosceles triangle with them. Thereafter, Mercury quickly fades, and sinks into bright twilight.

Regulus is high in the west-southwest to west; Spica and Arcturus pass through their highest points in the south; and Antares; past opposition, ascends in the southeast. Altair rises north of east to complete the Summer Triangle with Vega and Deneb farther north, to its upper left.

At the end of June, in the east-southeast, Jupiter rises a bit less than an hour after sunset, and Saturn a bit more than an hour, about 20 minutes apart. You can spot them higher in the southeast later in evening; highest in south near 3 a.m.; or in the southwest as dawn brightens.

Waxing moon in the evening: Catch the gibbous moon near Spica on June 1, and a nearly full moon close to Antares on the night of June 4-5. The moon returns to the evening sky on June 22 as a thin crescent low the west-northwest at dusk, to the lower left of Pollux and Castor. Find a fatter crescent moon near Regulus on June 24 and 25. On Saturday, June 27, the moon nears first-quarter phase, half full and 90 degrees from the sun, and is ideal for showing details through binoculars and telescopes. On the next two evenings, find Spica near the gibbous moon.

The Sky Calendar now has more than 3,000 subscribers nationwide. From its first issue in October 1968, without interruption through August 2012, I designed and co-produced the monthly Sky Calendar for Michigan State University’s Abrams Planetarium. I now do about three year. For more information and a sample, visit www.abramsplanetarium.org/skycalendar.For resources on observing Mars during 2020, visit www.abramsplanetarium.org/msta.

The star parties hosted by the Astronomical Society of the Desert are likely to be cancelled through at least June, to help limit the spread of COVID-19. To check for the eventual resumption of activities, visit the club’s website at www.astrorx.org. The Rancho Mirage Library’s Observatory is currently closed as well; watch www.ranchomiragelibrary.org/observatory.html for updates.

Wishing you clear skies!

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

Published in Astronomy

May features the departure of Venus from the western evening sky just days after its close pairing with Mercury. In the southern predawn sky, Jupiter and Saturn remain in “quasi-conjunction,” within 5 degrees all month, while brightening Mars widens its distance to the lower left of our solar system’s giant planets.

Every spring, in nightly outings during the first hour after sunset, you can enjoy following the seasonal departure of bright stars into the western twilight glow. In order of date, they are Rigel, Aldebaran, the Dog Star Sirius and Betelgeuse, as well as—before the end of May this year—Venus. A close conjunction of departing Venus with emerging Mercury will take place on May 21. By the start of June, of winter’s luminaries, only the spring arch of four bright stars remains: from left to right, Procyon, the “Twins” Pollux and Castor, and Capella.

Using a telescope or binoculars held steady during bright twilight, follow the changing crescent phases of Venus, just after sunset in May, and just before sunrise in June and July.

You can also follow the moon nightly at dusk, as it waxes from a thin crescent in the west to full in the east. Then you can switch to predawn viewing to follow it waning from full in the west to a thin crescent in the east.

Early risers this spring can follow the three bright outer planets in the southeast to southern sky: Bright Jupiter pauses within 5 degrees west of Saturn through early June, while red, brightening Mars pulls away to their east.

Nearly all of the lunar and planetary events mentioned here are illustrated on the Abrams Planetarium Sky Calendar. The issue for May 2020, including evening sky maps, are available free at www.abramsplanetarium.org/skycalendar.

Evenings: Even in ordinary years, the May evening sky undergoes rapid change, with the departure of several bright winter stars. But evenings in May 2020 feature the dramatic departure of Venus—watch it get noticeably lower each night until it disappears into bright twilight in month’s final days—and the fast emergence of Mercury from the far side of the sun, around midmonth.

Venus in the foreground, and Mercury in the background, moving in opposite directions, speed past each other on May 21. That evening, they’re just 1 degree apart, allowing the large, thin crescent Venus and tiny, gibbous Mercury to be viewed in the same low-power telescope field! Be sure to catch the compact gathering of the young crescent moon, Venus and Mercury low in the very early evening twilight on May 23. To spot this moon, which begins the month of Shawwal and ends Ramadan on the Islamic calendar, it’ll be essential to find a place where a mountain or a nearby obstruction won’t block your view toward the west-northwest.

