GRB 090423: The Farthest Explosion Yet Measured
29.04.2009

An explosion so powerful it was seen clear across the visible universe was recorded in gamma-radiation last week by NASA's orbiting Swift Observatory. Farther than any known galaxy, quasar, or optical supernova, the gamma-ray burst recorded last week was clocked at redshift 8.2, making it the farthest explosion of any type yet detected.

The Double Haze above Titan
10.08.2004

Most moons have no haze layer at all - why does Titan have two? Images from the Cassini spacecraft that slipped into orbit around Saturn last month confirm that the Solar System's most mysterious moon is surrounded not only by a thick atmosphere but also by two distinct spheres of haze.

A Year of New Perspectives
28.12.1999

Fittingly, 1999 saw a decade of astronomical discoveries to an end with portents of things to come - embodied in new spacecraft, telescopes, and perspectives to explore the distant Universe across the electromagnetic spectrum. X-ray astronomy in particular will likely flourish in coming

G21.5-0.9: A Supernova s Cosmic Shell
21.04.2005

The picture is lovely, but this pretty cosmic shell was produced by almost unbelievable violence - created when a star with nearly 20 times the mass of the sun blasted away its outer layers in a spectacular supernova explosion.

Galileo's Jupiter Probe
7.12.1995

Today, at about 5:00 pm EST, this 750 pound probe from NASA's robot spacecraft Galileo will plummet into Jupiter becoming the first probe to fly through the atmosphere of a gas giant planet.

Microquasar in Motion
16.09.2004

Microquasars, bizarre binary star systems, generating high-energy radiation and blasting out jets of particles at nearly the speed of light, live in our Milky Way galaxy. The energetic microquasar systems seem to consist...

Uranus' Largest Moon: Titania
4.03.1996

Titania's tortured terrain is a mix of valleys and craters. NASA's interplanetary robot spacecraft Voyager 2 passed this moon of Uranus in 1986 and took the above photograph. The photograph was then transmitted back to earth by radio.

Autumn and the Active Sun
23.09.1998

As the Sun heads South, crossing the celestial equator today at 1:37 a.m. Eastern Time, Autumn begins for Earth's Northern Hemisphere. This Autumnal Equinox finds an increasingly active Sun steadily approaching a solar cycle maximum expected around the year 2003.

3D Ahuna Mons
19.03.2016

Get out your red/blue glasses and gaze across Ceres at mysterious mountain Ahuna Mons. Shown in a 3D anaglyph perspective view, the mosaicked image data was captured in December of 2015, taken from the Dawn spacecraft's low-altitude mapping orbit about 385 kilometers above the surface of the dwarf planet.

APOD: 2025 September 26 Б A SWAN an ATLAS and Mars
26.09.2025

A new visitor to the inner Solar System, comet C/2025 R2 (SWAN) sports a long ion tail extending diagonally across this almost 7 degree wide telescopic field of view recorded on September 21.