Churning Clouds on Jupiter
11.08.2020

Where is Jupiter's ammonia? Gaseous ammonia was expected to be seen in Jupiter's upper atmosphere by the orbiting Juno spacecraft -- but in many clouds is almost absent. Recent Juno data, however, gives some clues: some high-level clouds appear to be home to an unexpected type of electrical discharge dubbed shallow lightning.

The Gamma Cygni Nebula
18.06.2022

Supergiant star Gamma Cygni is at the center of the Northern Cross. Near the plane of our Milky Way galaxy, that famous asterism flies high in northern summer night skies in the constellation Cygnus the Swan.

APOD: 2025 June 15 Б Two Worlds One Sun
15.06.2025

How different does sunset appear from Mars than from Earth? For comparison, two images of our common star were taken at sunset, one from Earth and one from Mars. These images were scaled to have the same angular width and are featured here side-by-side.

The Topography of Mars
28.06.2001

Mars has its ups and downs. Visible on the above interactive topographic map of the surface of Mars are giant volcanoes, deep valleys, impact craters, and terrain considered unusual and even mysterious. Particularly notable...

An Extreme UltraViolet View of the Comet
30.03.1996

As the Sun floods Comet Hyakutake with ultraviolet light gases in the coma scatter the radiation and fluoresce making the comet a bright source in the ultraviolet sky. The above image made using data...

The Vela Pulsar s Dynamic Jet
3.07.2003

The Vela pulsar is a neutron star born over 10,000 years ago in a massive supernova explosion. Above, false-color x-ray images from the Chandra Observatory reveal details of this remnant pulsar's x-ray bright nebula along with emission from a spectacular jet of high-energy particles.

A Note on the Perseus Cluster
12.09.2003

A truly enormous collection of thousands of galaxies, the Perseus Cluster - like other large galaxy clusters - is filled with hot, x-ray emitting gas. The x-ray hot gas (not the individual galaxies) appears in the left panel above, a false color image from the Chandra Observatory.

Crescent Rhea Occults Crescent Saturn
20.07.2008

Soft hues, partially lit orbs, a thin trace of the ring, and slight shadows highlight this understated view of the majestic surroundings of the giant planet Saturn. Looking nearly back toward the Sun, the robot Cassini spacecraft now orbiting Saturn captured crescent phases of Saturn and its moon Rhea in color a few years ago.

In the Shadow of Saturn
11.01.2009

In the shadow of Saturn, unexpected wonders appear. The robotic Cassini spacecraft now orbiting Saturn recently drifted in giant planet's shadow for about 12 hours and looked back toward the eclipsed Sun. Cassini saw a view unlike any other.

Hubble Remix: Active Galaxy NGC 1275
4.06.2010

Active galaxy NGC 1275 is the central, dominant member of the large and relatively nearby Perseus Cluster of Galaxies. Wild-looking at visible wavelengths, the active galaxy is also a prodigious source of x-rays and radio emission.