The Sky This Week from January 24 to January 27
A total eclipse of the Moon Sunday night highlights a week that also boasts a stunning predawn conjunction between Venus and Jupiter.
Although Saturn passed on the opposite side of the Sun from Earth early this month, it already appears low in the southeast during morning twilight. From mid-northern latitudes, the ringed planet rises more than an hour before the Sun and climbs 5° above the horizon a half-hour before sunup. Saturn shines at magnitude 0.5, which makes it the brightest point of light in this part of the sky. Still, it won’t be easy to pick out of the bright twilight. To find it, use binoculars and scan to the lower left of Venus and Jupiter.
Friday, January 25
With the waning gibbous Moon now rising late in the evening, it’s a good time to look for Sirius. The night sky’s brightest star (at magnitude –1.5) appears prominent in the southeast as darkness falls and lies due south and at its highest elevation around 10 p.m. local time. From mid-northern latitudes, it then stands about one-third of the way from the horizon to the zenith. (The farther south you live, the higher it appears.) If you point binoculars at Sirius, look for the pretty star cluster M41 in the same field of view, just 4° south of the star.
Saturday, January 26
Mars continues to put on a nice show in January. Look for the Red Planet halfway to the zenith in the southwestern sky as darkness falls. The world shines at magnitude 0.8 against the much dimmer stars of southern Pisces. (Tonight, Mars slides 0.9° south of the 4th-magnitude star Epsilon () Piscium. A telescope reveals the planet’s 6″-diameter disk, but you likely won’t see any surface features unless you have exceptionally good seeing.
Sunday, January 27
Last Quarter Moon occurs at 4:10 p.m. EST. The Moon doesn’t rise until nearly 1 a.m. local time tomorrow morning, however, by which time it will appear slightly less than half-lit. The Moon spends the morning hours set against the background stars of northern Libra.