Lunar Phases  September 3  September 11  September 17  September 25

September 2005
Vega remains the brightest star high overhead at dusk. Arcturus is the brightest in the west, dropping lower week by week. Look to the right of Arcturus for the Big Dipper declining in the northwest, a departing sign of summer. A little higher in the northeast, look for W-shaped Cassiopeia, a rising sign of the coming fall and winter. The right-hand side of the W (its brighter side) is tilted up. In late evening, bright orange Mars rises in the east, far to Cassiopeia's lower right.

1 Look for the waning crescent Moon hanging in the eastern sky as dawn begins to grow bright. Saturn is to its upper right. Look below the Moon, near the horizon, for Mercury; binoculars help.

2 Venus and Jupiter are in conjunction just above the western horizon in evening twilight. Look for Jupiter only 1 ¹/₄ degrees (a bit less than a finger-width at arm's length) to the upper right of brighter Venus. Fainter Spica is to Venus' left by 4 ¹/₂ degrees.

3 Jupiter, bright Venus, and faint Spica form a short, nearly horizontal line just above the western horizon in twilight, in that order from right to left.

6 Look just above the west-southwest horizon in bright twilight for Venus, Jupiter, and the thin crescent Moon forming a triangle. Spica is barely below Venus. Binoculars give a fine view.

7 Just above the west-southwest horizon in twilight, the Moon, Venus (with Spica just below it), and Jupiter form a line, in that order from left to right.

10 The orange-tinted star to the right of the Moon this evening is Antares. Delta Scorpii is farther right.

12 Look for Venus and Jupiter just above the west-southwest horizon in bright twilight, about 40 minutes after sunset. They've now separated to about a fist-width at arm's length. (Jupiter is the fainter one, on the right.) Spica is below the midpoint between them -- but to see it, you may need binoculars.

16 The Moon is at perigee.

17 Harvest Moon.

21 By about 10 p.m. the Moon is up in the east, with Mars shining to its lower right. Mars is brightening as it nears Earth for a close pass in late October and early November.

22 The autumnal equinox occurs at 5:23 p.m. CDT. This is when the Sun crosses the equator heading south for the year, marking the start of fall in the northern hemisphere and spring in the southern hemisphere.

28 Before and during dawn, Saturn shines to the right of the Moon. Procyon is much farther to their right. Brilliant Sirius is even farther to Procyon's right (and probably somewhat lower). Orion stands above Sirius. The Moon is at apogee.