Astronomy Picture Of the Day (APOD)HH111's 12 Light-Year Star Jet
The complex interactions of three stars in the Orion B molecular cloud complex have resulted in the ejection of particles along a 12 light-year long jet. One of the stars in the HH111 system has apparently also been ejected leaving two stars tightly bound in a binary orbit.
Mercury on the Horizon
Have you ever seen the planet Mercury? Because Mercury orbits so close to the Sun, it is never seen far from the Sun, and so is only visible near sunrise or sunset. If trailing the Sun, Mercury will be visible for several minutes before it follows the Sun behind the Earth.
Apollo 16: Exploring Plum Crater
Apollo 16 spent three days on Earth's Moon in April 1972. The fifth lunar landing mission out of six, Apollo 16 was famous for deploying and using an ultraviolet telescope as the first lunar observatory, and for collecting rocks and data on the mysterious lunar highlands. In the above picture, astronaut John W.
A Wind From The Sun
A wind from the Sun blows through our Solar System. The behaviour of comet tails as they flapped and waved in this interplanetary breeze gave astronomers the first hint of its existence. Streaming outward at 250-400 miles/second, electrons and ions boiling off the Sun's incredibly hot
Martian Dust Devil Trails
Who's been marking up Mars? This portion of a recent high-resolution picture from the orbiting Mars Global Surveyor spacecraft shows twisting dark trails criss-crossing a relatively flat rippled region about 3 kilometers wide on the martian surface.
NEAR Shoemaker Views Eros
Orbiting asteroid 433 Eros, 145 million miles from Earth, NASA's NEAR spacecraft has been returning stunning views as its year long mission of exploration gets underway. A mosaic of recent NEAR images recorded...
Weak Lensing Distorts the Universe
Is the distant universe really what it appears to be? Astronomers hope not. Intervening dark matter, which is normally invisible, might show its presence by distorting images originating in the distant universe, much the way an old window distorts images originating on the other side.
A GRB 000301C Symphony
Telescopic instruments in Earth and space are still tracking a tremendous explosion that occurred across the universe. A nearly unprecedented symphony of international observations began abruptly on March 1 when Earth-orbiting RXTE, Sun-orbiting Ulysses, and asteroid-orbiting NEAR all detected a 10-second burst of high-frequency gamma radiation.
A Panorama of Oddities in Orion A
New stars, fast jets, and shocked gas clouds all occupy Orion A, a giant molecular cloud just south of the Orion Nebula. The bright object visible below and slightly left of center of this recently released picture is the reflection nebula NGC 1999.
Supernova 1994D and the Unexpected Universe
Far away, long ago, a star exploded. Supernova 1994D, visible as the bright spot on the lower left, occurred in the outskirts of disk galaxy NGC 4526. Supernova 1994D was not of interest for how different it was, but rather for how similar it was to other supernovae. In fact, the