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 16-22, 2024
From the “Super Harvest Moon Eclipse” to a conjunction of Venus and bright star Spica to a panorama of the moon, Jupiter and the Pleiades, there are many reasons to look up at night as the equinox comes to planet Earth.
Here’s everything you need to know about the night sky this week:
Tuesday, September 17: ‘Super Harvest Moon Eclipse’ And Saturn
Probably the most famous full moon of the year is the “Harvest Moon” because its light helps farm workers gather crops late into the night. This one is a bit different. As well as appearing close to Saturn, it will appear slightly larger and brighter in the night sky—thanks to its “supermoon” status—and will move through Earth’s outer shadow in space. The result will be a slight partial lunar eclipse on the night side of Earth, including North and South America, Europe, Africa, and the Middle East.
The best time to see the full moon will be moonrise where you are, though exactly when the partial lunar eclipse will become visible will depend on your location; a celestial schedule is available from Timeanddate. The time to watch an 8.4% slither of the moon draped in shadow will be between 10:12-11:15 p.m. EDT.
Tuesday, September 17: Venus And Spica
While you watch the “Super Harvest Moon” rise in the east, don’t forget to swivel 180 degrees to watch Venus tangle with a bright star. The magnitude -3.9 planet 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.
Wednesday, September 18: Neptune At Opposition
Neptune is tonight the biggest, brightest and best placed it gets during 2024. A planet’s opposition occurs when Earth passes between it and the sun, which must happen each Earth year as our planet’s 365-day orbit causes it to undertake Neptune on the inside. The eighth planet from the sun will be well-positioned and shining brightly for the next few weeks against the background stars of Pisces, “the fish,” in the eastern sky close to Saturn. At magnitude +7.8, Neptune is outside naked eye visibility—you’ll need any telescope to see it and a large telescope to appreciate it.
Sunday, September 22: Moon, Jupiter And The Pleiades
Look east-northeast around midnight wherever you are, and you’ll see a 67%-lit waning gibbous moon sandwiched by Jupiter below and the Pleiades (pronounced “plee-er-deez”) above.
Sunday, September 22: Equinox
At 8:43 a.m. EDT today (12.44 p.m. UTC), it’s the moment equinox, which marks the precise time when the midday sun crosses the equator somewhere on Earth. Equinoxes occur twice per year, in late March and late September. They’re global events co-occurring for everyone on the planet. This “southward equinox”—known in the northern hemisphere as the fall or autumnal equinox—is an important “quarter day” in the Earth’s journey around the sun, signaling the end of summer and the beginning of astronomical autumn. It’s a consequence of Earth rotating on a tilted axis, which means different parts of the planet are orientated towards the sun at different parts of its annual orbit.
Object Of The Week: The ‘Seven Sisters’ Stars
The Pleiades is an open cluster of stars, also known as the “Seven Sisters,” rising in the east as night falls this month. It’s in the constellation Taurus and can easily be seen with the naked eye as a small, bright cluster. The Pleiades contains seven main bright stars—Alcyone, Atlas, Electra, Maia, Merope, Taygeta and Pleione—all 444 light-years distant and about 100 million years old, which is young compared to most stars.
Look directly at the Pleiades, and you’ll see points of light in the shape of a mini-Big Dipper. However, look slightly to one side, and you’ll see a glowing misty patch in the corner of your eyes, unlike anything else in the night sky. That beautiful sight results from the collective brightness of about 800 young blue stars.
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.
