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Cassiopeia the Queen ascends in September

Cassiopeia the Queen is an easy-to-find constellation. It has the shape of a W or M. Look in the north-northeast sky on September and October evenings.

Here are the 2022 Breakthrough Prize winners

2022 Breakthrough Prize winners made discoveries leading to Covid-19 vaccines, treatments for neurological diseases, and more precise quantum clocks.

September birthstone is the sapphire

Sapphire, the September birthstone, is typically blue, the color caused by small amounts of titanium and iron in the crystal structure.

Was Comet ATLAS a blast from the past?

Comet ATLAS was seen to break apart in 2020, while still relatively far from the sun. An astronomer thinks our early ancestors saw this comet.

Pluto became a dwarf planet on today’s date

Pluto is the largest of many small bodies in the outer solar system. That's partly why it was demoted from major planet to dwarf planet in 2006.

Voyager 2 confirms Neptune’s rings this date in 1989

NASA's Voyager 2 confirmed the discovery of Neptune's rings on August 22, 1989, when it took images of a faint, continuous ring system around the planet.

Observing meteors: Top 10 tips for the Perseids

The 2021 Perseid meteor shower is rising to its peak and many are observing meteors. Here are our best 10 tips for watching this shower, or any other!

2021 moon phases, with distances from Earth

2021 moon phases in a chart format. Dates closest to new moon provide the darkest skies and the best opportunities for stargazing and meteor-watching.

Mares’ tails over the Pacific Northwest

Mares' tails - aka cirrus uncinus clouds - are found high above Earth's surface, where the air is very cold. They might mean rain is on the way.

Why and how fireflies light up

A firefly's familiar glow is caused by a chemical reaction. Why and how fireflies light up here, plus many wonderful firefly photos.

2021 EarthSky Fundraiser

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