Astronomy Picture Of the Day (APOD)Accretion Disk Binary System
Our Sun is unusual in that it is alone - most stars occur in multiple or binary systems. In a binary system, the higher mass star will evolve faster and will eventually become a compact object - either a white dwarf star, a neutron star, or black hole.
During the 1968 Christmas season Frank Borman, James Lovell, and William Anders flew the Apollo 8 command module From the Earth to the Moon and back (launched Dec. 21, achieved 10 lunar orbits, landed Dec. 27).
Uranus' Moon Miranda
NASA's robot spacecraft Voyager 2 passed the planet Uranus and its moons in 1986. While the cloud tops of Uranus proved to be rather featureless, the surface of Miranda, the innermost of Uranus' large moons, showed several interesting features.
Prometheus, Pandora and Saturn's F Ring
The third and fourth innermost moons of Saturn were unexpectedly discovered to be gravitational "shepards." The inner moon Prometheus and the outer moon Pandora use their gravitational attraction to define Saturn's outermost ring.
Summer at the South Pole
December 22 marks the Winter Solstice - the beginning of winter in the Earth's northern hemisphere, and the first day of summer in the south! This view of Earth's southern hemisphere near the beginning of its summer was created using images from the Galileo spacecraft taken during the December 1990 flyby.
Hot Stars in the Trifid Nebula
In the center of the glowing red gas on the Trifid Nebula lies an open cluster of young hot stars. The energetic light from these stars strikes hydrogen atoms in the surrounding nebula causing them to lose their electrons.
A Galaxy Gravitational Lens
Sometimes it takes a keen eye to see a good mirage. Around the center of the red galaxy image in the above photograph lie four blue "smudges." Each smudge is actually a different image of the same background quasar. The central galaxy happens to fall directly in the light path of the quasar.
Albert Einstein: 1879 - 1955
Albert Einstein is considered by many the greatest astrophysicist. He is pictured here in the Swiss Patent Office where he did much of his great work. Einstein's many visionary scientific contributions include...
M51: The Whirlpool Galaxy
The Whirlpool Galaxy is frequently given as an example of a galaxy with classic spiral design. At only 15 million light years distant, M51, also cataloged as NGC 5194, is also one of the brighter and more picturesque galaxies on the sky.
The Space Shuttle Docks with Mir
Hundreds of kilometers above the Earth's surface, the United States Space Shuttle Atlantis docks with the Russian Space Station Mir. The photograph was taken by Nikolai Budarin from a Russian Soyuz spacecraft on July 4, 1995.