The Moon visits Venus and Mars, while Jupiter climbs higher.
The evening sky is home to two planets, or could it be three? Venus and Mars are obvious. Venus shines at magnitude –4.2 and can be seen low in the south-southwest even in bright twilight. At magnitude 0.6, Mars requires a darker sky, but it’s among the first points of light to emerge in the south, above and to the left of Venus, as dusk begins to fade. The “maybe” planet is Mercury. It’s a magnitude –0.5 point of light near the southwest horizon and sets a little less than an hour after the Sun. To spot the fast-moving little world you’re going to need a flat horizon and probably a pair of binoculars. If you don’t succeed, take heart—Mercury will be higher next week. Our final, and best, planetary offering is a morning object. Shining at magnitude –1.8, Jupiter rises around 3 a.m., local standard time. By the first hint of dawn, Jupiter has climbed to an altitude of 30 degrees—high enough for satisfying views in a telescope at moderate magnification.
The Moon is new this morning at 7:18 a.m., EST.
On both December 2 and 3, the crescent Moon is positioned near brilliant Venus. As shown in the illustration above, one evening the Moon shines to the planet’s right, on the next it’s to the left.
After passing Venus, the Moon continues its eastward journey and approaches Mars. On December 4 the lunar crescent lies west of the red planet; on December 5, it’s east of it. The Moon will be roughly 6 degrees from Mars each night.
There are plenty of dark hours available in the over the December 2 – 4 weekend, but you’ll have to wait until the Moon sets in the early evening. By then, the lingering constellations of summer are setting in the west while the bright stars of winter are rising in the east. Between them, straddling the meridian are the autumn constellations. The words big and dim best characterize most of these groups—especially in contrast to the ones populating the summer and winter skies. That makes finding your way a little trickier if you’re a new stargazer, and doubly so you’re observing in light-polluted conditions.
Autumn’s most distinctive constellations are Capricornus, Pegasus, Andromeda and Cassiopeia. Yet none of these features a star brighter than magnitude 2. Cassiopeia is probably the easiest to make out, and a good place to start a sky tour since its distinctive W shape is almost directly overhead and is a snap to visualize. Next, try to locate the Great Square of Pegasus high in the south. Once you have that in sight, finding the two curving rows of stars making up Andromeda is much easier. Lastly, head southwest to find the squashed V of Capricornus. It’s more difficult to spot than the other constellations I’ve just described, but only by a little. And, thankfully, you have Mars to help guide you, as the chart above shows. (The crescent Moon will drift into Capricornus this weekend as well.)
Once you’ve found the main constellations, expand your search to the season’s less conspicuous star patterns: Pisces, Cetus, Aquarius and Cepheus. If you can identify all of them, you’ve truly mastered the autumn sky!
At SkyNews we love to read about your experiences and see your photos. You can share them with us by e-mailing firstname.lastname@example.org.