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September 2021 Moon Phases, Meteor Showers, Autumn Equinox, and More Astronomical Phenomena and Astronomy Calendar at WildHemlock.Com

Are you ready for fall? It’s coming in September 2021. I can’t wait to watch the leaves change colors and to dig my sweaters out of my closet. September 22nd is the first day of Astronomical Autumn, or the Autumn Equinox. September 1st is the first day of Meteorological Fall, while Labor Day on September 6th marks the unofficial end of Summer in the United States. The Autumn Equinox is defined as:

The intersection of the celestial equator and the sun’s ecliptic pathway in it’s southern descent towards the tropic of Capricorn. At this time, the Earth’s axial tilt is facing neither toward nor away from the sun, and there is approximately 12 hours of daylight and nighttime (at the equator).

The Celestial Sphere. Learn more about it and other astronomy facts at WildHemlock.Com! — The Celestial Sphere from the US Gov via Wikipedia

This sounds technical, but it only means that during the Earth’s uneven orbit, it is halfway between its high point and its low point. The sun is directly shining on the Equator, in the middle. During its high point, the Summer Solstice, the sun is most powerful on the Tropic of Cancer in the Northern Hemisphere. During its low point, the Winter Solstice, the sun’s most direct rays are on the Tropic of Capricorn in the Southern Hemisphere. During the Vernal (Spring) and Autumn (Fall) Equinoxes, the Equator experiences 12 hours of daylight and 12 hours of night time.

Meteorological Seasons, on the other hand, are based on the calendar. According to NOAA, meteorological seasons are the result of research into climate and weather history. September, October, and November have more similar weather patterns than September 22nd – December 21st. Additionally, these seasons better match our current calendar.

The closest Full Moon to the Autumn Equinox is known as the Harvest Moon. The Harvest Moon typically appears brighter, larger, and orange-tinted. The moon rises much quicker than usual, leading to a bright night that farm workers can utilize to continue the Harvest into the evening. According to EarthSky, this happens because the Moon has the lowest orbit of the year as viewed from the Earth. The atmosphere is thicker and more water saturated near the horizon, which causes the Moon to appear larger and red orange.

More Highlights for September 2021:

Autumn Equinox on September 22nd
Aurigids Meteor Shower on Sept 1st
Eta-Perdeids Meteor Shower on Sept 9th
Neptune at Opposition on Sept 14th
Harvest Moon on Sept 20th
Sextantids Meteor Shower on Sept 27th

And there’s plenty more! Check out the Glossary of Astronomical Events if you need any explanations.

Astronomical Seasons

Autumn Equinox - Learn More at WildHemlock.Com

Moon Phases

All times are in Eastern Standard Time (EST) or Eastern Daylight Savings Time (EDT).

Moon Facts

Moon. Learn more about lunar phenomena and moon phases at WildHemlock.Com

Perigee:	11th
Descending Node:	12th
Apogee:	26th
Ascending Node:	26th
Moon Name:	Harvest Moon, Corn Moon

Meteor Showers

Perseus Constellation thanks to Wikipedia. Learn More at WildHemlock.Com

Aurigids Meteor Shower

Radiant Point:	Auriga Constellation
Peak Date:	September 1st
Best Time, EST:	10 – 11 PM
Direction to Look:	North Northeast, low to the horizon
Learn More:	Sky At Night Magazine

Image from IAU and Sky & Telescope Magazine, via Wikipedia

ε-Perseids Meteor Shower