Astronomy Picture Of the Day (APOD)The Swirling Center of NGC 4261
What evil lurks in the hearts of galaxies? The above picture by the Hubble Space Telescope of the center of the nearby galaxy NGC 4261 tells us one dramatic tale. Here gas and dust are seen swirling near this elliptical galaxy's center into what is almost certainly a massive black hole.
GL 229B: An Elusive Brown Dwarf?
What type of matter makes up most of the universe? This question is arguably the most perplexing astronomical mystery of our time. A leading candidate is a type of dim, low mass star called a "brown dwarf" star.
An X-ray Hot Supernova in M81
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).
In May of 1993, the Space Shuttle Columbia orbited the Earth carrying the Spacelab Deutsche 2 (SL-D
51 Pegasi: A New Planet Discovered
Are we alone in the universe? Do other stars have planets too? Humanity took one step closer to answering these questions in October 1995 when it was announced that the star 51 Pegasi harbors at least one planet.
NGC 2440 Nucleus: The Hottest Star?
In the center of the above photograph lies a star with one of the hottest surface temperatures yet confirmed. This bright white dwarf star's surface has been measured at greater than 200,000 degrees Celsius - more than 30 times hotter than that of our own Sun.
Named for Nobel laureate physicist Arthur Holly Compton, the Compton Gamma Ray Observatory (CGRO) Satellite was launched in April of 1991 aboard the Space Shuttle Atlantis. CGRO's mission is to explore the Universe at gamma-ray energies.
Shadow at the Lunar South Pole
In 1994, the space probe Clementine spent 70 days in lunar orbit mapping the Moon's surface. Shown above is a dramatically detailed composite view centered on the Moon's South Pole constructed from 1500 Clementine images.
Too Close to a Black Hole
What would you see if you went right up to a black hole? Above are two computer generated pictures highlighting how strange things would look. On the left is a normal star field containing the constellation Orion. Notice the three stars of nearly equal brightness that make up Orion's Belt.
A Star Where Photons Orbit
The above computer animated picture depicts how a very compact star would look to a nearby observer. The star pictured is actually more compact that any known except a black hole, so it is only hypothetical. The observer is situated at the photon sphere, where photons can orbit in a circle.