Shadow Cone of a Total Solar Eclipse
6.01.2003

Sometimes, during a total eclipse of the Sun, a strange shadow of darkness can be seen stretching off into the distance. Called a shadow cone, they are visible because the Earth's atmosphere is not completely transparent, scattering sunlight and hence appearing blue during the day.

A Blue Moon Halo over Antarctica
11.08.2015

Have you ever seen a halo around the Moon? Such 22 degree rings around the Moon -- caused by ice crystals falling in the Earth's atmosphere -- are somewhat rare. OK, but have you ever seen a blue moon?

Astro 1 In Orbit
4.05.1996

In December of 1990, the Space Shuttle Columbia carried an array of astronomical telescopes high above the Earth's obscuring atmosphere to observe the Universe at ultraviolet and x-ray wavelengths. The telescopes, known...

APOD: 2025 July 23 Б Fireball over Cape San Blas
23.07.2025

Have you ever seen a fireball? In astronomy, a fireball is a very bright meteor -- one at least as bright as Venus and possibly brighter than even a full Moon. Fireballs are rare -- if you see one you are likely to remember it for your whole life.

The Dancing Auroras of Saturn
27.06.2021

What drives auroras on Saturn? To help find out, scientists have sorted through hundreds of infrared images of Saturn taken by the Cassini spacecraft for other purposes, trying to find enough aurora images to correlate changes and make movies.

A Sharp View of the Sun
18.09.2011

Here is one of the sharper views of the Sun ever taken. This stunning image shows remarkable details of a dark sunspot across the image bottom and numerous boiling granules which appear like kernels of corn across the top.

Return at Sunrise
13.03.2015

Thursday, shortly after local sunrise over central Asia, this Soyuz spacecraft floated over a sea of golden clouds during its descent by parachute through planet Earth's dense atmosphere. On board were Expedition 42 commander Barry Wilmore of NASA and Alexander Samokutyaev and Elena Serova of the Russian Federal Space Agency (Roscosmos).

Astro 1 In Orbit
3.12.2005

Fifteen years ago, in December of 1990, the Space Shuttle Orbiter Columbia carried an array of astronomical telescopes high above the Earth's obscuring atmosphere to explore the Universe at ultraviolet and x-ray wavelengths.

A Green Flash from the Sun
9.09.1997

Many think it is just a myth. Others think it is true but its cause isn't known. Adventurers pride themselves on having seen it. It's a green flash from the Sun. The truth is the green flash does exist and its cause is well understood.

When Venus Rises with the Sun
8.06.2012

This dramatic telephoto view across the Black Sea on June 6 finds Venus rising with the Sun, the planet in silhouette against a ruddy and ragged solar disk. Of course, the reddened light...