Skywatch Line for Friday, October 18, through Sunday, October 20, written by Sam Salem

This is Dudley Observatory’s Skywatch Line for Friday, October 18, through Sunday, October 20, written by Sam Salem.

On Friday, Sun rises at 7:13am and sets at 6:07pm; Moon sets at 8:42am and rises at 6:38pm.

Soon after sunset on Friday and Saturday, the waning gibbous Moon will move closer to Jupiter. The Pleiades star cluster will shine nearby and will be closest to the Moon on Saturday. Orange star Aldebaran, the Eye of Taurus the Bull, will shine near Jupiter.

On the Sunday evening, the waning gibbous Moon will slide between Jupiter and Capella, the brightest star in Auriga the charioteer. Near Jupiter lies the Aldebaran. Pleiades star cluster will be nearby. They’ll rise a few hours after sunset and be visible through dawn.

The greatest number of Orionid meteors should zip across the sky on the Sunday and Monday mornings. The Orionid meteor shower should be active in the hours before dawn Sunday morning, but don’t expect to see many at all through the waning gibbous moonlight. Under ideal conditions you might see up to 20 meteors per hour. The radiant, in Orion’s upraised club, will be high in the southeast to south by then.

Locate Deneb in the night sky. Deneb has replaced Vega as the zenith star after nightfall for skywatchers at mid-northern latitudes. Accordingly, Capricornus has replaced Sagittarius as the zodiacal constellation posing low in the south.

Before dawn Sunday, catch Pollux, Mars, and Procyon forming a straight line, in that order from upper left to lower right. The three shine with similar brightnesses: magnitudes +1.1, +0.3, and +0.4, respectively. Pollux is three times closer to Mars than Procyon is. Mars is moving eastward against the stars fast. On Monday morning the line won’t be so straight.

Mars, at magnitude +0.3, in the constellation of Gemini, rises around midnight. It shows best, very high in the southeast, in the hour before dawn. It’s now 30° down east of bright Jupiter. Mars in a telescope is still a small 8 arcseconds wide.

Venus, magnitude –3.9, gleams low in the southwest as evening twilight fades. It sets around twilight’s end.

Saturn, magnitude +0.7 in the constellation of Aquarius, is well up in the southeast as the stars come out. Don’t confuse it with Fomalhaut two fists to its lower right. Saturn is highest in the south by about 10 p.m.