Watch the Moon Travel Across a Giant Hexagon of Bright Stars This Week
It's a good reason to go out and look for constellations.
Over the next few nights, you can catch the moon traversing a hexagonal formation of stars high in the winter sky.
Six bright, easily identifiable stars in the winter sky form a beautifully shaped hexagon. Over the course of five nights, the moon will cross through the center of the winter hexagon or winter circle. The six stars that form its corners are part of the constellations Orion, Taurus, Auriga, Gemini, Canis Major, and Canis Minor. You'll be able to see the moon "cross" the shape from January 23 to January 27, with the moon sitting inside the hexagon on the middle three nights.
The six first magnitude stars include the recognizable blue of Sirius, sitting at the bottom of the formation; Rigel, at the foot of Orion; bright Aldebaran; Capella, high in the sky; Pollux, one of Gemini's heads; and Procyon in Canis Minor, per Sky & Telescope. This group is sometimes mentioned with the star Castor, the other head inside the constellation Gemini. Castor isn't a first magnitude star but is still quite bright. You can also spot the bright red star Betelgeuse in the middle of the hexagon, at Orion's shoulder.
You'll find the group relatively early in the evening, around 9:30 pm local time, according to Joe Rao at Space.com, if you look toward the south. They'll be up for quite a while. Though, this isn't a tight grouping, so they are spread out across the sky. EarthSky has a nice graphic of where the moon will appear relative to these six stars on each of the nights from January 23-27. You can also use an app like SkyView to track down the stars if you aren't sure where they're located.
Part of the fun of watching is seeing the movement of celestial bodies against one another, as the moon shifts its way through the large hexagon night after night, moving toward a full moon on January 27.
This movement has occurred three times this winter already, and, per Sky and Telescope, will happen three more times after this week's dance. You'll be able to see the moon cross the winter hexagon again on February 19-24, March 19-23, and April 15-19. Though, that's not to say it'll look the same every month. Plus, watching the moon move through the sky this week is great way to get a good sense of the bright winter stars if you're not already familiar with them.