Astronomy Picture Of the Day (APOD)Neptune's Great Dark Spot: Gone But Not Forgotten
When NASA's Voyager 2 spacecraft flew by distant Neptune in August of 1989, astronomers were shocked. Since Neptune receives only 3 percent the sunlight Jupiter does, they expected to find a dormant, dark, frigid planet. Instead, the Voyager images revealed evidence of a dynamic and turbulent world.
Meteor Storm Sights and Sounds
This dramatic four-frame animation shows a fireball meteor and its developing persistent "smoke" train, recorded two weeks ago in skies near Salvador, Brazil. Indeed similar sights are astonishingly familiar world-wide to witnesses of this November's fireball-rich Leonid meteor storm.
The active Sun has thrown a lot our way lately, including storms of particles streaming outward in the solar wind and clouds of plasma which triggered awesome auroral displays. Still, a growing body...
Extra Solar Planetary Atmosphere Detected
By directly detecting the atmosphere of a planet outside our Solar System, humanity has taken another small step toward finding extraterrestrial life. The unexpected detection by David Charbonneau (Caltech) and associates came from Hubble Space Telescope observations of Sun-like star HD 209458.
Ancient Layered Rocks on Mars
Is this a picture of Mars or Earth? Oddly enough, it is a picture of Mars. What may appear to some as a terrestrial coastline is in fact a formation of ancient layered rocks and wind-blown sand on Mars. The above-pictured region spans about three kilometers in Schiaparelli Crater.
Leonids from the Road
Sometimes you just have to stop and watch the meteors. In the early morning hours of November 18, a band of eleven people searched for a flat and cloudless site to see the 2001 Leonids Meteor Shower.
M16: Stars from Eagle's EGGs
Newborn stars are forming in the Eagle Nebula. This image, taken with the Hubble Space Telescope in 1995, shows evaporating gaseous globules (EGGs) emerging from pillars of molecular hydrogen gas and dust. The giant pillars are light years in length and are so dense that interior gas contracts gravitationally to form stars.
Mariner s Mercury
Mercury, the closest planet to the Sun, remains the most mysterious of the Solar System's inner planets. Hiding in the Sun's glare it is a difficult target for Earth bound observers.
Counting Falling Stardust
In the clear, dark and moonless predawn hours of November 18, Greenbelt, Maryland's local baseball field was packed. The crowd stared skyward and occasionally conversed in hushed and reverent tones. "How many did you count?" a man asked.
Fireball, Smoke Trail, Meteor Storm
Returning from orbit, space shuttles enter the atmosphere at about 8 kilometers per second as friction heats their protective ceramic tiles to over 1,400 degrees Celsius. By contrast, the bits of comet dust...