Fact checked by Haley Mast

From a close encounter with Jupiter to welcoming fall, this month is all about change.

Dust off that sweatshirt, grab a blanket, and enjoy the waning weeks of summer while you're looking up into the evening sky. Below are just some of the beautiful celestial highlights to look forward to in September 2022. 

Catch a View of the Harvest Moon (Sept. 9) 

September’s full moon, nicknamed the "Harvest Moon", reaches peak fullness on September 9 at 5:58 a.m. EDT, but will remain a spectacle in the days just before and after that date.

As its name implies, this full moon is so-called due to its timing (rising for several days just after sunset) in providing crucial light to farmers harvesting their crops. Unlike other full moons, the naming of this one is tied specifically to the fall equinox. As such, the Harvest Moon can sometimes occur in early October (as it did in 2020). When that happens, September’s full moon is appropriately called the "Corn Moon."

Neptune at Its Closest (And Brightest) to Earth (Sept. 16)

Neptune, the eighth and farthest known planet in our solar system (sorry, Pluto!), will reach its annual opposition—when the Earth passes between it and the sun—on September 16. Despite having a mass 17 times that of Earth, this gas giant is so far away (it takes light four hours to travel between Neptune and Earth during opposition) that it appears very dim even at its closest. To view it, Earth-Sky recommends consulting this chart from TheSkyLive and investing in a tripod-mounted pair of binoculars or a telescope. 

Fun fact: Neptune's winds can reach speeds up to 1,500 miles per hour—the fastest yet detected in our solar system.1 It’s also our coldest planet, dipping down to temperatures of -373 degrees Fahrenheit.2 Have your stargazing guests ponder that while you attempt to locate this blue-tinged wonder.

Wave Goodbye to Summer and Greet the Fall Equinox (Sept. 22) 

The first day of autumn in the Northern Hemisphere will officially arrive on this day, and for our friends in the Southern Hemisphere, it's the first day of spring. At 9:03 p.m. EDT, we'll say goodbye to the lazy days of summer and welcome the start of fall with the autumnal equinox. According to Time and Date, this event marks "the moment the sun crosses the celestial equator—the imaginary line in the sky above the Earth’s equator—from north to south and vice versa in March."

In anticipation of the colder months ahead, the fall equinox offers an important reminder to start thinking about firewood, pumpkins, and dusting off your warmer clothing. According to the Farmers' Almanac’s long-range forecast—which, like any long-range weather forecast, should be taken with a grain of salt—the coming winter could have “the coldest outbreaks of arctic air we have seen in several years.”

September’s Late New Moon Gives Way to Dark Skies (Sept. 25)

Comets kick up dust in Helix Nebula.

September’s new moon will arrive on September 25, with the lunar surface illuminated by the sun facing away from Earth. This phenomenon will give way to exceptionally dark skies devoid of moonlight and perfect for observing galaxies, planets, and other celestial wonders.

Need a target? This month, we’re recommending the Helix Nebula (NGC 7293) or, as it’s more widely known, the "Eye of God." Located roughly 650 light-years from Earth, it’s one of the closest planetary nebulae and easy to spot through binoculars or small telescopes. It’s believed to have formed about 10,600 years ago when a dying star exploded and shed its outer layers into space. To spot it, the site Cosmic Pursuits recommends looking "10ºNW of the bright star Fomalhaut." Check their star chart here and good luck!

Watch NASA Crash a Spacecraft Into an Asteroid (Sept. 26) 

In an effort to better understand the methods that could one day help us deflect a celestial body on a collision course with Earth, NASA on September 26 will fly its Double Asteroid Redirection Test (DART) spacecraft directly into the path of an asteroid named Dimorphos. This half-mile-wide asteroid, about 6.7 million miles from Earth, orbits a much larger asteroid named Didymos. NASA is eager to discover how the impact changes orbital relations between the two—valuable data that could one day help us design larger asteroid-deflecting spacecraft.

Coverage of the event will begin live at 6 p.m. EDT on September 26, 2022, on NASA’s website. DART is expected to make its violent encounter with Dimorphos at approximately 7:15 p.m. EDT.

Jupiter Makes Its Closest Approach in 70 Years (Sept. 26)

On September 26, Jupiter will be at its closest and brightest in nearly a century. Called opposition, this annual celestial phenomenon occurs when Earth’s faster orbit places it directly between a planet and the sun. At "only" a little over 367 million miles from Earth, this will be the closest Jupiter has come in 70 years and the best we’ll get for the rest of the 21st century. Get out those telescopes and binoculars!

To spot the great gas giant, its colorful atmosphere, and even some of its 79 moons, look to the east just after sunset. It will be 18 times brighter than its close neighbor Saturn. And if you miss it on the 26th, no worries—Jupiter will be just as close and bright nearly all of September and into October.

Welcome Back the Haunting Zodiacal Light (late Sept.)

This celestial object (aka the Zodiacal light) also signals the start of fall for the Northern Hemisphere. It's described as a "cone-shaped glow," similar to the Milky Way's dusty look, but made out of comet and asteroid dust. It’s estimated that for this phenomenon to remain a steady presence in our skies, some three billion tons of matter must be injected into it each year by comets. For best viewing, look up your local sunrise time and subtract an hour—and make plenty of coffee to keep you awake as this "false dawn" appears.