At month’s end, the only bright objects remaining in the low western sky in deepening twilight form the “Arch of Spring” in the west to west-northwest, consisting of, from left to right, Procyon, Pollux, Castor and Capella, with Mercury below. Leo’s brightest star, Regulus, at the end of May is still well up in the west-southwest, to the upper left of the arch. The Big Dipper’s curved handle points the way to Arcturus high in the east-southeast, and Virgo’s brightest star, Spica, well up in the south-southeast: Follow the arc to Arcturus, and drive a spike to Spica. The second member of the Summer Triangle to rise, Deneb, appears very low in the northeast, to the lower left of Vega, its brightest member. Finally, locate the red supergiant star Antares, heart of the Scorpion, low in the southeast at dusk in late May. As Earth passes between Antares and the sun on night of May 30-31, Antares stands at opposition and is visible almost all night: Low in the southeast at dusk, at its highest in the south in middle of night, and low in the southwest at dawn.

The moon at dusk, on its way toward full on the night of May 6, passes near Regulus, heart of Leo the Lion, on May 1; and near Spica on May 5. On its next pass through the early evening sky May 23-June 5, catch the moon as a thin crescent below Mercury and Venus on May 23; as a thickening crescent near Pollux on May 26 and near Regulus on May 28; and at first quarter phase, half full, on May 29.

Venus on May 1 is still near peak brilliance, at magnitude -4.7. Slight optical aid reveals it as a crescent, 24 percent illuminated and 40 arcseconds across, large enough to resolve even through 7x binoculars if observed in daylight or soon after sunset, before there’s too much contrast of the brilliant planet against a darkened sky. At sunset on May 1, Venus is 38 degrees to the upper left of the sun and sets more than three hours later. Beginning retrograde, Venus hovers 1.5 degrees from Beta Tauri May 9-12 in a quasi-conjunction, without moving on past the star. Dramatic changes: By May 16, Venus is 25 degrees to the upper left of the setting sun; sets two hours after the sun; and shows a thinner crescent—10 percent lit and 51 arcseconds across. On May 22, Venus is 18 degrees from the sun; sets 90 minutes after sunset; and shows a crescent just 5 percent lit, 55 arcseconds across. Can you still see Venus on May 28? It’s moved to within 9 degrees of the sun; sets 45 minutes after sunset, and shows a very thin crescent of just over 1 percent, 58 arcseconds across.

Mercury passes superior conjunction behind the sun on May 4, and perihelion only five days later, so it emerges fast and bright into evening sky. Using binoculars, can you spot Mercury on May 9, when it shines at magnitude -1.7 and sets just 30 minutes after sunset? If not, it’ll be easy even for unaided eye a few days later. Capture gibbous Mercury and crescent Venus in same telescope field on May 21.

Morning: The morning twilight chart shows bright Jupiter in the southern sky, and Saturn in quasi-conjunction, within 5 degrees to Jupiter’s east (left) all month. Brightening Mars is in the southeast, 20 to 41 degrees to the lower left of Saturn. Watch the moon pass the three bright outer planets May 12-15. Bright stars are the Summer Triangle of Vega, Altair and Deneb overhead, with Arcturus sinking in the west to west-northwest, Antares sinking in the southwest, and Fomalhaut in the southeast, below Mars.

The moon waxes from full in the west-southwest to a thin crescent in the east-southeast from May 7-20. It appears near Antares on May 8 and 9; near Jupiter and Saturn on May 12; at last quarter phase, half full, on May 14; and near Mars on May 15.

Brightest Jupiter (magnitude -2.3 to -2.6 in eastern Sagittarius) is in the south-southeast to south. Saturn (magnitude +0.6 to +0.4 in western Capricornus) is within 5 degrees to Jupiter’s east all month. They’re in quasi-conjunction, with a minimum separation of 4.7 degrees on May 18. They move little this month against stars, as Saturn commences retrograde on May 11, and Jupiter on May 14. A telescope shows Jupiter’s cloud belts and four Galilean moons, and Saturn’s rings. Mars (+0.4 to 0.0) is in the south-southeast, to the lower left of Saturn, by 20 degrees on May 1, by 30 degrees on May 16, and 40 degrees on May 30. Watch Mars pass 0.9 degrees north of two stars in tail of Capricornus May 1-4, and 2 degrees south of a star in Aquarius on May 30. Through a telescope in May, Mars shows a tiny gibbous disk 7.6 to 9.2 arcseconds across, but it is early spring in the red planet’s southern hemisphere, and the large, bright carbon dioxide south polar cap should be readily seen.

For more on Sagittarius, the Territory of Dogs, and resources for telescopic observation of Mars in 2020, visit the Abrams Planetarium Extra content page, at www.abramsplanetarium.org/msta.

Star parties hosted by the Astronomical Society of the Desert have been canceled through at least the end of May. Watch www.astrorx.org for updates.

