Solar system showing relative size of (but not distance between) planets.

Keep tabs on our planets with Morrison Planetarium's quarterly guide to planetary activity.


The planet Mercury, image by NASA/JPL

The smallest and most elusive of the naked-eye planets spends pretty much all of October in the predawn sky, located west of the Sun. It's most visible when its angular separation from the Sun reaches 18° on October 8 (greatest western elongation) and it rises an hour and a half before dawn. Then, it quickly drops into the Sun's bright glow and is washed from sight in the weeks surrounding superior conjunction (November 8), when it's located on the other side of the Sun from Earth and slowly moves into the evening sky. Joining Venus low in the west after sunset in late-November, it reaches its greatest eastern elongation—its greatest separation east of the Sun (20.1°)—on December 21, setting about an hour and a half after sunset.

The Moon is located near Mercury in the sky on the morning of October 24 and the evening of November 24, but these pairings are hidden by the Sun's glare. Their pairing on the evening of December 24 is far enough away from the Sun to be seen very low in the southwest an hour after sunset.



The planet venus, image by NASA/Caltech/JPL

Venus spends most of the season hidden in the Sun's glow, reaching superior conjunction on October 22, when it passes behind the Sun and slowly enters the evening sky, becoming visible at the end of December. Back in January, it was six times the diameter we see at this time. Did it shrink? Explanation in Highlights.

The Moon passes near Venus on October 25 and November 24, but those encounters are too close to the Sun and are obliterated by the glare. Their next meeting on the evening of December 24 will be a challenge to see, occurring only a day after new and located very low in the west after sunset, just emerging out of the twilight.



The planet Mars, image by NASA

The Red Planet rises at about 10:30 pm on October 1, around 8:40 pm on November 1, and at about 5 pm on December 1 (the extra-hour jump courtesy of the change back to Standard Time on November 6). On December 7, it reaches opposition, rising at sunset, and observers in most US locations will see the Moon pass in front of Mars, blocking it from view (called an occultation). Details of this event are in Highlights.

The Moon swings past Mars on the nights of October 14, November 10, and, for certain areas, plows right over it for the occultation on December 7.



The planet Jupiter, by NASA

The largest of the planets reached opposition in late September, meaning that it rises at about sunset. Through the rest of the season, it gradually spends less and less time in the night sky, rising at about 6:30 pm on October 1, at about 4:30 pm on November 1, and at about 1:30 pm on December 1. Jupiter begins the season moving from east to west against the stars. Then, on November 24, it seems to stop and reverse its motion, resuming its normal west-to-east traverse. It's not that Jupiter can't make up its mind which way it wants to go—this is a perceptual phenomenon called retrograde motion that occurs near opposition as Earth passes the slower-moving Jupiter, making it appear to move backward.

The Moon swings past Jupiter on October 8, November 4, December 1, and for the second time that month on December 28 and 29.



The planet Saturn, by NASA/JPL/Saturn institute

On October 1, the most distant of the naked-eye planets rises at 4:44 pm and is already visible in the southeast by nightfall, located in Capricornus the Sea-Goat. On November 1, it rises at 2:30 in the afternoon, and on December 1, it rises around 11:30 am.

The Moon can be seen pairing up with the Ringed Planet on October 5, November 1, November 28, and December 26.


Sunrise and sunset table

Times are for San Francisco, California, and will vary slightly for other locations.

October 1 (PDT)
Sunrise | Solar Noon | Sunset
7:05 am | 12:59 pm | 6:52 pm 

November 1 (PDT)
Sunrise | Solar Noon | Sunset
7:34 am | 12:53 pm | 6:11 pm

December 1 (PST) 
Sunrise | Solar Noon | Sunset
7:06 am | 11:58 am | 4:41 pm