On October 30 and 31, 2019, watch for two brilliant luminaries – the crescent moon and the dazzling planet Jupiter – to pop out near one another as dusk deepens into nightfall. Given clear skies, you’ll have no trouble seeing either world, because they are so bright! The moon is the 2nd-brightest sky object (after the sun). Jupiter is 4th-brightest (after Venus).
By early November, a larger crescent moon will have left the king planet Jupiter behind to join up with the ringed planet Saturn, the sixth planet from the sun and second-largest planet in our solar system.
Click here to find a sky almanac providing you with the setting times for the sun, moon and planets in your sky.
The moon, planets and stars will all move westward as evening deepens into late night.
All these celestial objects move westward across the sky for the same reason that the sun moves westward during the day. This apparent motion in our sky is really a reflection of Earth’s spin on its axis from west to east. Earth’s spin makes it appear as if the sun, stars, moon and planets all travel westward around the Earth each day.
All the while, however, the moon is moving eastward relative to the stars and planets of the zodiac. The moon travels about 1/2 degree (its own angular diameter) eastward per hour or about 13 degrees eastward per day. Day by day, at the same time, note the moon’s change of position relative to the backdrop stars and planets. The moon’s change of position is due to the moon’s orbital motion.
Bottom line: On October 30 and 31, 2019, as darkness falls, look for the brilliant “star” by the moon. That’ll be Jupiter, 5th planet from the sun and our solar system’s largest planet. By November 1 and 2, the moon will be closer to Saturn.
Bruce McClure has served as lead writer for EarthSky's popular Tonight pages since 2004. He's a sundial aficionado, whose love for the heavens has taken him to Lake Titicaca in Bolivia and sailing in the North Atlantic, where he earned his celestial navigation certificate through the School of Ocean Sailing and Navigation. He also writes and hosts public astronomy programs and planetarium programs in and around his home in upstate New York.