by Nancy Atkinson on January 25, 2013

Thor’s Helmet Nebula (NGC 2359) in the constellation  of Canis Major. Credit and copyright: Rolf Wahl Olsen.

At first glance, you might expect this beautiful image to be from a big  ground-based observatory or even one of the space telescopes. But this image was  taken by “amateur” astronomer Rolf Wahl Olsen.  We’ve featured his work before, and he’s  done amazing stuff – such as the first amateur image of another solar system — but even  he says this latest image of an emission nebula might be his best image to date.

It’s a stunning look at what is known as Thor’s Helmet.  This helmet-shaped  feature (complete with wings!) is an emission nebula is located in the  constellation of Canis Major, about 15,000 light years from Earth. The nebula is  a large expanding bubble illuminated by a central star in its last stage of life — a massive Wolf-Rayet star which is shedding its outer layers of gas at an  extremely high rate due to intense radiation pressure. Wolf-Rayet stars are  thought to represent a brief stage of evolution near the end of life for giant  super massive stars; the last unstable phase before the star explodes as a  brilliant supernova. [click  to continue…]

 

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by Leonard  David, SPACE.com’s Space Insider Columnist

The saga of what steps that must be taken to deal with the evolving threat of Earth-circling orbital debris is a work in progress.  This menacing problem — and the possible cleanup solutions — is international in scope.

Space junk is an assortment of objects in Earth orbit that is a mix of everything from spent rocket stages, derelict satellites, chunks of busted up spacecraft to paint chips, springs and bolts. A satellite crash in February 2009, for example, marked the first accidental hypervelocity crash between two intact artificial satellites in Earth orbit. That cosmic crash created significant debris — a worrisome amount of leftover bits and pieces.

Against this backdrop of untidiness in space and the global worry among spacefaring countries it causes, experts continue to tackle the issue of exactly what to do about orbital debris. A number of rules have been pondered to address the space debris problem, from regulations that attempt to cut down on the shedding of new debris to better tracking of the human-made refuge, as well as scavenging concepts including fishing nets, lasers and garbage scows.

But how to best characterize the orbital debris dilemma, and its future, also stirs up debate and heated dialogue.

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