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Lunar tandem successfully enters orbit around the Moon
...Ringing in the new year with back-to-back successes, a second NASA science satellite slipped into orbit around the moon Sunday, one day after an identical spacecraft braked into the same polar orbit for a $496 million mission to map the moon's interior by precisely measuring how its gravity affects the trajectories of the twin spacecraft...
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Astronomy Now's year in space
...Pluto’s new moon, salty water on Mars, interstellar travel and black trees on a world with two suns; look back over the year as we count down the most read news stories of 2011...
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First “mini-Earth” discovered around Sun-like star
...A rocky exoplanet smaller than Earth, and its neighbouring Earth-sized world with a thick water-vapour atmosphere, have been detected around a Sun-like star already known to host three larger planets....
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Distant GRB blueprint of early Universe
DR EMILY BALDWIN
ASTRONOMY NOW
Posted: October 29, 2009


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A powerful gamma-ray burst (GRB) detected by NASA's Swift satellite in April – the most distant object ever discovered – continues to provide tantalizing insight into the nature of objects born in the early Universe.

“This observation allows us to begin exploring the last blank space on our map of the Universe,” says Professor Nial Tanvir of the University of Leicester.

GRB 090423 is located at a spectacularly distant 13 billion light years, emanating from a star that exploded when the Universe was just 630 million years old. Most GRBs occur as their progenitor stars run out of fuel and collapse into a black hole or neutron star, shooting out jets of radiation through previously expelled layers of gas, which interact to generate short-lived afterglows in other wavelengths.

Data from Swift's Ultraviolet/Optical (blue, green) and X-Ray (orange and red) telescopes are merged in this image. No visible light accompanied the burst, which alone suggests great distance. The image is 6.3 arcminutes across. Image: NASA/Swift/Stefan Immler.

“This explosion provides an unprecedented look at an era when the Universe was very young and also was undergoing drastic changes,” says Dale Frail of the National Radio Astronomy Observatory. “The primal cosmic darkness was being pierced by the light of the first stars and the first galaxies were beginning to form. The star that exploded in this event was a member of one of these earliest generations of stars.”

Astronomers using the Very Large Array (VLA) detected the first radio waves a week following the Swift detection, and recorded changes in the object until it faded from view more than two months later. Much of the light was in the form of very high energy gamma rays, fading into infrared wavelengths.

“It’s important to study these explosions with many kinds of telescopes,” says Derek Fox of Pennsylvania State University. “Our research team combined data from the VLA with data from X-ray and infrared telescopes to piece together some of the physical conditions of the blast. The result is a unique look into the very early Universe that we couldn’t have gotten any other way.”

The combined data collection efforts reveal that the explosion of the progenitor star was more energetic than other known GRBs, a near-spherical blast that expanded into a tenuous and relatively uniform gaseous medium surrounding the star. Astronomers suspect that the Universe's first inhabitants were brighter, hotter and more massive than those that formed later, and hope to build evidence for this theory in the shape of even more distant GRBs. While the data on GRB 090423 don’t indicate that it resulted from the death of such a monster star, new astronomical tools are coming that may reveal them.

“The Atacama Large Millimeter/submillimeter Array (ALMA), will allow us to pick out these very-distant GRBs more easily so we can target them for intense follow-up observations,” says Frail. “The Expanded Very Large Array, with much greater sensitivity than the current VLA, will let us follow these blasts much longer and learn much more about their energies and environments. We’ll be able to look back even further in time.”

Both ALMA and the EVLA are scheduled for completion in 2012.

The Planets
From tiny Mercury to distant Neptune and Pluto, The Planets profiles each of the Solar System's members in depth, featuring the latest imagery from space missions. The tallest mountains, the deepest canyons, the strongest winds, raging atmospheric storms, terrain studded with craters and vast worlds of ice are just some of the sights you'll see on this 100-page tour of the planets.
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Hubble Reborn
Hubble Reborn takes the reader on a journey through the Universe with spectacular full-colour pictures of galaxies, nebulae, planets and stars as seen through Hubble's eyes, along the way telling the dramatic story of the space telescope, including interviews with key scientists and astronauts.
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3D Universe
Witness the most awesome sights of the Universe as they were meant to be seen in this 100-page extravaganza of planets, galaxies and star-scapes, all in 3D!
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Infinity Rising
This special publication features the photography of British astro-imager Nik Szymanek and covers a range of photographic methods from basic to advanced. Beautiful pictures of the night sky can be obtained with a simple camera and tripod before tackling more difficult projects, such as guided astrophotography through the telescope and CCD imaging.
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Starry Night
Explore the Universe with these new versions of the award-winning Starry Night Software. Available now from the Astronomy Now Store.
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Exploring Mars
Astronomy Now is pleased to announce the publication of Exploring Mars. The very best images of Mars taken by orbiting spacecraft and NASA's Spirit and Opportunity rovers fill up the 98 glossy pages of this special edition!
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Mars rover poster
This new poster features some of the best pictures from NASA's amazing Mars Exploration Rovers Spirit and Opportunity.
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