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Unearthing the grave of Cassiopeia A ...scientists have discovered what the star looked like in life and how it met its demise...

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Giant ring found circling monster magnetar

...a bizarre ring of material around a rare and exotic stellar corpse displays a magnetic field trillions of times more intense than the Earth’s...

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Unveiling the composition of Milky Way stars ...the most complete and detailed map yet of the chemical composition of more than 2.5 million 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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 Mission film

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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GLAST readies its gamma ray vision
BY DR EMILY BALDWIN
ASTRONOMY NOW

Posted: June 2, 2008

Excitement is mounting as the state-of-the-art Gamma ray Large Area Space Telescope (GLAST) prepares for launch later this week to explore the most extreme environments of the Universe.

The Universe is home to numerous exotic phenomena such as black holes, merging neutron stars and streams of hot plasma traveling close to the speed of light, all of which are capable of generating huge amounts of powerful gamma ray radiation. Gamma rays are the highest energy form of light in the electromagnetic spectrum, billions of times more energetic than visible light, and cannot be seen by the naked eye.

"If you're in space with gamma ray vision, there are gamma rays coming from all directions,” says GLAST Deputy Project Scientist David Thompson. “The Milky Way would be a brilliant swath of light, and you'd see a sky constantly changing with objects dimming and brightening on different time scales. If you see a blinding flash, that would be a gamma ray burst!"

GLAST will peer with unprecedented clarity into active galactic nuclei (top left), pulsars (top right), solar flares (bottom left) and supernova remnants (bottom right), helping to untangle the events that play out every day in our cosmic backyard. Images (clockwise): Sonoma State University, NASA/Chandra, NASA/Chandra and NASA/SOHO/EIT.

GLAST is a powerful space observatory that will open up this high-energy world by studying how black holes pull material in and throw out immense jets of material at phenomenal speeds, what composes the mysterious dark matter, and help crack the mysteries of the violent explosions known as gamma ray bursts. GLAST's gamma ray vision will also help to answer questions such as: How do solar flares generate high-energy particles? How do pulsars work? What is the origin of cosmic rays? and, What else is out there is shining gamma rays? Physicists will be able to study subatomic particles at energies far greater than those seen in ground-based particle accelerators and cosmologists will gain valuable information about the birth and early evolution of the Universe.

GLAST is also the first imaging gamma-ray observatory to survey the entire sky every three hours over a huge energy range. “This is important because the gamma-ray sky is constantly changing in stunning ways,” says Steve Ritz, GLAST Project Scientist. “The GLAST observatory, which also includes the GLAST Burst Monitor, spans a factor of 10 million in energy from the highest to the lowest energy gamma rays it will detect.”

The GLAST spacecraft hangs suspended, enclosed in its protective transportation canister, on launch pad 17-B at Cape Canaveral Air Force Station in Florida. Image: NASA/Kim Shiflett.

 

The GLAST spacecraft is 2.8 by 2.5 metres in diameter when stowed aboard the Delta II rocket; in space it will deploy an antenna and spread its solar arrays. The launch of NASA’s GLAST spacecraft is scheduled for Thursday June 5 from Cape Canaveral.