The Matter of the Bullet Cluster
15.01.2017

What's the matter with the Bullet Cluster? This massive cluster of galaxies (1E 0657-558) creates gravitational lens distortions of background galaxies in a way that has been interpreted as strong evidence for the leading theory: that dark matter exists within.

The Eskimo Nebula from Hubble and Chandra
30.07.2013

In 1787, astronomer William Herschel discovered the Eskimo Nebula. From the ground, NGC 2392 resembles a person's head surrounded by a parka hood. In 2000, the Hubble Space Telescope imaged the Eskimo Nebula in visible light, while the nebula was imaged in X-rays by the Chandra X-ray Observatory in 2007.

Great Observatories Explore Galactic Center
11.11.2009

Where can a telescope take you? Four hundred years ago, a telescope took Galileo to the Moon to discover craters, to Saturn to discover rings, to Jupiter to discover moons, to Venus to discover phases, and to the Sun to discover spots.

The Nebula And The Neutron Star
1.02.2003

The lonely RX J1856.5-3754 was formed from the collapsed core of an exploding star. At a distance of 180 light-years it is the closest known neutron star. More massive than...

APOD: 2026 March 6 Б The Astrosphere of HD 61005
6.03.2026

Do young stars blow bubbles? The larger view shows a stellar field observed with the Cerro Tololo Inter-American Observatory in Chile, and the inset highlights HD 61005, a star like our Sun, only 120 light-years away.

A 2017 U1: An Interstellar Visitor
3.11.2017

Traveling at high velocity along an extreme hyperbolic orbit and making a hairpin turn as it swung past the Sun, the now designated A/2017 U1 is the first known small body from interstellar space.

APOD: 2024 March 25 Б Sonified: The Jellyfish Nebula Supernova Remnant
25.03.2024

What does a supernova remnant sound like? Although sound is a compression wave in matter and does not carry into empty space, interpretive sound can help listeners appreciate and understand a visual image of a supernova remnant in a new way. Recently, the Jellyfish Nebula (IC 443) has been sonified quite creatively.

X rays From HCG 62
9.03.2001

Scanning the skies for galaxies Canadian astronomer Paul Hickson and colleagues identified some 100 compact groups of galaxies, now appropriately called Hickson Compact Groups (HCGs). With only a few member galaxies per group, HCGs...

APOD: 2026 May 21 Б A Collision of Galaxy Clusters
21.05.2026

This big beautiful spiral shines in X-ray light. It is about 20 times larger than our Galaxy. It belongs to Abell 2029, a galaxy cluster one billion light-years away. (To see only the galaxies...

Forty Thousand Meteor Origins Across the Sky
11.05.2009

Where do meteors come from? Visible meteors are typically sand-sized grains of ice and rock that once fragmented from comets. Many a meteor shower has been associated with a known comet, although some intriguing orphan showers do remain.