• Email Us: [email protected]
  • Contact Us: +1 718 874 1545
  • Skip to main content
  • Skip to primary sidebar

Medical Market Report

  • Home
  • All Reports
  • About Us
  • Contact Us

Gaia Finds The Protogalaxy That Became The Milky Way’s Heart

September 22, 2022 by Deborah Bloomfield

The Milky Way is orders of magnitude larger than the other galaxies in the local group, Andromeda aside. It got that way by cannibalizing smaller galaxies. The GAIA space telescope has allowed us to identify stars of common origin, based on their movements and ages, revealing many of the conglomerations of stars that got consumed. 

There must also have been an original set of stars that have been with the Milky Way since the beginning, but identifying them is a challenge. Nevertheless, that is what Professor Hans-Walter Rix of the Max Plank Institute for Astronomy and co-authors claim to have done in a new paper still undergoing peer review.

Advertisement

One of the obstacles to finding the Milky Way’s original stars is that they must, by definition, be as old as the galaxy – around 12.5 billion years. Stars more massive than the Sun don’t last that long, so the search has to be for relatively low-mass stars. Fortunately, however, some of these stars have reached their giant stage, when stars puff up to enormous sizes, and are consequently bright enough to stand out over large distances.

Another problem is that these stars should be near the center of the galaxy – in the constellation Sagittarius from our perspective – where there is so much else going on.

“People have long speculated that such a vast population [of old stars] should exist in the center of our Milky Way,” Rix told ScienceNews. Such stars would be extremely metal-poor, composed overwhelmingly of hydrogen and helium. When the first massive stars became supernovas they produced a lot of metals and scattered them across nearby regions to be incorporated into future generations of stars. Smaller stars formed before the explosions missed out on the metals.

Advertisement

Rix and co-authors drew on GAIA’s data for 2 million stars within 30 degrees of the galactic center and found a population of 18,000 stars with less than 3 percent of the Sun’s metal concentration bunched close to the core.

As the paper explains, distinguishing between stars that were part of the original Milky Way, and those captured from smaller merged galaxies isn’t easy, since the latter can also be very metal-poor. Nevertheless, the authors believe the stars’ movements compared to the galactic center can be used to identify their origins. Extrapolating to all the stars blocked by dust or other obstacles, the authors estimate 0.2 percent of the Milky Way’s mass belongs to this original population: from little things, big things grow.

Despite all the mergers that bolstered that mass, Rix argues these fed more outlying parts of the galaxy. “We didn’t have any later mergers that deeply penetrated into the core and shook it up, because then the core would be larger now,” Rix said. 

Advertisement

The authors named their paper “The Poor Old Heart of the Milky Way,” which drew praise on Twitter as “Easily the most poetic title of a scientific paper in a long time.”

A preprint of the paper is available on ArXiv.org. 

Deborah Bloomfield
Deborah Bloomfield

Related posts:

  1. Soccer-Spurs upset Man City in controversial Women’s Super League win
  2. Shanghai suspends schools, flights as typhoon approaches China
  3. Aspire raises $158M Series B to build a full-stack “financial operating system” for Southeast Asian businesses
  4. Bank of America launches research coverage for digital assets

Source Link: Gaia Finds The Protogalaxy That Became The Milky Way’s Heart

Filed Under: News

Primary Sidebar

  • Bright Northern Lights Across America Expected This Week As 3 Coronal Mass Ejections Fly Towards Earth
  • Brain Implant Enables Paralyzed Man To Feel And Use Objects Using Someone Else’s Hands
  • “This Is A Really Big Deal”: Brain Training Significantly Improves Key Neurochemical Levels In World First
  • “Wholly Unexpected”: First-Ever Fossil Paranthropus Hand Raises Questions About Earliest Tool Makers’ Identity
  • For Centuries, Nobody Knew Why Swiss Cheese Has Holes. Then, The Mystery Was Solved.
  • Scientists Studied The Infamous “Chicago Rat Hole” And They Have Some Bad News
  • Massive 166-Million-Year-Old Sauropod Footprints Become The Longest Dinosaur Trackway In Europe
  • Do Spiders Dream? “After Watching Hundreds Of Spiders, There Is No Doubt In My Mind”
  • IFLScience Meets: ESA Astronaut Rosemary Coogan On Astronaut Training And The Future Of Space Exploration
  • What’s So Weird About The Methuselah Star, The Oldest We’ve Found In The Universe?
  • Why Does Red Wine Give Me A Headache? Many Scientists Blame It On The Grape Skins
  • Manta Rays Dive Way Deeper Than We Thought – Up To 1.2 Kilometers – To Explore The Seas
  • Prof Brian Cox Explains What He Finds “Remarkable” About Interstellar Object 3I/ATLAS Story
  • Pioneering “Pregnancy Test” Could Identify Hormones In Skeletons Over 1,000 Years Old
  • The First Neolithic Self-Portrait? Stony Human Face Emerges In 12,000-Year-Old Ruins At Karahan Tepe
  • Women Are Diagnosed With ADHD 5 Years Later Than Men, Even With Worse Symptoms
  • What Is Cryptozoology? We Explore The History And Mystery Of This Controversial Field
  • The Universe’s “Red Sky Paradox” Just Got Darker: Most Stars Might Never Host Observers
  • Uranus And Neptune May Not Be “Ice Giants” But The Solar System’s First “Rocky Giants”
  • COVID-19 Can Alter Sperm And Affect Brain Development In Offspring, Causing Anxious Behavior
  • Business
  • Health
  • News
  • Science
  • Technology
  • +1 718 874 1545
  • +91 78878 22626
  • [email protected]
Office Address
Prudour Pvt. Ltd. 420 Lexington Avenue Suite 300 New York City, NY 10170.

Powered by Prudour Network

Copyrights © 2025 · Medical Market Report. All Rights Reserved.

Go to mobile version