EarthSky
Star map of Cassiopeia the Queen.

Close-up on Cassiopeia the Queen

The constellation Cassiopeia the Queen has the distinct shape of a W or M. Find her in the north-northeast sky on September and October evenings.

Comet in the sky above a lake, also reflecting in the lake.

What are comets?

Comets are loosely packed balls of ice and dust orbiting our sun, that sometimes become visible in Earth’s skies. A comet’s tail may stretch across millions of miles of space.

Illustration of Perseverance rover in space on Seotember 12, 2020.

Follow the Perseverance rover in real time on its way to Mars

Keep track of where NASA’s Mars 2020 Perseverance is on its journey through space toward its February 18, 2021, landing on Mars. This web app shows you where spacecraft is right now.

Various colored spheres with white text annotations on black background.

What are brown dwarfs?

A brown dwarf is more massive than a planet, but less massive than a star. Exactly how much more and less?

Sun halo with birds

Scientists call them 22-degree halos, because the shining ring around the sun (or moon) has a radius of approximately 22 degrees.

5 myths about lightning debunked

NOAA debunks some popular myths about lightning.

NASA’s guide to near light speed space travel

Take a couple of minutes and have a little fun with this new video from NASA

Star chart showing Venus, Sirius and Orion.

Venus, Orion and Sirius the Dog Star

A sign of the changing season, Sirius – the sky’s brightest star – is visible before sunup. You’ll know it’s Sirius if the very noticeable 3 stars in Orion’s Belt point to it.

Is it possible to hear meteors?

Can you hear a meteor as it streaks overhead? Some people have reported hearing meteors with a sizzling sound like bacon frying. Scientists now say you can, and explain how it happens.

Researchers track slowly splitting ‘dent’ in Earth’s magnetic field

A small but evolving dent in Earth’s magnetic field can cause big headaches for satellites.