Our Milky Way galaxy is surrounded by a hot halo, scientists say
Our galaxies is surrounded by a halo that is much hotter than scientists previously thought, according to new research.
What's more, other galaxies could be wrapped in the same hot ring.
Scientists had already found that the halo, which is made up of dust, gas and dark matter that is wrapped around our galaxy, was at least 10 times hotter than had known before. But there was nothing to suggest that one measurement was not simply just an especially warm part of the halo, rather than an indication of conditions elsewhere.
Now new research suggests those extreme temperatures might actually be found right across the entire halo, and could be found in similar places around other galaxies.
"We can't say for sure that it is everywhere, because we have not analyzed the entire halo," said Smita Mathur, professor of astronomy at Ohio State. "But we know now that the temperatures we saw in the first study definitely are not unique, and that is very exciting."
The new findings could help researchers understand the halos, as well as how they and the galaxies they surround are formed. The halo marks the threshold between our Milky Way and the wider universe, and so could help offer clues about how galaxies grow and change.
"We are trying to learn about the elements that form these halos, and about the temperatures there," she said. "Knowing those things can help us understand more about how galaxies connect with the rest of the universe, and how they formed and where elements might have come from."
