Astronomy Picture Of the Day (APOD)ASCA X-Ray Observatory
Today marks the third anniversary of the launch of the Advanced Satellite for Cosmology and Astrophysics (ASCA; renamed from Astro D when launched). ASCA, seen here superposed on galaxy M31, is a Japanese satellite for which NASA has provided some scientific equipment. ASCA carries four large-area X-ray telescopes.
Periodic Comet Swift-Tuttle
Comet Swift-Tuttle, shown above in false color, is the largest object known to make repeated passes near the Earth. It is also one of the oldest known periodic comets with sightings spanning two millennia.
Abell 3627 in the Great Attractor
Are these galaxies near the center of the largest gravitationally bound concentration of mass yet known? Previously, the cluster of galaxies known as Abell 3627 was largely unstudied because dust in the disk of our own Galaxy obscured much of its light.
Edwin Hubble Discovers the Universe
No person in history has had greater impact in determining the extent of our universe than Edwin Hubble. From proving that other galaxies existed to proving that galaxies move apart from one another, Hubble's work defined our place in the cosmos.
The Early Universe
What did our universe look like when it was young? To answer this, cosmologists run sophisticated computer programs tracking the locations of millions of particles. The above animated frame is the result of such a calculation and shows how our universe might have looked when it was just a fracton of its current age.
NEAR to an Asteroid
Excitement mounts as NASA's Near Earth Asteroid Rendezvous (NEAR) spacecraft nears launch - currently scheduled for 3:53 ET on February 16. NEAR's mission is to become the first spacecraft to rendezvous with and orbit an asteroid, the asteroid designated 433 Eros.
NGC 2237: The Rosette Nebula
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 the this flowery emission nebula. Inside the nebula lies an open cluster of bright young stars designated NGC 2244.
7,000 Stars And The Milky Way
This panorama view of the sky is really a drawing. It was made in the 1940s under the supervision of astronomer Knut Lundmark at the Lund Observatory in Sweden. To create the picture, draftsmen...
Pluto Not Yet Explored
Cold, distant, Pluto is the only planet in our Solar System which has not been visited by a spacecraft from Earth. The story goes that the legend "Pluto Not Yet Explored" on a US postal stamp depicting the tiny, mysterious world inspired a JPL employee to develop plans for a Pluto flyby.
Sputnik: The Traveling Companion
Sputnik means "traveling companion". In stark contrast to this innocent sounding name, the launch of the Earth's first "artificial moon", Sputnik 1, by the Soviets on October 4, 1957 shocked the free world, setting in motion events which resulted in the creation of NASA and the race to the Moon.