In findings that help astrophysicists understand our corner of the galaxy, an international research team has shown that the soft X-ray glow blanketing the sky comes from both inside and outside the solar system.
The source of this “diffuse X-ray background” has been debated for the past 50 years. Does it originate from the solar wind colliding with interplanetary gases within our solar system? Or is it born further away, in the “local hot bubble” of gas that a supernova is believed to have left in our galactic neighborhood about ten million years ago?
The scientists found evidence that both mechanisms contribute, but the bulk of the X-rays come from the bubble. The solar wind, a stream of charged particles continuously emitted by the Sun, appears to be responsible for at most 40 percent of the radiation, according to new findings published in the journal Nature.
“The overarching science goal of our work is to try to answer questions like: What does the local astrophysical environment look like? And what is the environment in which the Sun was born?” said Susan Lepri, an associate professor of atmospheric, oceanic and space sciences in the University of Michigan College of Engineering.
“It’s part of trying to understand our place in the universe.” Read More …