August Sky Chart; Northern Hemisphere gazer's guide

Aug. 3-4: After passing above Venus on the 2nd, the moom advances toward Jupiter and Saturn on the 3rd, passes above them early next morning, and moves away from them on the evening of the 4th. The two planets and the moon will be easily visible in the west on both evenings from an hour or so after sundown until they set several hours before midnight. Venus, below them on both nights, sets about an hour before Jupiter.

Aug. 9: The reddish star near the waxing gibbous moon tonight is Antares, in Scorpius.

Aug. 10-14: These are the dates to look for the Perseid meteors this year, the best meteor shower of the Northern Hemisphere, usually the most reliable and productive, with swift, bright, often spectacular meteors and fireballs. Maximum for the shower occurs on the morning of the 12th, and the waxing gibbous moon sets that morning at about 2 a.m. standard time, just about the time that seeing conditions should be approaching their best. At maximum, an observer may expect to see 50 or more shower meteors per hour, many leaving lighted trains in their path, often bursting. The brightest rival or surpass Venus. The Perseids are so reliable that you can't miss them if skies are clear and you watch patiently for at least half an hour after 2 a.m. Remember, however, that shower meteors may appear anywhere in the sky; be sure to look from a position that allows you to see as much of the sky as possible.

Aug. 23: Mars is rising earlier now, climbing sharply into the sky before dawn. Today it passes south of Pollux, in Gemini, and the twin stars Pollux and Castor become triplets. Mars is the lowest of the three, all well up in the east, about as bright as Castor, the uppermost of the "twins."

Aug. 25-27: Venus has been moving slowly east through the stars, toward Jupiter and Saturn, while the latter, in turn, have been setting earlier each night as the sun approaches them. The distances separating Jupiter and Saturn from Venus has been diminishing slowly since the beginning of Aug., and now slowly since the beginning of aug., and now they all appear together in the evening twilight, setting about an hour or so after they become visible in the west. Venus passes below Saturn on the 25th, below Jupiter on the 27th. Thursday night the two brightest planets in our sky, Venus and Jupiter, will be exceptionally close. Venus is the lower of the two, and Saturn is above Jupiter.

Aug. 31: The waxing crescent moon may be visible tonight, 2 1/2 days after it is new. It passes above Saturn at about 8 p.m., Eastern standard time, above Jupiter at about 1 a.m. and above Venus at 10 a.m. on Sept. 1. Since Venus has not yet separated very far to the east of Jupiter, the four objects (moon, venus , Jupiter, and Saturn) will make an exceptional group in the twilight sky. But look for them early. They will be setting within two hours of the sun. The star Spica, in virgo, is also nearby, to the left and above.

All Month: An interesting gathering of planets in the early evening sky builds gradually through Aug., eventually including Jupiter, Saturn, Venus, Mercury, and the moon. Start watching early in the month to follow its development.

On Aug. 1, Venus is located low in the west shortly after sunset, very low and very bright from half an hour after sundown until it sets roughly an hour later. To the left and above, Jupiter -- brighter than any star -- should be visible shortly after Venus, then a little later Saturn, to Jupiter's right, and Spica (in Virgo), to its left (and more distant). On the evenings of Aug. 2, 3, and 4 the early crescent moon moves past, above Venus on the 2nd, near Saturn and Jupiter on the 3rd, near Spica on the 4th. Jupiter and Saturn set about an hour after Venus.

During the month, Venus moves eastward swiftly, both Jupiter and Saturn more slowly. Equally important: the sun is also shifting easterly through the stars, keeping pace with Venus but approaching Jupiter and Saturn, causing them to set later with each passing night. As a result, Jupiter separates slowly to Saturn's left, Venus moves closer to both of them, and all three planets approach spica. Jupiter and Saturn appear lower in the sky each night and closer to Venus, setting with it by month's end. On aug. 25, Venus passes Saturn, then Jupiter on Aug. 29. Mercury, meantime, is creeping up on them from the west, and then on Aug. 30 the early crescent moon moves into view again.

If conditions are good, the nights of Aug. 30 and 31 and Sept. 1 should be exceptional. Look early, beginning about half an hour after sundown. Venus, Jupiter, and Saturn will be standing in line horizontally in the sunset. The crescent moon of the 30th (a day and a half old) will be lower and to their right, and Mercury below it. On the 31st the moon will be more easily visible above Saturn and Jupiter, and on Sept. 1 still higher, to the left and above the bright planets.