The sky in February

At the beginning of February Mercury has just passed behind the Sun and sets too soon after sunset to be seen. But by the 9th the speedy planet should be visible to viewers with binoculars, just above the west-southwestern horizon near where the Sun has disappeared half an hour earlier. By the 14th Mercury sets a full hour after the Sun and is easy to see with the naked eye.

The planet reaches greatest eastern elongation (its greatest angular distance from the Sun) on the 23rd, only a day after it passes perihelion (its closest approach to the Sun). That makes for favorable observing in the mid-northern United States, because Mercury is almost directly above the Sun, giving the planet more time to shine in a dark sky before setting at the end of twilight. A slender crescent Moon hangs about five and a half degrees below and slightly to the left of Mercury on the 28th.

Venus rises in a dark sky about half an hour before morning twilight at the beginning of February; it rises nearly half an hour earlier by month's end. The planet is scooting ahead of the Earth as it races around the Sun, so viewers with telescopes will see the crescent of Venus thickening in phase but diminishing in overall size. Venus reaches its greatest brilliancy of the year--a stunning -4.6 magnitude--on the 17th.

Mars soars high in the sky this month. It is near the meridian at dusk and remains visible until about an hour to an hour and a half after midnight. On the evening of the 5th Mars is situated about two to three degrees below the Moon. The planet moves east nearly fifteen degrees this month, crossing from the constellations Aries, the ram, into Taurus, the bull, on the 7th.

If you watch attentively, you may be able to detect changes in the color of the Red Planet. In fact, despite its nickname, Mars usually looks yellow to yellow-orange. During its occasional global dust storms, however, it becomes a lighter yellow.

Jupiter, in the constellation Libra, the scales, rises just after 1 A.M. at the start of February and shortly before 11:30 P.M. near month's end. But for the best views, look before morning twilight begins, when the planet is well up in the south. Soon after midnight on the 20th Jupiter rises about five to six degrees above and to the left of the waning gibbous Moon.

Saturn, just past its opposition of January 27th, is low in the east at dusk and visible for most of the night. The planet begins the month one degree south of Praesepe, the Beehive star cluster in the constellation Cancer, the crab. Soon after darkness on the 10th, the Moon appears to stand high above the planet in the east. On the following evening our satellite shifts below and to the left of Saturn.

The Moon waxes to first quarter on the 5th at 1:29 a.m. and to full on the 12th at 11:44 P.M. It wanes to last quarter on the 21st at 2:17 A.M. and to new on the 27th at 7:31 P.M.

Late on the night of the 17th a waning gibbous Moon occults, or passes in front of, Spica, a bright, bluish, first-magnitude star in the constellation Virgo, the virgin. Unfortunately for most viewers in the United States, the event is unobservable because it takes place before the Moon and Spica rise. In the Northeast, however, Spica will already be hidden when the Moon rises, after about 10 P.M. Soon after 11 P.M., while still low and near the east-southeastern horizon, Spica dramatically pops out from behind the dark part of the Moon as viewed with binoculars or a telescope.

Unless otherwise noted, all times are given in eastern standard time.

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