Wishing you clear skies!

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. Now retired, he often collaborates with John S. French on the Sky Calendar, and enjoys providing sky-watching opportunities for a variety of groups, mostly in the California desert and in Michigan.

Published in Astronomy

In the western sky at dusk, Venus in April attains its greatest brilliance of this year. Before dawn, the three bright outer planets—Mars, Jupiter and Saturn—are visible in the southeast before dawn.

In the evening: Going eastward against the background stars of Taurus at a decreasing pace, Venus loses altitude late in the month. This occurs as Venus comes around to the near side of its orbit, slowing its progress among the zodiac constellations to less than the sun’s rate of one degree per day. Venus attains peak brilliance in its crescent phase in late April.

Winter’s bright stars have moved into the western sky, most of them poised to depart in May. These include Orion’s red supergiant star Betelgeuse, now recovering from its record fade of January and February. Regulus, heart of Leo, climbs high in the south, and golden Arcturus ascends in the east to east-northeast. To Arcturus’ lower right at dusk, blue-white Spica stands at opposition to the sun on April 13 and is visible almost all night.

Binoculars give stunning nightly views! On April 1, two days before the very close pairing of Venus with third-magnitude Alcyone, or Eta Tauri, the brightest star of the Pleiades, they’re within 1.8 degrees. They’ll be less than 0.3 degrees apart on April 3. Binoculars will certainly come in handy for observing the close conjunction!

Venus will be moving east against background stars by about 0.9 degrees per day, pulling away from the Pleiades. On April 5, Venus and Alcyone are 1.9 degrees apart.

Mornings: The gap between Jupiter and Saturn is 6 degrees on April 6, closing to 5 degrees by April 28. Mars moves rapidly east against background stars, increasing its distance east of Saturn from 1 degree on April 1, to 20 degrees on May 1. Stars on April mornings are in locations similar to where we’ll find them in late August and early September at dusk: The Summer Triangle of Vega, Altair and Deneb is approaching overhead, with Arcturus in the west, Antares in the southwest, and Spica setting in the west-southwest. From April 14-16, the moon visits the three bright outer planets, while the moon goes from 6 degrees west of Jupiter to nearly 5 degrees east of Mars.

Venus-moon conjunction in the evening: At sunset on April 26, find Venus about 7 degrees to the right of the 15-percent crescent moon and a little lower. Venus is itself a crescent, 28 percent full and 37 arcseconds across—large enough to detect its shape with a steadily held pair of binoculars. The most fascinating views of Venus, both in daytime and at dusk, are yet to come, in May.

The star parties and lectures hosted by the Astronomical Society of the Desert have been canceled through at least the end of May, as an action to help prevent the spread of COVID-19. For updates on the resumption of activities, check the club’s website at www.astrorx.org. The Rancho Mirage Library’s Observatory is currently closed as well; watch www.ranchomiragelibrary.org/observatory.html for updates.

In the meantime, schedule your own sky-watching routines! Every spring, in nightly outings during the first hour after sunset—perhaps while walking your dog—you can enjoy following the seasonal departure of bright stars into the western twilight glow. In order of date, they are Rigel, Aldebaran, the Dog Star Sirius, Betelgeuse and, in 2020 before the end of May, Venus. A close conjunction of departing Venus with emerging Mercury will take place on May 21. By the start of June, of winter’s luminaries, only an arch of four bright stars remains: from left to right, Procyon, the “Twins” Pollux and Castor, and Capella.

Using binoculars or a telescope during bright twilight, follow the changing crescent phases of Venus, just after sunset in April and May, and just before sunrise in June and July.

You can also follow the moon nightly at dusk, as it waxes from a thin crescent in the west to full in the east. Then, you can switch to predawn viewing to follow the moon waning from full in the west to a thin crescent in the east.

Early risers in spring 2020 can follow the three bright outer planets in the southeast to southern sky: Bright Jupiter pauses within 5 degrees west of Saturn from late April through early June, while red, brightening Mars pulls away to their east.

Beautiful gatherings of the moon, planets and stars are illustrated In the Abrams Planetarium Sky Calendar. For subscription information and a sample copy, visit www.abramsplanetarium.org/SkyCalendar. The sample is the April 2020 issue, with its evening sky map. Please enjoy and share it with others.

Stay safe! Here’s wishing you clear skies!

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. Now retired, he often collaborates with John S. French on the Sky Calendar, and enjoys providing sky-watching opportunities for a variety of groups, mostly in the California desert and in Michigan.

