The Sun Oscillates
15.06.1999

Our Sun is in a continual state of oscillation. Large patches of the Sun vibrate in and out, back and forth, even as the Sun rotates. One mode of Solar oscillation is depicted graphically above, with blue indicating outward motion, and red indicating inward motion.

The Mileage of Light
28.05.2011

If you're driving down a dark road on a starry night, you might want to check the odometer. Earlier this month, when traveling astronomer Dennis Mammana did he was greeted with the significant mileage reading of 186,282 miles. That's the number of miles light travels in one second.

An X-ray Hot Supernova in M81
3.12.1995

In 1993, a star in the galaxy M81 exploded. Above is a picture of the hot material ejected by this supernova explosion. The picture was taken in X-rays with the Advanced Satellite for Cosmology and Astrophysics (ASCA).

Globular Cluster M3
6.12.1996

This huge ball of stars predates our Sun. Long before mankind evolved, before dinosaurs roamed, and even before our Earth existed, ancient globs of stars condensed and orbited a young Milky Way Galaxy.

X-Raying the Moon
31.08.1995

Above is a picture of the Moon taken in X-rays by the Roentgen Observatory Satellite ROSAT in 1990. This famous picture shows three distinct regions: a bright X-ray sky, a bright part of the Moon, and a relatively dark part of the Moon.

Moon Over Haleakala
10.06.2006

A waxing crescent Moon shines over the caldera of dormant volcano Haleakala and observatory domes in this dramatic view from above the clouds. Looking west from Maui, Hawaii on May 31st, the scene also records the lights of Honolulu on the horizon.

Median Mashup: Hubble s Top 100
13.09.2014

Now, as you sip your cosmic latte you can view 100 Hubble Space Telescope images at the same time. The popular scenes of the cosmos as captured from low Earth orbit are all combined into this single digital presentation. To make it, Hubble's top 100 images were downloaded and resized to identical pixel dimensions.

La Silla Eclipse Sequence
5.07.2019

The road to the high mountaintop La Silla Observatory in the Chilean Atacama Desert also led in to the path of July 2nd's total solar eclipse. Recorded at regular intervals before and after...

Good Morning Moon
12.01.2024

Yesterday, the Moon was New. But on January 9, early morning risers around planet Earth were treated to the sight of an old Moon, low in the east as the sky grew bright before dawn.

Comet Hyakutake Passes the Sun
16.05.1996

On May 1, Comet Hyakutake made its closest approach to the Sun. During this time it was not possible to view the comet with most astronomical instruments because of the brightness of the nearby Sun.