Abrams Planetarium

SKYWATCHER'S DIARY: May 1995

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Sky Calendar
Abrams Planetarium
Michigan State University
East Lansing, MI 48824

This month's most striking sights include a close pairing of Mars with the star Regulus for a few evenings around May 24, and the moon passing near planets and bright stars, on the evenings of May 1, 3, 5, 7, 8, 12, and 15, and the mornings of May 16, 23, 26 and 27. Morning events are mentioned in Skywatcher's Guide one day prior to the event.

National Astronomy Day

Sunday, April 30 (included because it's the first day of the new lunar cycle)

Look early, half an hour after sunset, for the young moon very low in WNW. Binoculars give the best view of the delicate crescent, only 31-1/2 hours after New from mid-lower Michigan. Mercury is 5 degrees to moon's upper right. As the sky darkens, binoculars show the Pleiades star cluster 3 degrees above Mercury.

Monday, May 1

At dusk face WNW to find the slender crescent moon with Mercury 9 degrees to its lower right. Use binoculars to see the Pleiades star cluster 2 degrees to Mercury's upper right. Aldebaran in Taurus shines 4 degrees upper left of the moon. That bluish glow you see on the moon's dark side for the next few nights is earthshine, or sunlight reflected from Earth to illuminate the moon.

Tuesday, May 2

An hour after sundown the waxing crescent moon is in the W to WNW with reddish Aldebaran, the eye of the Bull, 8 degrees to its lower right. Mercury, at its best for this year now through mid-May, is 18 degrees lower right of the crescent tonight. Use binoculars to see Taurus' two famous star clusters in the glow of twilight: The Pleiades, or Seven Sisters, 2 degrees to Mercury's right, and the Hyades below and right of Aldebaran.

Wednesday, May 3

At dusk the moon is in the W with ruddy Betelgeuse 11 degrees lower left.

Thursday, May 4

At dusk the moon, well up in W, is encircled by bright stars, each about 17 degrees from the moon. Procyon is to the moon's left. Betelgeuse, below the moon, marks the shoulder of Orion the Hunter. The Gemini Twins, Pollux and Castor, shine above the moon.

Friday, May 5

As darkness falls the moon is high in the WSW to W with zero-magnitude Procyon 10 degrees to its lower left. The Gemini Twins, Pollux and slightly fainter Castor, are 12 and 16 degrees upper right of the crescent moon.

To commemorate National Astronomy Day (Saturday, May 6), Abrams Planetarium presents Spring and Summer Skies, this weekend only, with showings tonight and Saturday at 8 p.m., and Sunday at 4 p.m. After the evening shows, the MSU Observatory will be open for viewing if skies are clear. If we're not nearby, check with the planetarium or astronomy club in your area to see what they're offering this weekend and join in!

Saturday, May 6

An hour after sunset the moon, approaching First Quarter, is high in the WSW with the Little Dog Star, Procyon, 14 degrees lower right. Pollux and Castor are to the right of the slightly less than half full moon. Two hours later, look low over the SE horizon for bright Jupiter rising with reddish twinkling Antares 7 degrees to its lower right.

Spring and Summer Skies, 8 p.m. tonight at Abrams Planetarium. MSU Observatory will be open after show if skies are clear. The last showing of Spring and Summer Skies will be at 4 p.m. Sunday.

Sunday, May 7

An hour after sunset the First Quarter moon is high in the SW with reddish Mars 9 degrees to its upper left.. Regulus, in Leo, shines 7 degrees left of Mars and 13 degrees to moon's upper left. At the same time tomorrow evening the moon will be 13 degrees farther east against background stars. Can you predict where will it appear?

Monday, May 8

An hour after sunset the waxing gibbous moon is in the SSW with bluish first-magnitude Regulus 6 degrees its upper right. Regulus represents the heart of Leo the Lion, and marks the handle of the Sickle, whose blade forms the lion's mane. Ruddy Mars, now double the brightness of Regulus, lies 11 degrees upper right of the moon and 7 degrees from the star.

Tuesday, May 9

At dusk look very low in the WNW for elusive Mercury, this week at its highest and best for the year. Tonight Betelgeuse in Orion shines in west, 26 degrees to Mercury's left and a few degrees higher. Binoculars may be needed to spot departing Aldebaran, 8 degrees lower left of the planet.

Wednesday, May 10

Can you see the three naked-eye planets now in the morning sky? At dawn Thursday look low in the SW for bright Jupiter with reddish Antares 6 degrees to its lower right. Turn to face ESE for a glimpse of yellowish Saturn. Telescopes may show this planet's rings, only 0.4 degrees from edgewise, as an extremely thin line. Lower left of Saturn, by 30 degrees, is brilliant Venus just rising north of due east.

Thursday, May 11

An hour after sunset the moon is in the SSE with Spica 11 degrees to its lower left. The moon, nearing perigee (closest to Earth), is moving faster than usual in its orbit; can you guess where it will appear tomorrow evening at this time?

Friday, May 12

The moon is well up in the SE at dusk. Bluish Spica, the spike of wheat in the hand of Virgo, shines about 4 degrees to the moon's upper right.

Saturday, May 13

The moon, approaching Full, is in the SE at dusk. Binoculars show the star Alpha in Libra, or Zubenelgenubi, closely lower left of the moon as darkness falls. Seen from parts of western and southern U.S. later tonight, the moon occults or covers the star. Since the moon is very bright, a telescope will be required to see the event. From Los Angeles the star disappears at 11:02 p.m. PDT; from Austin TX at 1:56 a.m. CDT; and from Miami FL at 3:29 a.m. EDT. From most of the U.S., the moon will pass narrowly south of the star. Spica, in Virgo, shines nearly 20 degrees to moon's upper right.