Published in Astronomy

Man, you know it’s been a crappy week when you’re quoted not once, but twice in national stories about the sudden demise of your industry.

Bleh.

But you know what … screw the negativity. There’s enough of that going around. Let’s focus on the positive elements—or at least the potentially positive elements—of the havoc COVID-19 is wreaking worldwide.

Positives? you may reply. There are positives in all this awfulness?!

While I don’t want to diminish how bad things are for many people—and how truly awful they may get in the weeks ahead—yes, there are some small, tiny, slivers of silver linings here.

For starters:

• The pandemic is finally forcing the state to take immediate, drastic action on the homelessness problem. What if, just maybe, we come out of this having made some progress on the huge issue?

• The worldwide shutdown has already drastically lowered the amount of pollution and greenhouse-gas emissions on the planet. Maybe, just maybe, this is an opportunity?

• The efforts being made to fight the virus and adjust to our shelter-in-place reality may lead to scientific advancements, a decline in individualism, a return to a faith in true experts, and all sorts of other good things. Politico Magazine asked more than 30 brainy folks on how COVID-19 will change the world, and what they came up with was mostly positive.

• On clear nights, we can go outside and enjoy the universe. Yes, we’re allowed to go outside and look up at the heavens, and Independent astronomy columnist Robert Victor has some advice.

“In the southeast, about an hour and 15 minutes before sunrise on clear mornings, you’re sure to notice bright Jupiter with two companions nearby. The rest of March will be excellent for following Mars, as it passes Jupiter and Saturn. (You can really notice the reddish color of Mars, from oxidation of its iron-containing surface material!) From March 20 to 31, all three planets will fit within the field of view of low-power binoculars. After that, next chance to see all three in the same binocular field together won’t be until 2040!”

So … yeah. It’s not ALL bad. While we prepare for more horrible things, let’s all hold on to the hope that better times—truly better times—will follow.

Here are today’s updates … almost all of which are positive in some way or another:

• Around the time I hit send on yesterday’s Daily Digest, Gov. Gavin Newsom announced he was extending the shelter-in-place order—already in place in Palm Springs, but not the rest of the Coachella Valley—to the rest of the state. And therefore the rest of the valley.

• I like this idea: The city of Rancho Mirage is giving some help to the city’s restaurants that stay open and offer delivery and takeout during the shelter-in-place order. 

• In a similar vein, the state is making it easier for those restaurants to sell liquor, too. Key quote: “Bona fide eating places (i.e., restaurants) selling beer, wine, and pre-mixed drinks or cocktails for consumption off the licensed premises may do so when sold in conjunction with meals prepared for pick-up or delivery.” Yes!

• First the feds moved the tax-payment date. Now the tax-filing deadline has been extended three months, too.

Netflix is setting up a $100 million fund to help the people who work on Hollywood productions. Awesome move.

• Computer owners: Your machine can help contribute to the fight against the coronavirus.

• Local drag star Anita Rose is doing online drag shows—and promoting others’ online drag shows, too!

• Late-night star Conan O’Brien—who should have never been fired from The Tonight Show—will resume doing full shows the week after next … using Skype and an iPhone.

• Finally … since I started off with the bad news about the continent’s alternative newspapers, I’ll end with the good: These papers are doing amazing work, even as the future looks dire. My friend Chris Faraone of Dig Boston did a roundup of how we’re covering this shit show.

That’s all for today. Just a heads-up: In order to save my sanity, and make my work better moving forward, we’ll probably take tomorrow off from the Daily Digest. But if we do, never fear: We’ll be back Sunday. Now, I have to go finish the April print edition and send it off to press. I’ll have more details on that later—but above is a sneak peak of the cover. I asked my amazing cover designer, Beth Allen, to find an image that sums up these … interesting times, and even though that was pretty much an impossible ask, I think she pulled it off.

Published in Daily Digest

In the western sky after sunset, Venus in late March attains its highest position at dusk and its longest duration of visibility in a dark sky for 2020.

All three bright outer planets—Mars, Jupiter and Saturn—cluster in the southeast before dawn. Don’t miss their rare, once-in-20-years compact gathering from March 18-31. In mid-March, Mercury reaches its highest position during a poor morning twilight appearance, very low in the east-southeast. Binoculars will help you find the innermost planet well to lower left of the outer-planet threesome.

