Astronomy Picture Of the Day (APOD)ERAST Pathfinder Plus: Daedalus Defied
Daedalus warned Icarus that if he flew too high, the Sun would melt his wings. Apparently, nobody gave the ERAST Pathfinder-Plus aircraft a similar warning. Earlier this month, not only did Pathfinder-Plus fly higher than any previous propeller-driven aircraft - its wings converted sunlight into power.
Hot gas dances across the surface of the Sun in this picture from the orbiting TRACE satellite. The temperature of the gas is color coded so that blue represents hundreds of thousands of Kelvin, while red represents extreme temperatures in the millions of Kelvin.
Meteors Now and Again
The Perseid Meteor Shower, usually the best meteor shower of the year, will peak over the next two nights. Over the course of an hour, a person watching a clear sky from a dark location might see as many as 100 meteors.
Shapley 1: An Annular Planetary Nebula
What happens when a star runs out of nuclear fuel? The center condenses into a white dwarf while the outer atmospheric layers are expelled into space and appear as a planetary nebula. This particular planetary nebula, designated Shapley 1 after the famous astronomer Harlow Shapley, has a very apparent annular ring like structure.
The Cygnus Loop
15,000 years ago a star in the constellation of Cygnus exploded -- the shockwave from this supernova explosion is still expanding into interstellar space! The collision of this fast moving wall of gas with...
M65 Without Moth
Messier 65 (M65) is a bright spiral galaxy of stars only 35 million light-years away in the constellation Leo. With very tightly wound spiral arms, a large central bulge, and well defined dust lanes, this galaxy is a member of a group of galaxies known as the Leo triplet.
This famous cosmic dust cloud was imaged in infrared light by the European Space Agency's Infrared Space Observatory (ISO) satellite. The false-color picture shows the bright infrared emission from dust and molecular gas in part of the Orion star forming region surrounding the Horsehead Nebula.
Ganymede: Torn Comet Crater Chain
This remarkable line of 13 closely spaced craters on Jupiter's moon Ganymede was photographed by the Galileo spacecraft in 1997. The picture covers an area about 120 miles wide and the chain of craters cuts across a sharp boundary between dark and light terrain. What caused this crater chain?
Jupiter Swallows Comet Shoemaker Levy 9
What happens when a comet encounters a planet? If the planet has a rocky surface, a huge impact feature will form. A giant planet like Jupiter, however, is mostly gas. When Comet Shoemaker-Levy 9 struck Jupiter in 1994, each piece was swallowed into the vast Jovian atmosphere.
M44: A Beehive of Stars
M44 is a prominent open cluster of stars. Nicknamed Praesepe and "The Beehive", it is one of the few open clusters visible to the unaided eye. M44 was thought to be a nebula until Galileo used an early telescope to resolve the cluster's bright blue stars. These stars are visible in the above image.