Each Monday, I pick out North America’s celestial highlights for the week ahead (which also apply to mid-northern latitudes in the northern hemisphere). Check my main feed for more in-depth articles on stargazing, astronomy, eclipses and more.
The Night Sky This Week: September 9-15, 2024
This week’s stargazing highlights include Mercury near Regulus, the waxing gibbous moon near Antares in the southern sky, Venus shining near Spica, and the W-shaped constellation of Cassiopeia and the Big Dipper visible in the northern sky.
Here’s everything you need to know about the night sky this week:
Monday, September 9: Mercury And Regulus
Look to the east 30 minutes before sunrise this morning, and you’ll see the tiny planet Mercury—visible as a reddish dot—very close to Regulus, the brightest star in the constellation Leo, “the lion.” Regulus is one of the four bright stars often closely visited by the moon and planets because it’s aligned with the ecliptic—the solar system’s plane.
Tuesday, September 10: Moon And Antares
Tonight, the 47%-lit waxing gibbous moon will appear close to Antares, the brightest star in the constellation of Scorpius. Antares is a red supergiant star 12 times the sun’s mass, one of the biggest stars. Distinctly orangey-red to the observer (primarily through binoculars) and known as the “rival of Mars” because of its rosy color and because Mars passes it closely every 26 months. If you put it in the solar system, it would reach almost as far as where Jupiter orbits. Look to the southern sky anytime after sunset.
Wednesday, September 11: First Quarter Moon
Today is the first quarter moon, the phase of the moon’s orbit when it appears half-lit as seen from Earth. This is when the night skies get so brightly lit by moonlight in the early evenings that stargazing becomes more difficult. You should still stargaze, but don’t bother with faint constellations and don’t plan a stargazing trip to a dark sky this week (or next) because a full moon is coming—and that means a bright moon already in the sky as night falls.
Friday, September 13: Venus And Spica
Tonight, the magnitude -3.9 planet Venus will be just two degrees above magnitude -1 Spica, the brightest star in the constellation of Virgo and about 250 light-years distant. The two will be visible very close to the west-southwest horizon.
Saturday, September 14: Cassiopeia
Look to the north-northeast, and you’ll see the W-shaped constellation of Cassiopeia. Its five bright stars in a familiar shape are instantly recognizable. That’s handy because it’s a circumpolar constellation—it revolves around the north star—so it’s almost always in the northern hemisphere’s night sky.
Constellation Of The Week: Big Dipper
Look to the north-northwest and see the Big Dipper—also called the Plough—a pattern of seven bright stars. Alkaid will be at the top, at the tip of the handle, while Dubhe is at the lip of the bowl at the bottom. Like Cassiopeia, the Big Dipper is also circumpolar, so the two are always opposite in the northern night sky. They both revolve around Polaris, the North Star, once every 24 hours. The Big Dipper’s position low on the northern horizon after dark means it’s almost time for a change of seasons, as in the memory aid: “Spring up, fall down.”
The times and dates given apply to mid-northern latitudes. For the most accurate location-specific information, consult online planetariums like Stellarium and The Sky Live. Check planet-rise/planet-set, sunrise/sunset and moonrise/moonset times for where you are.
I’m an expert on the night sky and author of Stargazing in 2024, A Stargazing Program For Beginners, and When Is The Next Eclipse? For the very latest on sky events, please subscribe or check my main feed regularly for new articles.
Wishing you clear skies and wide eyes.