Arp 299: Black Holes in Colliding Galaxies
31.10.2016

Is only one black hole spewing high energy radiation -- or two? To help find out, astronomers trained NASA's Earth-orbiting NuSTAR and Chandra telescopes on Arp 299, the enigmatic colliding galaxies expelling the radiation.

NGC 7822: Cosmic Question Mark
12.10.2021

It may look like a huge cosmic question mark, but the big question really is how does the bright gas and dark dust tell this nebula's history of star formation. At the edge...

APOD: 2025 July 16 Б The Rosette Nebula from DECam
15.07.2025

Would the Rosette Nebula by any other name look as sweet? The bland New General Catalog designation of NGC 2237 doesn't appear to diminish the appearance of this flowery emission nebula, as captured by the Dark Energy Camera (DECam) on the Blanco 4-meter telescope at the NSF's Cerro Tololo Inter-American Observatory in Chile.

The Colliding Galaxies of NGC 520
12.09.2005

Is this one galaxy or two? The jumble of stars, gas, and dust that is NGC 520 is now thought to incorporate the remains of two separate galaxies. A combination of observations and simulations indicate the NGC 520 is actually the collision of two disk galaxies.

Jupiter and Saturn Pas de Deux
19.12.2001

Viewed from Earth, the solar system's planets do a cosmic dance that is hard to appreciate on any single night. But consider this well planned animated sequence combining 23 pictures taken at approximately 2 week intervals from June 2000 through May 2001.

Elements in the Aftermath
31.07.2019

Massive stars spend their brief lives furiously burning nuclear fuel. Through fusion at extreme temperatures and densities surrounding the stellar core, nuclei of light elements ike Hydrogen and Helium are combined to heavier elements like Carbon, Oxygen, etc. in a progression which ends with Iron.

APOD: 2024 December 8 Б Aurora around Saturns North Pole
7.12.2024

Are Saturn's auroras like Earth's? To help answer this question, the Hubble Space Telescope and the Cassini spacecraft monitored Saturn's North Pole simultaneously during Cassini's final orbits around the gas giant in September 2017. During this time, Saturn's tilt caused its North Pole to be clearly visible from Earth.

A Fox Fur, a Unicorn, and a Christmas Tree
6.04.2010

What do the following things have in common: a cone, the fur of a fox, and a Christmas tree? Answer: they all occur in the constellation of the unicorn (Monoceros). Pictured above...

HCG 87: A Small Group of Galaxies
6.07.2010

Sometimes galaxies form groups. For example, our own Milky Way Galaxy is part of the Local Group of Galaxies. Small, compact groups, like Hickson Compact Group 87 (HCG 87) shown above, are interesting partly because they slowly self-destruct.

Arp 188 and the Tadpole's Tail
10.12.2018

Why does this galaxy have such a long tail? In this stunning vista, based on image data from the Hubble Legacy Archive, distant galaxies form a dramatic backdrop for disrupted spiral galaxy Arp 188, the Tadpole Galaxy. The cosmic tadpole is a mere 420 million light-years distant toward the northern constellation of the Dragon (Draco).