In the Sky This Month

Look for the Moon before and during dawn tomorrow. Antares, the bright orange star that represents the heart of the scorpion, is close to its lower right.

Virgo, the constellation perhaps most identified with spring, is entering prime evening viewing time. Most of its stars are relatively faint. But Virgo’s brightest star, blue-white Spica, is easy to pick out. It rises in the east by about 10:30 p.m.

The star at the middle of the Orion’s Belt could be the most impressive of the belt’s three stars. Alnilam is at least 30 times the mass of the Sun, and 275,000 times brighter. But it could be twice as massive as that, and three times as bright.

Orion’s Belt is in the south-southwest as night falls. The star at the left end is Alnitak. It’s a system that includes two supergiants, which are among the biggest, brightest, and heaviest stars in the galaxy.

Orion’s Belt is one of the easiest star patterns to recognize. It’s a line of three fairly bright stars, with a slight dip at the left end. From most of the U.S., it’s about halfway up the south-southwestern sky as darkness falls at this time of year.

Canopus, the second-brightest star in the night sky, is in view on winter nights for those who you live south of about Dallas. It is well below Sirius, the night sky’s brightest star. Canopus is due south in early evening, just above the horizon.

Some of the brightest stars in the night sky are visible tonight. Sirius, the brightest of them all, is in the south at nightfall. Orion is to its upper right. And Regulus, near the Moon, and Aldebaran, near Orion, add to the lightshow.

Venus, the “evening star,” points the way to a much fainter planet tonight. Uranus, the seventh planet from the Sun, is to the left of Venus by two or three degrees. Through binoculars, Uranus looks like a small, faint star.

The constellation Coma Berenices (Berenice’s Hair) stands well to the lower right of the Big Dipper’s handle this evening. It is home to a grand gathering of galaxies, Coma Cluster, which is centered about 350 million light-years away.

As the Moon orbits Earth, the same hemisphere always faces our way. Over the course of its month-long cycle of phases, however, the Moon “wobbles” a bit, allowing us to see a total of 59 percent of the lunar surface.