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

Our guide to planetary activity for January through March 2017.

The planet Mercury, image by NASA/JPL.

The smallest planet briefly pops out of the predawn twilight at the beginning of January, reaching greatest western elongation on the 19th, when it's angular distance from the Sun is 24.1 degrees and it rises in the southeast about an hour before the Sun. Dropping back into the Sun's glow, it's washed from view by early February and disappears behind the Sun until late-March, when it peeks out of the twilight just after sunset. The crescent Moon can be seen near Mercury on the morning of January 25. Its passage on February 25 takes place too close to the Sun to be seen, and its encounter on the evening of March 29, with Mars nearby may be a challenge very soon after sunset.

The planet venus, image by NASA/Caltec/JPL

The brightest planet is a prominent evening object almost all season, reaching It reaches greatest eastern elongation on January 12, meaning that its angular separation from the Sun is widest, and its sets more than 3 hours after the Sun. The combination of phase and apparent size adds up to Venus' greatest brilliancy on February 18, when knowledgeable skywatchers can find it in the daytime sky with binoculars. That also makes it an especially dazzling object after dark, and Venus remains visible in the evening until just before the equinox. After that, it retreats quickly back toward the Sun and reaches inferior conjunction on March 25. The Moon has a close pairing with Venus on the evenings of Jan 2 and 31 (with Mars nearby), and more distantly on February 28. Its pass on March 27 is too close to the Sun and washed from view by the glare.

The planet Mars, image by NASA

The Red Planet lingers near Venus in the early evening sky, slowly drawing near and making its closest on January 31, when the two are only 5 degrees apart and joined by the waxing crescent Moon. During the season, Mars gradually moves from the stars of Aquarius the Water-Carrier through Pisces the Fishes and into Aries the Ram. In early March, after Venus submerges into the twilight, Mars remains visible after dark, though gradually lower in the west each night, for the rest of the season. The Moon appears near Mars on the evenings of January 2 and 31 and March 1, 29, and 30.

The planet Jupiter, by NASA

The "King of the Planets" rises an hour after midnight at the beginning of January against the stars of Virgo the Maiden (near the bright star Spica). By the beginning of February, it rises almost an hour before midnight, and by March 1, it rises nearly 3 hours before midnight. As distant as it is, Jupiter moves very slowly against the stars and loiters near Spica for the entire season. The Moon appears nearby on the morning of January 19, and again on the nights of February 15 and 16, and March 14 and 15.

The planet Saturn, by NASA/JPL/Saturn institute

The Ringed Planet is just emerging from the predawn twilight at the start of the season, rising about 90 minutes before the Sun, and is gradually seen earlier each morning. For about the first week of January, sharp-eyed observers might glimpse Mercury to the lower-left of Saturn. Rising about 4 minutes earlier from one morning to the next, Saturn slowly becomes easier to see before dawn, and by mid-January it rises 2 hours before the Sun. On the morning of January 24, the nearby waning crescent Moon will help you find it. The Moon's passes near Saturn are easier to see on the mornings of February 20 and March 20, when they rise together about 3 and 4½ hours before dawn, respectively.

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Planetarium by Night

Planetarium by Night

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2017 Pocket Almanac

2017 Pocket Almanac

Download the Morrison Planetarium's 2017 Pocket Almanac to stay up-to-date on eclipses, meteor showers, satellite spottings, and more.

2017 Morrison Planetarium pocket almanac