Iridescent Clouds from the Top of the World Highway
7.02.2011

Why would a cloud appear to be different colors? A relatively rare phenomenon known as iridescent clouds can show unusual colors vividly or a whole spectrum of colors simultaneously. These clouds are formed of small water droplets of nearly uniform size.

Sunrise Solstice over Stonehenge
19.06.2021

Today the Sun reaches its northernmost point in planet Earth's sky. Called a solstice, many cultures mark this date as a change of seasons -- from spring to summer in Earth's Northern Hemisphere and from fall to winter in Earth's Southern Hemisphere.

APOD: 2024 July 7 Б Iridescent Clouds over Sweden
6.07.2024

Why are these clouds multi-colored? A relatively rare phenomenon in clouds known as iridescence can bring up unusual colors vividly -- or even a whole spectrum of colors simultaneously. These polar stratospheric clouds also, known as nacreous and mother-of-pearl clouds, are formed of small water droplets of nearly uniform size.

APOD: 2025 July 7 Б Interstellar Comet 3I ATLAS
6.07.2025

It came from outer space. An object from outside our Solar System is now passing through at high speed. Classified as a comet because of its gaseous coma, 3I/ATLAS is only the third identified macroscopic object as being so alien.

COBE Dipole: Speeding Through the Universe
4.02.1996

Our Earth is not at rest. The Earth moves around the Sun. The Sun orbits the center of the Milky Way Galaxy. The Milky Way Galaxy orbits in the Local Group. The Local Group falls toward the Virgo Cluster of Galaxies.

Comet PanSTARRs and the Galaxies
5.06.2020

Comet PanSTARRs, C/2017 T2, shared this stunning telescopic field of view with galaxies M81 and M82 on May 22/23. Of course, the galaxies were some 12 million light-years distant and the comet about 14 light-minutes away, seen in planet Earth's sky toward the Big Dipper.

Find the New Moon
24.07.2022

Can you find the Moon? This usually simple task can be quite difficult. Even though the Moon is above your horizon half of the time, its phase can be anything from crescent to full.

Free Floating Planets In Orion
31.03.2000

This false-colour image of the young Trapezium star cluster in the Orion Nebula was made with an infrared camera at wavelengths about twice as long as visible light. The infrared data are part...

Eclipse in the Mist
4.06.2003

The Sun and Moon rose together over much of Europe on the morning of May 31st with the first solar eclipse of 2003 already in progress. And while sightings of the full annular phase...

Betelgeuse, Betelgeuse, Betelgeuse
15.02.1997

Betelgeuse (sounds a lot like "beetle juice"), a red supergiant star about 600 light years distant, is seen in this Hubble Space Telescope image -- the first direct picture of the surface of a star other than the Sun. A bright, as yet unexplained hotspot is revealed on its surface!