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Landscaping the cosmos

...The Hubble Heritage Project celebrates its 10th anniversary this month with a beautiful landscape image of the ‘hills’ and ‘valleys’ of gas and dust in the giant gaseous cavity of star-forming region NGC 3324...

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COROT discovery stirs exoplanet classification rethink

...COROT scientists have discovered the most massive planet-sized object closely orbiting its parent star yet, but is it really a planet or is it a failed star?...

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Cloudy weather on failed star twins

...A team of astronomers using one of the Keck telescopes on Mauna Kea has found evidence for cloudy weather on two failed stars...

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STS-120 day 2 highlights

Flight Day 2 of Discovery's mission focused on heat shield inspections. This movie shows the day's highlights.

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STS-120 day 1 highlights

The highlights from shuttle Discovery's launch day are packaged into this movie.

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STS-118: Highlights

The STS-118 crew, including Barbara Morgan, narrates its mission highlights film and answers questions in this post-flight presentation.

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STS-120: Rollout to pad

Space shuttle Discovery rolls out of the Vehicle Assembly Building and travels to launch pad 39A for its STS-120 mission.

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Dawn leaves Earth

NASA's Dawn space probe launches aboard a Delta 2-Heavy rocket from Cape Canaveral to explore two worlds in the asteroid belt.

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Dawn: Launch preview

These briefings preview the launch and science objectives of NASA's Dawn asteroid orbiter.

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Small asteroid burns up in Earth’s atmosphere
BY DR EMILY BALDWIN
ASTRONOMY NOW

Posted: October 07, 2008

According to predictions, three metre wide asteroid 2008TC3 exploded in the Earth’s atmosphere at 0246 UT above northern Sudan this morning.

Asteroid 2008TC3 was discovered on 6 October at around 0630 UT. The asteroid was at 19th magnitude and moving at a rate of 2.5 degrees per day. Image: R. Kowalski, E. Beshore, Catalina Sky Survey.

The asteroid was found on Monday morning by the Catalina Sky Survey’s observatory in Arizona and calculations by the Minor Planet Center suggested that the object would enter the Earth’s atmosphere less than a day later, creating a bright fireball. This fireball effect is created as the meteoroid (that is, a small asteroid) compresses the air in front of it, heating it up and causing it to glow, fragment and vapourise.

The burning meteroid was predicted to travel west to east across northern Sudan in Africa at around 12.8 kilometres per second, plunging through the atmosphere at an angle of 19 degrees from the horizontal. It is not thought that any fragments would survive the fury transit through the atmosphere.

"We estimate objects this size enter Earth's atmosphere once every few months," says Don Yeomans of the Near-Earth Object Office at NASA's Jet Propulsion Laboratory in Pasadena. "The unique aspect of this event is that it is the first time we have observed an impacting object during its final approach."

The orbit of Asteroid 2008 TC3 was predicted to collide with that of the Earth at 0246 UT this morning. Image: Near Earth Object Program.

According to a report posted on spaceweather.com, KLM airliner crew flying in the area observed a short flash just before the predicted impact time.

The discovery of such an impactor so close to home is also a solemn reminder of how an asteroid impact could take the Earth by surprise without any considerable warning.