Nova Cygni 1992
27.12.1995

In 1992 a tremendous explosion occurred in the constellation of Cygnus. Dubbed Nova Cygni 1992, this event most probably occurred in an accretion disk binary system. Astronomers hypothesize that this system's white dwarf had so much gas dumped onto it's surface that conditions became ripe for nuclear fusion.

M1: The Crab Nebula
25.07.1995

In the year 1054 a star in the constellation of Taurus exploded in a spectacular supernova so bright it appeared to dominate the sky except for the Sun and Moon for many days. It left behind one of the most brilliant nebulae, listed first in Charles Messier's list of nebulous sky objects.

NGC 6240: When Galaxies Collide
28.12.1995

Sometimes even galaxies can suffer a fatal attraction. Here gravity causes two galaxies to collide in a spectacular display of energetic gas, dust, and light. When galaxies collide it is rare that any stars in the galaxies themselves collide, or that any change will be seen in a human lifetime.

A Solar Prominence Unfurls
4.10.2008

On September 29, this magnificent eruptive solar prominence lifted away from the Sun's surface, unfurling into space over the course of several hours. Suspended in twisted magnetic fields, the hot plasma structure is many times the size of planet Earth and was captured in this view by the Sun-watching STEREO (Ahead) spacecraft.

Hydrogen Trifid
28.08.1998

Clouds of glowing hydrogen gas mingle with dark dust lanes in the Trifid Nebula, a star forming region in the constellation Sagittarius. In this and other similar emission nebulae, energetic ultraviolet light from an embedded hot young star strips electrons from the surrounding hydrogen atoms.

An Iridescent Cloud Over Colorado
25.11.2007

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.

When Rainbows Smile
11.03.2022

Want to see a rainbow smile? Look near the zenith (straight up) when the sun is low in the sky and you might. This example of an ice halo known as a circumzenithal arc was captured above a palm tree top from Ragusa, Sicily on February 24.

Breaking Distant Light
19.03.2002

In the distant universe, time appears to run slow. Since time-dilated light appears shifted toward the red end of the spectrum (redshifted), astronomers are able to use cosmological time-slowing to help measure vast distances in the universe.

Lynds Dark Nebula
20.09.2021

Stars are forming in Lynds Dark Nebula (LDN) 1251. About 1,000 light-years away and drifting above the plane of our Milky Way galaxy, the dusty molecular cloud is part of a complex of dark nebulae mapped toward the Cepheus flare region.

Lynds Dark Nebula 1251
30.09.2016

Stars are forming in Lynds Dark Nebula (LDN) 1251. About 1,000 light-years away, the dusty molecular cloud is part of a complex of dark nebulae mapped toward the Cepheus flare region, drifting above the plane of our Milky Way galaxy.