"Caruso"
2017-12-28
2017-12-27
Astronomy picture of the day - 2017 December 26 - Grand Spiral Galaxy NGC 1232
Image Credit: FORS, 8.2-meter VLT Antu, ESO
Explanation: Galaxies are fascinating not only for what is visible, but for what is invisible. Grand spiral galaxy NGC 1232, captured in detail by one of the Very Large Telescopes, is a good example. The visible is dominated by millions of bright stars and dark dust, caught up in a gravitational swirl of spiral arms revolving about the center. Open clusters containing bright blue stars can be seen sprinkled along these spiral arms, while dark lanes of dense interstellar dustcan be seen sprinkled between them. Less visible, but detectable, are billions of dim normal stars and vast tracts of interstellar gas, together wielding such high mass that they dominate the dynamics of the inner galaxy. Leading theories indicate that even greater amounts of matter are invisible, in a form we don't yet know. This pervasive dark matter is postulated, in part, to explain the motions of the visible matter in the outer regions of galaxies.
2017-12-26
Astronomy picture of the day - 2017 December 25 - Fireball in the Arctic
Image Credit & Copyright: Yang Sutie
Explanation: Something very bright suddenly lit up the arctic -- what was it? The original idea was to take a series of aurora images that could be made into a time-lapse video. But when night suddenly turned into day, the astrophotographer quickly realized that he was seeing something even more spectacular. Moving through the sky -- in front of the Big Dipper no less -- was a Geminid meteor so bright it could be called a fireball. The meteor brightened and flashed for several seconds as it went. By a stroke of good fortune, the aurora camera was able to capture the whole track. Taken the night after the Geminids Meteor Shower peaked, the astrophotographer's location was nearLovozero Lake in Murmansk, Russia, just north of the Arctic Circle.
2017-12-24
Astronomy picture of the day - 2017 December 24 - SpaceX Rocket Launch Plume over California
Image Credit & Copyright: Craig Bobchin
Explanation: What's happened to the sky? On Friday, the photogenic launch plume from a SpaceX rocket launch created quite a spectacle over parts of southern California and Arizona. Looking at times like a giant space fish, the impressive rocket launch from Vandenberg Air Force Base near Lompoc, California, was so bright because it was backlit by the setting Sun. Lifting off during a minuscule one-second launch window, the Falcon 9 Heavy rocket successfully delivered to low Earth orbit ten Iridium NEXT satellites that are part of a developing global communications network. The plume from the first stage is seen on the right, while the soaring upper stage rocket is seen at the apex of the plume toward the left. Several good videos of the launch were taken. The featured image was captured from Orange County, California, in a 2.5 second duration exposure.
2017-12-23
Astronomy picture of the day - 2017 December 23 - Phaethon's Brood
Image Credit & Copyright: Mikiya Sato (Nippon Meteor Society)
Explanation: Based on its well-measured orbit, 3200 Phaethon (sounds like FAY-eh-thon) is recognized as the source of the meteroid stream responsible for the annual Geminid meteor shower. Even though most meteor showers' parents are comets, 3200 Phaethon is a known and closely tracked near-Earth asteroid with a 1.4 year orbital period. Rocky and sun-baked, its perihelion or closest approach to the Sun is well within the orbit of innermost planet Mercury. In this telescopic field of view, the asteroid's rapid motion against faint background stars of the heroic constellation Perseus left a short trail during the two minute total exposure time. The parallel streaks of its meteoric children flashed much more quickly across the scene. The family portrait was recorded near the Geminid meteor shower's very active peak on December 13. That was just before 3200 Phaethon's historic December 16 closest approach to planet Earth.
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