In the March evening sky, the huge Winter Hexagon of bright stars is in fine view, with Sirius, the brightest star, crossing through the south, and Capella, its second-brightest member, passing north of overhead. In clockwise order, locate Sirius, Procyon, Pollux-Castor, Capella, Aldebaran, Rigel and back to Sirius. Orion’s shoulder—red supergiant and future supernova Betelgeuse, inside the hexagon—is still uncharacteristically faint at this writing (matching the other shoulder star), but is expected to recover some of its brilliance before the Winter Hexagon departs from our view in the west in mid-May. Venus far outshines all these stars, and climbs to its highest point around the date of greatest elongation (maximum angular distance from the sun), on March 24. Telescopes show Venus’ phase, then half full. The crescent moon skips past Venus on March 27 and 28, passing widely south of the planet. Catch the Pleiades star cluster (the Seven Sisters) within 5 degrees of Venus for 11 evenings, March 29-April 8. Binoculars give stunning nightly views!

On April 1, two days before the very close pairing of Venus with third-magnitude Alcyone, or Eta Tauri, the brightest member of the Pleiades, they’re within 1.8 degrees. They’ll be less than 0.3 degrees apart on April 3, when binoculars will certainly be handy for observing the very close conjunction! Venus will be moving east against background stars by about 0.9 degrees per day, pulling away from the Pleiades. On April 5, Venus and Alcyone are 1.9 degrees apart.

In the morning sky, bright Jupiter attracts our attention to the southeast, where the three bright outer planets span 18.5 degrees on March 1, closing to 6.3 degrees at month’s end. Can you spot Mercury in the twilight glow to their lower left? Binoculars help.

Early risers will be well rewarded by the rare morning scenes depicted on the illustration from the March 2020 Sky Calendar below. Be sure to catch the compact gathering of the moon and three planets within a span of 8.3 degrees on March 18, and the same three planets spanning just 7.1 to 6.3 degrees during March 20-31, as Mars, in the foreground, passes from Jupiter toward Saturn. Watch Mars pass within 0.7 degrees of Jupiter on March 20, and 0.9 degrees of Saturn on March 31. Several morning scenes of the threesome, as well as scenes of the moon’s return to evening sky, appear in this excerpt from the March Sky Calendar.

Check the website of the Astronomical Society of the Desert at www.astrorx.org for a schedule of star parties. The primary, more-accessible location for our star parties is the Visitor Center of the Santa Rosa and San Jacinto Mountains National Monument, on Highway 111, within four miles south of Highway 111 in Palm Desert. Our next session there will be on Saturday, March 28, from 7 to 10 p.m. Sawmill Trailhead, our high-altitude site (elevation 4,000 feet), will have a star party starting at dusk on Saturday, March 21. The list of star parties on the society’s website includes maps and directions for both locations. Star parties can be cancelled in poor observing weather.

Also, remember to check the Impromptu Star Parties link on the Astronomical Society’s webpage. I’ll be offering sky watches in Palm Springs at the pedestrian bridge over Tahquitz Creek at North Riverside Drive and Camino Real and at other locations. Some sessions will be held in the daytime or at dusk to observe the changing phases of Venus, and some in the predawn to follow the gathering of the three bright outer planets.

Abrams Planetarium publishes a monthly Sky Calendar with an evening sky map. Subscriptions are $12 per year for three printed issues mailed quarterly. The March 2020 issue of the calendar will feature the rare compact gathering of the three bright outer planets in predawn skies, and Venus ascending to its greatest height in the evening sky.

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. Now retired, he often collaborates with John S. French on the Sky Calendar, and enjoys providing sky-watching opportunities for a variety of groups, mostly in the California desert and in Michigan.

Published in Astronomy

In the western evening sky, Mercury reaches one of its highest positions at dusk for 2020. In the predawn darkness of Feb. 18, the moon covers and uncovers Mars. Meanwhile, all three bright outer planets—bright Jupiter, with Mars to its upper right, and Saturn to its lower left—are gradually coming together in the southeast before dawn, until their rare, once-in-20-years compact gathering in late March!

You won’t fail to notice brilliant Venus well up in the west-southwest to west at dusk. Mercury makes an appearance to its lower right. Mercury shines at magnitude -1 on Feb. 1, fading to magnitude 0 on Feb. 13, and magnitude +1 by Feb. 17; it then dims rapidly and drops into bright twilight within a few days. Mercury lingers 24 degrees from Venus Feb. 4-11. The revolution of the planets around the sun is counterclockwise, as viewed from above the northern side of the solar system. Fast-moving Mercury and Venus are gaining on Earth and coming around from the far side to near side of the sun. This causes Mercury (but not cloud-covered Venus) to fade as the planet displays narrowing crescent phases on the near side of its orbit. Mercury appears at greatest elongation, 18 degrees from the sun, on Feb. 10.

