Please Register or Log in to view the hidden image! X-Ray Mystery in RCW 38 Credit: S. Wolk (CfA), et al., CXC, NASA A mere 6,000 light-years distant and sailing through the constellation Vela, star cluster RCW 38 is full of powerful stars. It's no surprise that these stars, only a million years young with hot outer atmospheres, appear as point-like x-ray sources dotting this x-ray image from the orbiting Chandra Observatory. But the diffuse cloud of x-rays surrounding them is a bit mysterious. The image is color coded by x-ray energy, with high energies in blue, medium in green, and low energy x-rays in red. Just a few light-years across, the cloud which pervades the cluster has colors suggesting the x-rays are produced by high energy electrons moving through magnetic fields. Yet a source of energetic electrons, such as shockwaves from exploding stars (supernova remnants), or rotating neutron stars (pulsars), is not apparent in the Chandra data. Whatever their origins, the energetic particles could leave an imprint on planetary systems forming in young star cluster RCW 38, just as nearby energetic events seem to have affected the chemistry and isotopes found in our own solar system.
possible explanations The electrons might have been produced by an exploding star, called a supernova, that faded away thousands of years ago. In such an event, a shock wave or a rapidly rotating and very dense neutron star, produced by the catastrophe, could be acting in concert with other energized stellar winds to produce the high-energy electrons. "Regardless of the origin of the energetic electrons," said Wolk, "their presence would change the chemistry of protostellar disks in ways that could still be manifest billions of years later." An example might be found in our own solar system, which is about 4.6 billion years old. There is evidence here for certain short-lived radioactive nuclides that imply the existence of a high-energy process. If our solar system was immersed for a time in a sea of energetic particles, this could explain the rare nuclides present in meteorites found on the Earth today. http://www.space.com/scienceastronomy/xray_supernova_021219.html