Sunday, May 14

The Full Moon rises in the ESE within a few minutes after sunset. Two hours later, the "Planting Moon" is higher, with bright Jupiter rising within 15 degrees to moon's lower left. Look for reddish twinkling Antares 6 degrees to Jupiter's lower right. An hour before sunrise Monday the moon is low in the SW. Jupiter is then 12 degrees upper left of the moon, with Antares 6 degrees below the bright planet.

Monday, May 15

Two hours after sunset the waning gibbous moon is very low in the SE with bright Jupiter within 2 degrees to its right. Antares in Scorpius is 8 degrees lower right of the moon. An hour before sunup Tuesday, look for the moon low in the SSW to SW, with Jupiter and Antares to moon's lower right, by 4 degrees and 10 degrees, respectively.

Tuesday, May 16

An hour after sunset look high in the north for the seven bright stars of the Big Dipper. Then "Follow the arc (of the handle of the Dipper) to Arcturus, and drive a spike to Spica."

Wednesday, May 17

For how many more nights will the remaining few bright stars of winter still be visible? In deepening twilight each clear evening in coming weeks, watch Betelgeuse, Procyon, the Twins of Gemini, and the Mother Goat star Capella sink into the western twilight glow. Keep a daily log of your observations, and try to see each star on its last possible date.

Thursday, May 18

Three-quarters of an hour after sundown, Mercury is at magnitude 1.4 and fainter each night. Locate the Mother Goat star Capella, in the NW, and look for Mercury very low in WNW, 22 degrees to Capella's lower left. In a few days, Mercury will be gone.

Friday, May 19

Look high in the SW at dusk to see Mars and Regulus 2.5 degrees apart and closing. Look nightly as Mars continues to advance towards first-magnitude Regulus, the star which marks the heart of Leo the Lion. In the middle of next week the pair appears at its closest!

Saturday, May 20

Sunday morning is our last chance until August to observe the illuminated north face of Saturn's rings. For the first time since 1980, the angle of inclination of the ring plane diminishes to 0 degrees on May 22 as the rings present themselves edge-on to Earth. Saturn is low in the ESE at dawn, and a high-quality telescope is needed to observe the hairline-thin rings before they "disappear"! Much easier than the rings will be a thin black line across the disk of Saturn -- the shadow of the rings! Locate Saturn to the lower left of the moon an hour before sunup on Sunday and Monday.

Sunday, May 21

Follow Mars and Regulus high in the SW at dusk nightly; they're closest this Wednesday. An hour before sunrise Monday morning the moon is in the ESE with Saturn 12 degrees to its lower left. If observed with a telescope, Saturn appears "ringless" until August as the rings' unlit southern face is tipped slightly into our view.

Monday, May 22

The slender waning crescent moon is in ESE at dawn Tuesday as it pulls about even with yellowish Saturn, 5 degrees to moon's lower right. Bright Venus, just rising N of E, lies far lower left of the moon. If you can't spot Venus, wait until it rises above any features of your landscape that might block your view.

Tuesday, May 23

Mars and Regulus are at their closest Wednesday evening; look nightly and watch for changes. The thin crescent moon is in E to ESE an hour before sunup Wednesday. Look for the "ringless" planet Saturn 15 degrees to the moon's upper right.

Wednesday, May 24

At dusk look high in the SW as reddish Mars passes 1 degree N of bluish Regulus in Leo. Binoculars enhance the pair's beautiful color contrast. The next pairing of these two bright objects is in October 1996 at dawn. Their next two evening pairings are not until July 22, 2006 and July 1, 2008. So, enjoy this one!

Thursday, May 25

Half an hour before sunup Friday, the thin crescent moon is very low in the east with the brilliant "morning star" Venus 9 degrees to its lower left.

Friday, May 26

Look early, 30 minutes before sunrise Saturday, for the old moon very low in ENE to E. Note the old crescent "bowl" appears tipped on its side, as if pouring its water out. Brilliant Venus is within 2 degrees upper right of the crescent. Binoculars help locate the thin crescent in bright twilight.

Saturday, May 27

An hour after sunset look high in the N to locate the seven bright stars of the Big Dipper. The two stars in the front of the bowl of the dipper are called the Pointer Stars, because a line connecting them, extended one Big Dipper length downward, points to the North Star, Polaris. This second-magnitude star marks the end of the handle of the fainter Little Dipper. The 2nd- and 3rd-magnitude "Guardians of the Pole", in the bowl of the Little Dipper, can be found near a line connecting Polaris to the end of the Big Dipper's handle.

Sunday, May 28

The New moon will occur overnight tonight, on Monday at 5:27 a.m. EDT. The moon, appearing very near the Sun, is not visible until early Tuesday evening. New moon marks the end of one cycle of lunar phases and the beginning of another, hence the term "new".

Monday, May 29

At dusk look high in the SW as ruddy Mars and bluish first-magnitude Regulus are 2.5 degrees apart and widening nightly. Note their separation again a week from tonight, when the Moon will pass nearby.

Tuesday, May 30

Look early, half an hour after sunset, for the young moon very low in the WNW. Binoculars will aid in the search for the thin crescent, some 40 hours after New from lower Michigan. As twilight fades, Capella in Auriga is in the NW, far upper right of the setting crescent, while Procyon shines in the W, far to the moon's upper left.

Wednesday, May 31

An hour after sunset the thin waxing crescent moon is very low in the WNW. The Gemini Twins, Pollux and slightly fainter Castor, shine high above the moon. Procyon, the Little Dog Star, lies far upper left of the moon. Bright Jupiter, low in SE at dusk, is visible all night. Look for it again low in SW at dawn.

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