For many years, astronomers had been trying to understand what’s causing the Milky Way’s shape. As we know that the supermassive black hole from the center plays a crucial role for that matter, scientists were also curious to find out why a stream of gas is surrounding our galaxy.
More precisely, the stream in question is known as the Magellanic Stream, and it was a mystery for why it’s over a billion times the mass of the sun. Furthermore, astronomers from the University of Wisconsin-Madison have discovered that a halo of warm gas surrounds the Magellanic Clouds and it shields the dwarf galaxies from the Milky Way’s halo.
The halo is stretched and dispersed to form the Magellanic Stream
Scott Lucchini, first author of the paper and a graduate student in the UW-Madison physics department, declared:
The existing models of the formation of the Magellanic Stream are outdated because they can’t account for its mass,
Elena D’Onghia, supervisor of the research and a professor of astronomy at UW-Madison, declared:
That’s why we came out with a new solution that is excellent at explaining the mass of the stream, which is the most urgent question to solve,
The creation process of the Magellanic Stream is divided in two periods. The Large Magellanic Cloud stripped gas away from its smaller partner. This stolen gas contributed 10 to 20 percent of the final mass of the stream. And when the clouds fell into the Milky Way’s orbit, the corona gave up a fifth of its mass to form the Magellanic Stream. The latter stream was stretched across an enormous arc of the sky by interacting with the Milky Way’s gravity and its corona.
Joss Bland-Hawthorn, a co-author of the study paper and director of the Sydney Institute for Astronomy in Australia, said:
This work redefines our understanding of how gas accretes onto the Milky Way and forms the reservoir for future star formation
The findings were published in the journal Nature.