Astronomy Picture Of the Day (APOD)A Lenticular Cloud Over Hawaii
Can a cloud do that? Actually, pictured above are several clouds all stacked up into one striking lenticular cloud. Normally, air moves much more horizontally than it does vertically. Sometimes, however, such as when wind comes off of a mountain or a hill, relatively strong vertical oscillations take place as the air stabilizes.
The Stars of NGC 300
Like grains of sand on a cosmic beach, individual stars of large spiral galaxy NGC 300 are resolved in this sharp image from the Hubble Space Telescope's Advanced Camera for Surveys (ACS). The inner region of the galaxy is pictured, spanning about 7,500 light-years.
NGC 1 and NGC 2
Beautiful nebulae, clusters, and galaxies that grace planet Earth's night sky are often known by their New General Catalog designation or NGC number. That classic listing was compiled by John Louis Emil Dreyer, remarkable director of the Armagh Observatory from 1882 to 1916.
Sylvia, Romulus and Remus
Discovered in 1866, main belt asteroid 87 Sylvia lies 3.5 AU from the Sun, between the orbits of Mars and Jupiter. Also shown in recent years to be one in a growing list...
Planets over Paranal
Very bright planets and very large telescopes are part of this sunset view of Paranal Observatory. The observatory's four, massive 8.2 meter telescope units are situated on top of the 2,600 meter high mountain, Cerro Paranal, in the dry Atacama Desert in northern Chile.
The International Space Station from Orbit
The International Space Station (ISS) is the largest human-made object ever to orbit the Earth. Late last month and earlier this month, the station was visited and resupplied by space shuttle Discovery. The ISS is currently operated by the Expedition 11 crew, consisting a Russian and an American astronaut.
Perseid Meteors and the Milky Way
Where will the next Perseid meteor appear? Sky enthusiasts who trekked outside for the Perseid meteor shower that peaked over the past few days typically had this question on their mind. The above movie, where the time-line has been digitally altered, captures part of that very mystery.
Heating Coronal Loops
Why is the corona of the Sun so hot? Extending above the photosphere or visible surface of the Sun, the faint, tenuous solar corona can't be easily seen from Earth, but it is measured to be hundreds of times hotter than the photosphere itself.
SNR 0103 72.6: Oxygen Supply
A supernova explosion, a massive star's inevitable and spectacular demise, blasts back into space debris enriched in the heavy elements forged in its stellar core. Incorporated into future stars and planets, these are the elements ultimately necessary for life. Seen here in a false-color x-ray image, supernova remnant SNR 0103-72
A Meteor Shower Fireball Movie
Go outside tonight and see a celestial light show -- the later the better. Tonight is the peak of the month-long Perseid Meteor Shower. Although visible every year at this time, the Perseids are expected to appear particularly active this year due to the relative absence of glare from the Moon during the peak.