A year ago we discovered that our home galaxy is greater than we envisioned, and now comes word that its shape isn’t exactly what many have trusted it to be. Rather than being a for the most part flat spiral disk of stars and gas, new research by astronomers in China and Australia demonstrates that the Milky Way is altogether twisted at its edges.
“We usually think of spiral galaxies as being quite flat, like Andromeda, which you can easily see through a telescope,” Richard de Grijs, an astronomer at Macquarie University in Sydney, Australia, and a co-author of the paper depicting the examination, said in an announcement. The paper was distributed Feb. 5 in the journal Nature Astronomy.
We’ve all observed photographs of distant galaxies. In any case, there’s no real way to take such a photograph of the Milky Way in light of the fact that our solar system and all the space tests we’ve at any point propelled exist in it — along a finger of stars known as the Orion Spur.
Be that as it may, the astronomers could make what’s being known as the first accurate three-dimensional map of our galaxy with assistance from recently distributed information for a kind of star known as classical Cepheids. These immense, brilliant stars — up to 20 times greater and 100,000 times more brilliant than the sun — create pulsating light. They light up on occasion, diminish at others — all as per an exact and well-known schedule.
By taking a gander at the watched brightnesses and pulsation periods of 1,339 of the Cepheids, the astronomers could utilize them as a kind of cosmic yardstick to pinpoint the stars’ areas — and accordingly decide the general shape of the galaxy.
“What this paper does is to trace the warp of the stars in the disk better than has been done in the past,” Heidi Jo Newberg, an astrophysicist at Rensselaer Polytechnic Institute in Troy, New York, told NBC News MACH in an email.
The specialists presumed that the distorting is likely brought about by “torques” produced by the rotation of the vast inner disk of the Milky Way, which is a supposed barred spiral galaxy containing an expected 100 billion stars.
In any case, Newberg isn’t so certain.
“I wonder whether there might be another explanation,” she said in the email. “More recent work has shown that warps can be caused by dwarf galaxies that are orbiting, or falling into the Milky Way. Or possibly both mechanisms are at work.”