Astronomy Essentials
Are day and night equal at the equinox?
Are day and night equal at an equinox? No. Earth's atmosphere and our sun team up to give us more day than night at an equinox.
Astronomy Essentials
September equinox: All you need to know
The equinox is September 22. From around the world on the day of an equinox, the sun pretty much rises and sets due east and west.

SpaceX lasers define next era of Starlink technology

SpaceX lasers launched this week with a new batch of Starlink satellites marks a transition in tech for the satellite broadband network.
Astronomy Essentials

Harvest Moon 2021: All you need to know

In 2021, the Northern Hemisphere's Harvest Moon falls on September 20, or less than 2 days before the autumn equinox.

Rerun of a supernova blast expected 2037

Astronomers expect to see a rerun of a supernova blast, whose light traveled 10 billion years to reach us, in about the year 2037.

Moon, Saturn, Jupiter September 15 to 18

Watch for the moon, Saturn, Jupiter on September 15 to 18, 2021.

Impact on Jupiter surprises skywatchers

An impact on Jupiter has stargazers looking skyward to see if they can spot any lingering evidence of the September 13, 2021, event.

Missing impact debris mystery solved?

Where is the missing impact debris from the early solar system? A new study says it was probably vaporized into gas that subsequently escaped the solar system.
Brightest Stars

Alpha Cephei, a fast-spinning star

Alpha Cephei, in the constellation Cepheus the King, is a bit of an enigma. It’s spinning so fast that it appears like a slightly flattened beach ball.
Astronomy Essentials

Mercury greatest elongation September 14, best for S. Hemisphere

Watch for Mercury from Southern Hemisphere locations in late August, through September, 2021. Meanwhile, from northerly latitudes, bring binoculars!

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