Top September astronomy events to mark on your calendar
As the calendar turns to September, the leaves on trees across the northern tier of the United States start to turn a tinge of yellow, orange and brown, a taste of what's to come this fall in forests across the country. However, for stargazers September marks the return of longer nights with a slate of astronomical events unfolding in the early autumn sky.
Not only will nights become longer than days across the Northern Hemisphere in September, but the weather will also help to bring the night sky into focus. The gradual downturn in humidity results in crisper views of the night sky, a stark difference from the muggy summer nights that can make some stars look slightly fuzzy.
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The Milky Way glows over a mountain and colorful trees. (Erike Fusiki) |
From great views of the largest planet in the solar system to one of the most popular full moons of the year, here are the top astronomy events to mark on your calendar in September:
The second weekend of September will kick off with an astronomical alignment featuring one of the year's most popular full moons.
Every full moon has several nicknames that relate to events that take place during the time of year that they rise, sometimes dating back to the time of early Colonials settling in America. September's full moon is no exception -- it's known as the Harvest Moon because it usually rises when summer crops are ready to be harvested. This nickname can be traced back to a time before electricity when farmers used the moonlight to continue harvesting crops well past sunset.
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Under a nearly full moon, Larry McMillan drives a tractor during wheat harvest, Monday, Aug. 24, 2010, on his farmland near Moscow, Idaho. (AP Photo/Ted S. Warren) |
Other names for September's full moon include the Corn Moon, Falling Leaves Moon, Rutting Moon, Leaves Turning Moon, according to the Old Farmer's Almanac.
The Harvest Moon will rise on Friday, Sept. 9, glowing into the early hours of Saturday, Sept. 10, and it will not be alone in the sky.
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Image not to scale. The rings of Saturn cannot be seen without a telescope. (AccuWeather) |
The full moon will appear directly between Saturn and Jupiter throughout the entire night in the southern sky. The following night, the moon will shift away from Saturn and will appear extremely close to Jupiter.
The new month will signal the changing of the seasons around the world, although the start of autumn will come a few weeks early for meteorologists.
The September equinox is traditionally the official start of astronomical autumn across the Northern Hemisphere and astronomical spring across the Southern Hemisphere. This date varies from year to year due to the Earth's imperfect orbit around the sun, and this year, the equinox takes place Thursday, Sept. 22, at 9:03 p.m. EDT.
At that point, the sun's most direct rays will be pointed at the equator, resulting in around 12 hours of daylight and 12 hours of nighttime everywhere around the globe.
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A satellite image captured by NOAA's GOES-16 weather satellite shows what Earth looked like on the March equinox in 2019. (NOAA) |
However, due to the inconsistencies in the start and end dates of astronomical seasons, meteorologists follow the calendar rather than the orbit of the Earth around the sun to determine the seasons.
Meteorological autumn officially begins on Sept. 1 and concludes on Nov. 30 every year. This method is not only more consistent, but it makes it easier for forecasters to compare seasonal statistics from one year to another.
Skywatchers who step outside early in the month to see the moon appear next to Jupiter may take notice of how bright the planet shines in the sky. Jupiter will continue to shine brighter and brighter heading into the final week of the month as it reaches opposition.
Opposition is a term astronomers use when a planet appears exactly opposite of the sun from the perspective of the Earth. This will also be around the same time that Jupiter is closest to the Earth, making it appear brighter than any other time of the year.
Although the Jupiter opposition takes place on Sept. 26, any cloud-free night during the second half of the month and into the start of October will be a good opportunity for viewing the planet.
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Jupiter is one of the best planets to view with a telescope, not only because it is very easy to find, but also because of its features.
Most basic telescopes have enough magnification power to reveal the four largest moons orbiting the planet: Europa, Ganymede, Io, and Callisto. More powerful telescopes can reveal more details about the planet itself, including its colorful cloud bands and even its Big Red Spot, a massive storm churning on the planet.
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Jupiter and its four largest moons were photographed by NASA's Juno spacecraft on its approach to the planet in 2016. A similar sight can be seen from Earth with the help of a telescope. (NASA/JPL) |
Folks who set up a telescope to observe Jupiter should also consider pointing it at Saturn, which will appear to the right of Jupiter. Although Saturn does not shine quite as bright, a telescope can reveal the planet's famous rings, one of the most breathtaking features in the entire solar system.
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