Astronomy Picture Of the Day (APOD)Dark Craters on Ganymede
Ganymede has craters within craters within craters. The old surface of the largest moon in the Solar System shows its age by the large amount of these impact features. The above picture released last...
Nearby Spiral M33
M33 is a prominent nearby spiral galaxy. Nicknamed the Triangulum, M33 is one of the larger members of the Local Group of Galaxies. Two massive spiral galaxies dominate the Local Group: M31 and our Milky Way Galaxy. M33 is the only other spiral galaxy known in the Local Group.
La Nina Watch
Goodbye El Niño. Hello La Niña? Scientists are watching to see if an evolving pool of relatively cool water in the mid-Pacific Ocean will develop into a full "La Niña". Over the past several months, the water temperature in the Equatorial Pacific Ocean has been doing a flip-flop.
Globular Cluster M3
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.
Rockets and Robert Goddard
Robert H. Goddard, one of the founding fathers of modern rocketry, was born in Worcester Massachusetts in 1882. As a 16 year old, Goddard read H.G. Wells' science fiction classic "War Of The Worlds" and dreamed of spaceflight. By 1926 he had designed, built, and launched the world's first liquid fuel rocket.
Hyakutake: Stars Through A Comet Tail
Comets are cosmic icebergs. They follow very elongated orbits which carry them from the frozen, remote outer reaches of the Solar System to close encounters with the Sun. Heated by sunlight, they slough off layers of material as gas and dust, forming their characteristic awe-inspiring comas (heads) and tails.
X Ray Triple Jet
Recorded on July 7, this animation using X-ray images of the Sun shows an amazing event - three nearly simultaneous jets connected with solar active regions. The two frames were taken several hours apart by the Soft X-ray Telescope on board the orbiting Yohkoh observatory.
Ghost Galaxy NGC 2915
How do you find a nearly invisible galaxy? Pictured above is the blue compact dwarf (BCD) galaxy NGC 2915. In visible light, shown above in yellow, this galaxy appears to be a normal dwarf galaxy, as indicated by the yellow smudge in the image center.
At Work on Mars
To learn about the history ofMars, just ask the rocks. Last year, that's exactly what the robot rover Sojourner did. Sojouner can be seen, above, analyzing a rock nicknamed Moe, trying to discern its past.
GRB 980703: A Reassuring Redshift
In the old days, just over a year ago, astronomers had little idea of the true distance to gamma-ray bursts. Did these enigmatic explosions occur in our outer Galaxy, or in the outer Universe?