Sirius, the “Dog Star” and brightest of the nighttime stars, twinkles vigorously in the southeast. It is the lowest member of the huge Winter Hexagon of stars of first magnitude or brighter. In clockwise order, they are Sirius, Procyon, Pollux (with fainter twin Castor just 4.5 degrees away), Capella (nearly overhead), Aldebaran, Rigel and back to Sirius. Betelgeuse is normally the brightest star inside the boundaries of the Hexagon, but something has happened to this star! At the time of this writing, Betelgeuse appears barely as bright as Bellatrix, the other shoulder of Orion. Keep an eye on Betelgeuse, comparing it to other stars of known brightness; refer to the resources posted at the end of this article.

Other bright stars in February at dusk include Deneb, the last star of the Summer Triangle to slip away in the northwest, and Regulus, heart of Leo, at opposition to the sun on Feb. 18.

Jupiter is the brightest morning “star,” with Mars to its upper right, and Saturn emerging early in February to Jupiter’s lower left. Ranking next after Jupiter in brightness are golden Arcturus, high in the southwest, and blue-white Vega, high in the east-northeast to east. Look for Spica in the southwest, far below Arcturus; Regulus, sinking in the west to west-northwest; reddish Antares, heart of the Scorpion, in the south; and the stars Altair and Deneb completing the Summer Triangle in the eastern sky. By observing the sky at dawn in February, we can get a “sneak preview” of the stars in the positions we’ll see them in at dusk in July.

For three consecutive mornings, Feb. 18-20, the waning crescent moon appears close to each of the three bright outer planets.In fact, on Feb. 18, before dawn, the moon actually occults (covers) Mars. It’s the bright leading edge of the moon that covers Mars, so an optical aid will be needed. From the Coachella Valley, Mars will disappear behind the leading bright edge of the moon at 3:36 a.m., and reappear at the moon’s unlit side at 4:30 a.m. Note the disappearance occurs very low in the sky, only 5 degrees up as seen from our valley. By the time of reappearance, the moon and Mars will be 14 degrees up the southeast. The next morning, on Feb. 19, the moon will be close to Jupiter, and on Feb. 20, close to Saturn.

As you observe these events before sunrise, imagine you are on the forward side of Spaceship Earth in our orbit around the sun. The sun is below the horizon to your left, while our spaceship is gaining on the three bright outer planets ahead of us. We’ll overtake Jupiter and Saturn within a week of each other in July, as we pass between those giant planets and the sun. They’ll appear at opposition, 180 degrees from the sun, and so when the moon appears near them in July, it will appear full. Not until October will we overtake fast-moving Mars, and see a full moon near the red planet.

There are wide pairings of the crescent moon and Venus on Feb. 26 and 27. You can also look just before sunset for Venus in daylight, 10 degrees to the upper right of the moon on Feb. 26, and 6-7 degrees to the lower right of the moon on Feb. 27.

On Friday, Feb. 7, author and columnist Dennis Mammana will present an astronomy lecture, “From Darkness Comes Light,” at the Portola Community Center, at 45480 Portola Ave., in Palm Desert. Doors open at 6:30 p.m. for refreshments, and the talk begins at 7 p.m.

Check the website of the Astronomical Society of the Desert at www.astrorx.org for more information on the lecture and a schedule of star parties.

The primary, more-accessible location for our star parties is the Visitor Center of the Santa Rosa and San Jacinto Mountains National Monument, on Highway 74, within 4 miles south of Highway 111, in Palm Desert. Our next session there will be on Saturday, Feb. 29, from 6 to 9 p.m.Sawmill Trailhead, our high-altitude site (elevation 4,000 feet), will have a star party starting at dusk on Saturday, Feb. 22.The list of star parties on the society’s website includes maps and directions for both locations. Star parties can be cancelled in poor observing weather.

Also, remember to check the Impromptu Star Parties link on the Astronomical Society’s webpage. I’ll be offering sky watches in Palm Springs at the pedestrian bridge over Tahquitz Creek at North Riverside Drive and Camino Real, and at other locations. Some sessions be held in the daytime or at dusk to observe the changing phases of Venus, and some in the predawn to follow the gathering of the three bright outer planets.

Abrams Planetarium publishes a monthly Sky Calendar with an evening sky map. Subscriptions are $12 per year at www.abramsplanetarium.org/skycalendar for three printed issues mailed quarterly. The March 2020 issue of the calendar will feature the rare compact gathering of the three bright outer planets in predawn skies, and Venus ascending to its greatest height in the evening sky.

