A recent study has revealed the true shape of the diffuse star cloud, known as the stellar halo, that surrounds the disk of our galaxy. Previously thought to be mostly spherical like a beach ball, a new model based on modern observations shows that the star halo elongates and curves, similar to a kicked soccer ball.

These published findings Astronomy JournalIt sheds light on a variety of astrophysical issues, including the history and evolution of our galaxy, and provides clues to the search for dark matter.

The study’s lead author, Ph.D. “The shape of the stellar halo is a very fundamental parameter that we have measured with greater precision than was possible before,” says Jiwon “Jesse” Hahn. Center for Astrophysics student at Harvard and Smithsonian University. “The fact that the halo of the star is not spherical but instead shaped like a soccer ball, a rugby ball or an airship has many important consequences – take your pick!”

“For decades, the general assumption was that the stellar halo was more or less spherical and isotropic, or the same in all directions,” adds Charlie Conroy, a co-author of the study, Khan’s advisor and professor of astronomy at Harvard University. Center for Astrophysics. “We now know that the textbook picture of our galaxy embedded in a spherical stellar volume must be discarded.”

The stellar halo of the Milky Way is the visible portion of what is more commonly referred to as the galactic halo. This galactic halo is dominated by invisible dark matter, whose existence can only be measured by the gravitational force it exerts. Each galaxy has its own dark matter halo. These halos act as a kind of scaffolding from which ordinary, visible matter hangs. In turn, this visible matter forms stars and other visible galactic structures. For better understanding how galaxies form and interact and the nature of dark matter, stellar halos are therefore valuable astrophysical targets. Source