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"I want to know why the universe exist, why there is something greater than nothing."

Steven Hawking

Scientist, Space Lover

A Proton Arc Over Lake Superior

The setting had been picked out -- all that was needed was an aurora. And late last August, forecasts predicted that an otherwise beautiful night sky would be lit up with auroral green. Jumping into his truck, the astrophotographer approached his secret site -- but only after a five hour drive across the rural Upper Peninsula of Michigan. What he didn't know was that his luck was just beginning. While setting up for the image, a proton arc -- a rare type of aurora -- appeared. The red arc lasted only about 15 minutes, but that was long enough to capture in a 30-second exposure. As the name indicates, proton arcs are caused not by electrons but by more massive protons that bombard the Earth's atmosphere following an energetic event on the Sun. In the featured image, the yellow lights on the horizon are the city lights of Marquette, Michigan, USA. The blue and yellow rocks in the Lake Superior foreground are lit by a LED flashlight. Also captured, to the left of the red proton arc, was the band of our Milky Way Galaxy. APOD Editor to Speak: Saturday, August 8 at Keweenaw Science & Engineering Festival

Stereo Saturn

Get out your red/blue glasses and launch yourself into this stereo picture of Saturn! The picture is actually composed from two images recorded weeks apart by the Voyager 2 spacecraft during its visit to the Saturnian System in August of 1981. Traveling at about 35,000 miles per hour, the spacecraft's changing viewpoint from one image to the next produced this exaggerated but pleasing stereo effect. Saturn is the second largest planet in the Solar System, after Jupiter. Its spectacular ring system is so wide that it would span the space between the Earth and Moon. Although they look solid here, Saturn's rings consist of individually orbiting bits of ice and rock ranging in size from grains of sand to barn-sized boulders.

Introducing Nova Velorum 1999

A bright nova was discovered Saturday that is currently visible to the unaided eye in southern skies. Nova Velorum 1999 was recorded near visual magnitude 3 independently by discoverers Peter Williams and Alan C. Gilmore (Mt. John U. Obs.), making it more luminous than many famous bright stars. The last nova this bright was Nova Cygni 1975, which peaked just brighter than magnitude 2. Nova Velorum 1999 is brighter now than the well-studied Nova Cygni 1992 ever appeared. A nova occurs when the surface of a white dwarf star undergoes a tremendous thermonuclear explosion, throwing off its outer layers. How the nova will appear over the next few weeks is uncertain, but the exploding debris will likely fade beyond detectability over the next few years. The above photograph of Nova Velorum 1999 was taken yesterday from Australia. The cross-hair like spikes that appear around it were caused by the photographing telescope and camera.



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