Astronomy Picture Of the Day (APOD)Dark Sand Cascades on Mars
They might look like trees on Mars, but they're not. Groups of dark brown streaks have been photographed by the Mars Reconnaissance Orbiter on melting pinkish sand dunes covered with light frost. The above image was taken in 2008 April near the North Pole of Mars.
Eclipse over the Temple of Poseidon
What's happened to the Sun? The Moon moved to partly block the Sun for a few minutes last week as a partial solar eclipse became momentarily visible across part of planet Earth.
Atlantis to Orbit
Birds don't fly this high. Airplanes don't go this fast. The Statue of Liberty weighs less. No species other than human can even comprehend what is going on, nor could any human just a millennium ago. The launch of a rocket bound for space is an event that inspires awe and challenges description.
New Year Sun Grazer
Intense and overwhelming, the direct glare of the Sun is blocked by the smooth occulting disk in this image from the sun-staring SOHO spacecraft. Taken on January 3rd, an extreme ultraviolet image of the Sun to scale, is superimposed at the center of the disk.
Scenes from Two Hemispheres
The stars of a summer night on the left and the winter night sky on the right are the same stars. In fact, both pictures were taken in late December and have similar fields of view.
M94: A New Perspective
Beautiful island universe M94 lies a mere 15 million light-years distant in the northern constellation of the hunting dogs, Canes Venatici. A popular target for astronomers the brighter inner part of the face-on spiral galaxy is about 30,000 light-years across.
The Spider and the Fly
Bright clusters and nebulae abound in the ancient northern constellation of Auriga. The region includes the open star cluster M38, emission nebula IC 410 with Tadpoles, Auriga's own Flaming Star Nebula IC 405, and this interesting pair IC 417 (lower left) and NGC 1931.
The Flame Nebula in Infrared
What lights up the Flame Nebula? Fifteen hundred light years away towards the constellation of Orion lies a nebula which, from its glow and dark dust lanes, appears, on the left, like a billowing fire. But fire, the rapid acquisition of oxygen, is not what makes this Flame glow.
The Astronaut Who Captured a Satellite
In 1984, high above the Earth's surface, an astronaut captured a satellite. It was the second satellite captured that mission. Pictured above, astronaut Dale A. Gardner flies free using the Manned Maneuvering Unit and begins to attach a control device dubbed the Stinger to the rotating Westar 6 satellite.
A Spherule from the Earths Moon
How did this spherule come to be on the Moon? When a meteorite strikes the Moon, the energy of the impact melts some of the splattering rock, a fraction of which might cool into tiny glass beads. Many of these glass beads were present in lunar soil samples returned to Earth by the Apollo missions.