Saturn is the only planet in May 2011 evening skies. Face south southeast at dusk, and you’ll see Saturn near a star of similar brightness— Spica in Virgo. Saturn is significantly higher in the sky than Spica and a bit to its right as you face south. Last month, Earth passed between the Sun and Saturn. That alignment, called opposition, put Saturn in the sky all night long. The ringed planet is now well placed for evening viewing, and remains in the evening sky until late September 2011.
photo credit: chipdatajeffb
The other four naked eye planets are involved in a very close gathering low in the east at dawn. You will need a clear view all the way to the east northeastern horizon at daybreak to observe this planet massing. However, the planets do outshine all stars in this general area. If you’re able to observe any points of light just above the horizon as dawn begins, you’re probably seeing the planets. As of now, Venus and Mercury rise first, with Mercury about a degree under the brighter Venus. Mars and Jupiter are a bit to their lower left, with Mars a little to the left of Jupiter. Mars was less that half a degree above Jupiter on May 1, and is now slowly pulling away from it. Venus and Mercury are moving faster, so they are closing the gap on Mars and Jupiter.
On the morning of May 11, Venus and Mercury will be aligned with Jupiter, with Venus less than one degree from Jupiter. This is also when the entire grouping is the most compact, with all four planets within six degrees of one another. By May 21, Mercury and Venus will have caught up with Mars, with Venus just over a degree from the red planet. After this, Mercury and Venus pull ahead of Mars and thus go deeper into the sun’s glare. Mars and Jupiter, left behind, remain in the morning sky all summer.
|photo credit: jurvetson|
A swath of brilliant winter stars sets in the west at dusk this month. Orion, the Hunter, is still visible in the west as May begins. His two dogs, represented by Sirius and Procyon, are to his left. To Orion’s right is Taurus, the Bull, with the star Aldebaran as its eye. Gemini, the Twins, are above Orion. The Big Dipper is above the North Star, with its handle pointing to the right. From that handle, you can ‘arc to Arcturus’ and then ‘speed on to Spica;’ those stars are in the east and southeast at dusk. Leo, the Lion, passes almost overhead in late evening.
As Orion and Taurus set, look for Antares, brightest star of Scorpius, the Scorpion, to rise in the southeast. At the same time, Vega, brightest star of the Summer Triangle, appears low in the northeast. These stars remind us that summer is on the way.
Moon Phases in May 2011:
New Moon May 3, 1:50 a.m.
1st Quarter May 10, 3:32 p.m.
Full Moon May 17, 6:07 a.m.
Last Quarter May 24, 1:51 p.m.