Wishing you clear skies!

For more on Betelgeuse:

http://stars.astro.illinois.edu/sow/betelgeuse.html

https://www.nytimes.com/interactive/2020/01/09/science/betelgeuse-supernova-fading.html

https://www.skyandtelescope.com/observing/fainting-betelgeuse/

https://www.aavso.org/sites/default/files/10startutorial-2013.pdf

https://www.aavso.org/aavso-alert-notice-690

https://www.aavso.org/

(Enter “alf ori” into the “Pick a Star” box, then select “Plot a light curve” or “Check recent observations.”)

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. Now retired, he often collaborates with John S. French on the Sky Calendar, and enjoys providing sky watching opportunities for a variety of groups, mostly in the California desert and in Michigan. Robert D. Miller 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.Dr. Jeffrey L. Hunt, a retired planetarium director now living in the Chicago area, has taught astronomy and sky watching to all ages. He studied astronomy education at Abrams Planetarium at Michigan State University. Jeff provided the graphs of planet rising and setting times (below); writes an astronomy blog at jeffreylhunt.wordpress.com; and can be followed on Twitter at @jeff_hunt.

Published in Astronomy

Venus climbs higher above the setting sun week by week, and late in January sets more than three hours after sunset. Mercury, after passing the far side of the sun on Jan. 10, emerges into the west-southwest evening twilight sky to the lower right of Venus by the last week of month.

Mars, very slowly brightening, appears in the southeast morning sky. Jupiter emerges into the southeast morning sky to the lower left of Mars by mid-January, followed by Saturn in early February.

By modeling the solar system on orbit charts, or—here’s a weird party idea—asking friends to act out the motions of the planets, you can see why, when an outer planet such as Mars, Jupiter or Saturn is behind the sun, it is transitioning from the evening sky to the morning sky; and why, when either inner planet, Mercury or Venus, is behind the sun, it is transitioning from morning to evening visibility. Each planet moves at a faster angular speed around the sun than any planet farther out, and the direction of rotation of the Earth on its axis is in the same sense as the revolution of the planets around the sun, i.e., counterclockwise as seen from “above,” or north of the solar system.

Search online for: “Professor Zlata! You’re just in time to be the planet Neptune!” I used to have students do this in my astronomy classes long before I ever saw the cartoon.

On evenings in January 2020, Venus climbs ever higher in a dark sky. As Venus advances 1.2 degrees per day through the zodiac compared to the sun’s 1.0 degrees, watch it pass background stars in Capricornus and Aquarius on Jan. 6-8, Jan. 21-24, and Jan. 27. Mercury emerges to the lower right of Venus in the last week of the month (30 degrees on Jan. 23, to 26 degrees on Jan. 31), and will climb highest in evening twilight around Feb. 10, when it will be 24 degrees from Venus.

In second week of January, the “Twin” stars Castor and Pollux in Gemini are at opposition to the sun and are visible all night: Low in the east-northeast at dusk, high in the south in middle of the night, and low in the west-northwest at dawn.

The moon in the morning sky: On Dec. 27, Jupiter was in conjunction on the far side of the sun, and by mid-January, it will emerge into the southeast morning sky, to the lower left of Mars and Antares. The waning moon appears in January’s morning sky, passing near Regulus on Jan. 13, Spica on Jan. 17, and Mars and Antares on Jan. 20; it appears to the upper right of Jupiter on Jan. 22.

After the new moon on Jan. 24, the moon returns to the evening sky. On Jan. 25, just a half-hour after sunset, you’ll need very clear skies to see the young, very thin crescent moon, about 1 percent full and just 3 or 4 degrees up in the west-southwest. Can you spot Mercury within 3 degrees to the moon’s lower right? Binoculars will give the best view of the delicate crescent moon with Mercury in the same field. Mercury will have just emerged from its Jan. 10 superior conjunction on the far side of the sun, and now starts its best evening appearance of the year. It will get easier to see, as Mercury gets higher and sets later each evening until the second week of February. On Jan. 27 and 28 at dusk, Venus appears 6 or 7 degrees from the lunar crescent.

