Astronomy Picture Of the Day (APOD)Galactic Center Flicker Indicates Black Hole
Why would the center of our Galaxy flicker? Many astronomers believe the only credible answer involves a black hole. During observations of Sagittarius A* with the orbiting Chandra X-ray Observatory, the bright X-ray source at the very center of our Milky Way brightened dramatically for a few minutes.
NGC 3293: A Bright Young Open Cluster
Hot blue stars shine brightly in this beautiful, recently formed galactic or "open" star cluster. Open cluster NGC 3293 is located in the constellation Carina, lies at a distance of about 8000 light years, and has a particularly high abundance of these young bright stars.
Moon Occults Saturn
On September 18, 1997, many stargazers in the U. S. were able to watch a lovely early morning lunar occultation as a bright Moon passed in front of Saturn. Using a 1.2 meter reflector, astronomer Kris Stanek had an excellent view of this dream-like event from the Whipple Observatory atop Arizona's Mount Hopkins.
Moon AND Sun
Today's composite image was made from 22 separate pictures of the Moon and Sun all taken from Chisamba, Zambia during the total phase of the 2001 June 21 solar eclipse. The multiple exposures...
Moon AND Stars
Here's something you don't see too often ... a detailed picture of the full Moon surrounded by a rich field of background stars. It's true that bright moonlight scattered by the atmosphere...
3C175: Quasar Cannon
3C175 is not only a quasar, it is a galaxy-fueled particle cannon. Visible as the central dot is quasar 3C175, the active center of a galaxy so distant that the light we see from it was emitted when the Earth was just forming.
2dF Sees Waves of Galaxies
How are galaxies distributed in the universe? This question is of more than aesthetic interest because the answer likely holds clues to composition of the universe itself. The above map shows the distribution...
The Making of the Rotten Egg Nebula
Fast expanding gas clouds mark the end for a central star in the Rotten Egg Nebula. The once-normal star has run out of nuclear fuel, causing the central regions to contract into a white dwarf. Some of the liberated energy causes the outer envelope of the star to expand.
Deimos: A Small Martian Moon
Mars has two tiny moons, Phobos and Deimos. Pictured above is Deimos, the smaller moon of Mars. In fact, Deimos is one of the smallest known moons in the Solar System measuring only nine miles across.
Magnetars In The Sky
Indicated on this infrared image of the galactic center region are positions of candidate magnetars -- believed to be the strongest magnets in the galaxy. Classified by observers as Soft Gamma Repeaters (SGRs) and Anomalous X-ray Pulsars (AXPs), these cosmic powerhouses are likely city-sized, spinning, highly-magnetized neutron stars. How strong is a magnetar's magnetic field?