November 22, 2024

Galactic Surprise: Milky Way’s Slower Outer Stars Suggest Dark Matter Overestimated

Credit: SciTechDaily.comMITs study shows outer Milky Way stars rotate slower, indicating a lighter core with less dark matter, contradicting previous assumptions.By clocking the speed of stars throughout the Milky Way galaxy, MIT physicists have discovered that stars further out in the galactic disk are taking a trip more gradually than expected compared to stars that are better to the galaxys. The physicists evaluated Gaias measurements of more than 33,000 stars, including some of the farthest stars in the galaxy, and determined each stars “circular velocity,” or how fast a star is circling in the galactic disk, offered the stars range from the galaxys center.Understanding Galactic RotationThe researchers outlined each stars velocity against its range to produce a rotation curve– a basic chart in astronomy that represents how quick matter rotates at a provided range from the center of a galaxy. They concluded that some other type of invisible matter must be acting on distant stars to give them an included push.Rubins work in rotation curves was one of the first strong pieces of proof for the existence of dark matter– an undetectable, unidentified entity that is estimated to outweigh all the stars and other noticeable matter in the universe.Since then, astronomers have actually observed comparable flat curves in far-off galaxies, even more supporting dark matters existence.”The team developed the accurate distances for more than 33,000 stars and used these measurements to produce a three-dimensional map of the stars spread throughout the Milky Way out to about 30 kiloparsecs. They then integrated this map into a model of circular velocity, to imitate how quick any one star must be taking a trip, offered the circulation of all the other stars in the galaxy.

Credit: SciTechDaily.comMITs study reveals external Milky Way stars rotate slower, showing a lighter core with less dark matter, contradicting previous assumptions.By clocking the speed of stars throughout the Milky Way galaxy, MIT physicists have found that stars even more out in the galactic disk are traveling more gradually than expected compared to stars that are closer to the galaxys. The physicists examined Gaias measurements of more than 33,000 stars, consisting of some of the farthest stars in the galaxy, and figured out each stars “circular velocity,” or how fast a star is circling around in the stellar disk, offered the stars distance from the galaxys center.Understanding Galactic RotationThe researchers outlined each stars speed against its distance to produce a rotation curve– a standard chart in astronomy that represents how quick matter turns at a given range from the center of a galaxy. They concluded that some other type of unnoticeable matter must be acting on distant stars to give them an added push.Rubins work in rotation curves was one of the first strong pieces of proof for the existence of dark matter– an invisible, unknown entity that is estimated to exceed all the stars and other noticeable matter in the universe.Since then, astronomers have observed comparable flat curves in far-off galaxies, further supporting dark matters presence.