Reflected Aurora Over Alaska
12.02.2013

Some auroras can only be seen with a camera. They are called subvisual and are too faint to be seen with the unaided eye. In the above image, the green aurora were easily visible to the eye, but the red aurora only became apparent after a 20-second camera exposure.

A Blue Bridge of Stars between Cluster Galaxies
15.07.2014

Why is there a blue bridge of stars across the center of this galaxy cluster? First and foremost the cluster, designated SDSS J1531+3414, contains many large yellow elliptical galaxies. The cluster's center...

Wright Mons in Color
15.01.2016

Informally named Wright Mons, a broad mountain about 150 kilometers across and 4 kilometers high with a wide, deep summit depression is featured in this inset image captured during the New Horizons flyby of Pluto in July 2015.

Horsehead: A Wider View
9.03.2018

Combined image data from the massive, ground-based VISTA telescope and the Hubble Space Telescope was used to create this wide perspective of the interstellar landscape surrounding the famous Horsehead Nebula. Captured at near-infrared wavelengths...

X-Ray Wind From NGC 3783
1.06.2000

A black hole is supposed to inexorably attract matter. But the intense radiation generated as material swirls and plunges into its high gravity field also heats up surrounding gas and drives it away.

Elements in the Aftermath
26.10.2001

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 like Hydrogen and Helium are combined to heavier elements like Carbon, Oxygen, etc. in a progression which ends with Iron.

Planets In The Sun
5.05.2000

Today, all five naked-eye planets (Mercury, Venus, Mars, Jupiter, Saturn) plus the Moon and the Sun will at least approximately line-up. As viewed from planet Earth, they will be clustered within about 26 degrees, the closest alignment for all these celestial bodies since February 1962, when there was a solar eclipse!

XMM-Newton First Light: X-Rays From The LMC
11.02.2000

Recently the European Space Agency released this and other spectacular "first light" pictures from its new orbiting x-ray observatory, christened XMM-Newton. A churning region of star birth and death in our small neighboring galaxy, the Large Magellanic Cloud (LMC), this field was one of several chosen to test out XMM-Newton's x-ray imaging capabilities.

IC 418: The Spirograph Nebula
11.04.2010

What is creating the strange texture of IC 418? Dubbed the Spirograph Nebula for its resemblance to drawings from a cyclical drawing tool, planetary nebula IC 418 shows patterns that are not well understood. Perhaps they are related to chaotic winds from the variable central star, which changes brightness unpredictably in just a few hours.

Galaxy NGC 474: Shells and Star Streams
5.01.2014

What's happening to galaxy NGC 474? The multiple layers of emission appear strangely complex and unexpected given the relatively featureless appearance of the elliptical galaxy in less deep images. The cause...