After Jan. 25, the waxing moon climbs higher nightly. On Jan. 26, the 5 percent crescent appears 13 degrees to the upper left of Mercury and 16 degrees to the lower right of Venus. On Monday, Jan. 27, at dusk, the 9 percent crescent moon appears 6 degrees to the lower left of Venus. That day, find the moon about 30 degrees up in the southwest shortly before sunset, and try to spot Venus in the daytime, by looking 6 degrees to the upper right of the lunar crescent. Use a telescope for a closeup of Venus, which displays a tiny gibbous disk 15 arcseconds (1/240 of a degree) across, and 75 percent illuminated. In the coming months, Venus will be ever more fascinating to watch as it comes around to the near side of its orbit; looms ever larger in apparent size; and becomes backlighted by the sun. By late in March, as Venus stands high in the western sky, 46 degrees from the sun, it will be half illuminated, and by late in April, Venus will reach greatest brilliance, while appearing as a crescent, about one-quarter full.

The year begins with Mars as our only morning planet. On Jan. 1, we find Mars at magnitude +1.6 in the southeast, about 12 degrees to the upper right of brighter first-magnitude Antares (whose name, from Greek, ant + Ares, means rival of or opponent to Mars). The two red objects appear no more than 10 degrees apart Jan. 5-30, and no more than 5 degrees Jan. 16-20. They’re closest, within 4.8 degrees, as Mars passes north of the star on Jan. 18. Enjoy them in the same field of view of binoculars for several mornings! Watch for Jupiter emerging to the lower left of Mars in mid-January, and Saturn to the lower left of Jupiter by early February. Antares wins its ongoing brightness contest with Mars for now, but during March, Mars begins to outshine the star, and there’ll be a rare compact gathering of all three bright outer planets late that month. Earth closes in on the red planet until early October, so watch it brighten until then, to magnitude -2.6, outshining Jupiter!

How often does Mars pass Antares in our sky? If we were located at the sun, the answer would be every 687 days, or about every 22.6 months, the sidereal period of revolution of Mars around the sun. But as seen from our moving Earth, conjunctions of Mars-Antares do not occur at equal intervals. After Jan. 18, 2020, the next will occur low in the morning sky on Dec. 27, 2021, when Mars will pass 4.5 degrees north of the star. On the next two occasions, on Dec. 8, 2023, and Nov. 18, 2025, Mars and Antares will appear too close to the sun to be seen from Earth. After those, the next visible conjunction of Mars-Antares will occur very low in evening sky on Oct. 29, 2027 (3.7 degrees apart). The next two, also in the evening, will be on Oct. 7, 2029 (3.3 degrees) and Sept. 10, 2031 (2.5 degrees). Then the Mars-Antares pairings shift back to mornings, on Feb. 25, 2033 (5.3 degrees) and Jan. 27, 2035 (4.9 degrees, similar to this year’s).

Saturn will be in conjunction with the sun on Jan. 13 and will follow Jupiter into the morning sky by early February. Then all three bright outer planets will be visible in morning sky, in a gathering that will become ever more compact until Mars passes the two giant planets late in March 2020.

For a preview of sky events through August 2020, with monthly all-sky charts for dusk and dawn, and graphs of planet rising and setting times, visit the Sky Calendar extra content page at www.abramsplanetarium.org/msta.

Check the website of the Astronomical Society of the Desert at www.astrorx.org for dates and times of our evening star parties.Our primary, more-accessible location is at the Visitor Center of the Santa Rosa and San Jacinto Mountains National Monument (on Highway 74, within 4 miles south of Highway 111 in Palm Desert). Our next session there will be on Saturday, Jan. 18, from 5 to 8 p.m. Sawmill Trailhead, our high-altitude site (elevation 4,000 feet), will have a star party starting at dusk on Saturday, Jan. 25.

Remember to check the Impromptu Star Parties link on the Astronomical Society’s webpage. I’ll be offering sky watches in Palm Springs at the pedestrian bridge over Tahquitz Creek at North Riverside Drive and Camino Real, and at other locations.

On Friday, Jan. 24, I will present a preview of sky events in 2020, including the year’s rare and beautiful planetary gatherings. The event will be at the Portola Community Center, 45480 Portola Ave., in Palm Desert. Doors open at 6:30 p.m. for refreshments, and the talk begins at 7 p.m.

Abrams Planetarium publishes a monthly Sky Calendar with an evening sky map. Subscriptions are $12 per year at www.abramsplanetarium.org/skycalendar for three printed issues mailed quarterly. The March 2020 issue of the calendar will feature the rare compact gathering of the three bright outer planets in predawn skies, and Venus ascending to its greatest height in the evening sky.

Wishing you an abundance of clear skies in 2020!

Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. Now retired, he often collaborates with John S. French on the Sky Calendar, and enjoys providing sky watching opportunities for a variety of groups. Robert D. Miller did graduate work in planetarium science and later astronomy and computer science at Michigan State University and remains active in research and public outreach in astronomy.

Published in Astronomy

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