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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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Never before seen view of the Earth’s magnetosphere
by Jim Allen
by ASTRONOMY NOW
Posted: 19 August 2010


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A team of scientists have used NASA’s IBEX satellite to further our understanding of the solar wind's interaction with our Earth’s magnetic field and outer atmosphere.

The team, from the Southwest Research Institute (SwRI) and Lockheed Martin Space Systems Company Advanced Technology Centre (ATC), used the Interstellar Boundary Explorer (IBEX) to produce a picture of the interaction between the solar wind and the Earth’s outer atmosphere in March and April 2009.


The IBEX results demonstrating concentrations of energetic neutral atoms. The red areas show the highest concentrations towards the Sun. Image: AGU/IBEX Team.

The solar wind is a stream of sub-atomic particles produced by the Sun travelling out though the Solar System at over a million kilometres per hour. It interacts with the interstellar medium – particles of dust and gas that are distributed between the stars – to produce Energetic Neutral Atoms (ENAs). It is these ENAs that the IBEX satellite was designed and launched to study in October 2008.

Some of the protons and electrons in the solar wind are slowed by the Earth’s atmosphere 55,000 kilometres from the surface of the Earth, creating the same ENAs from particles in the outer atmosphere. Whilst IBEX is not specifically designed to study these interactions, from its position in orbit is can observe the Earth’s magnetosphere, the region where the solar wind interacts with the Earth’s magnetic field. The sensors on the satellite are perfectly designed to pick up the tiny amounts (eight atoms per cubic centimetre) of ENAs created in the magnetosphere, and it is these measurements that have created so much interest.

David McComas, the IBEX principal investigator points out “these are fantastic first images of the important region where the solar wind piles up as it deflects around the Earth’s magnetic field,” adding that “it is particularly satisfying that we were able to use a spacecraft built for a different purpose to unwrap a mystery that has long eluded us.” The IBEX measurements have been able to give a clear picture of how the concentrations of the ENAs are distributed around the Earth’s magnetosphere, with the highest number found pointing towards the Sun.

The study of these interactions is important for the preservation of the Earth’s atmosphere. “Without the Earth’s magnetosphere, which extends outward into space, the highly energetic charged particles carried by the solar wind could strip away some of Earth’s atmosphere," says Lockheed Martin’s Stephen Fuselier. "The Earth’s magnetosphere blocks the solar wind from penetrating close to the planet.”

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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