Skywatch Line for Friday, November 17, through Sunday, November 19, 2023

This is Dudley Observatory’s Skywatch Line for Friday, November 17, through Sunday, November 19, written by Sam Salem.

On Friday, Sun rises at 6:49am and sets at 4:31pm; Moon rises at 11:30am and sets at 8:05pm.

Look south-southwest at nightfall on Friday for the waxing crescent Moon. It forms a huge, nearly equilateral triangle with Saturn far to its upper left and Altair far to its upper right. Each side of the triangle is nearly four fists at arm’s length long. On Sunday evening and Monday evening, the Moon passes Saturn while going through first-quarter phase.

Saturn, at magnitude +0.7 in dim Aquarius, glows steady yellowish high in the south in early evening. The similarly bright star, Fomalhaut, twinkles almost two fists at arm’s length to Saturn’s lower left.

Jupiter, at magnitude –2.9 in the constellation of Aries, is a little past its November 2nd opposition. It dominates the east during evening, stands highest in the south around 11pm. It sets before sunrise. In a telescope Jupiter is still around 49 or 48 arcseconds wide, nearly as big as we ever see it.

Uranus, at magnitude 5.6 in the constellation of Aries, is 12° east of Jupiter. It’s a little past its opposition on November 13th. In a telescope at high power Uranus is a tiny but distinctly non-stellar ball, 3.8 arcseconds in diameter.

Neptune, at magnitude 7.8 at the Aquarius-Pisces border, is high in early evening, 24° east of Saturn. Neptune is only 2.3 arcseconds wide, harder to resolve as a ball than Uranus is, but non-stellar at high power.

Venus, brilliant at magnitude –4.4, shines in the east-southeast before and during dawn. It rises 2 hours before dawn’s first light. Watch Venus passing much fainter 3rd magnitude star, Gamma Virginis. They appear closest together on Friday morning, with Gamma Virginis 1.2° to Venus’s left. Gamma Virginis, or Porrima, is a fine telescopic binary star in the constellation of Virgo.

Orion is clearing the eastern horizon by about 8pm. Above Orion shines orange star Aldebaran in the constellation of Taurus. Above Aldebaran is the little Pleiades cluster, the size of your fingertip at arm’s length. Far left of Aldebaran and the Pleiades is bright star Capella in the northern constellation of Auriga. Down below Orion, bright star Sirius rises around 10pm. No matter where in the sky they are, Sirius always follows two hours behind Orion.