The “fossil” of the first generation galaxy?A new very dark dwarf galaxy found | sorae Portal site to space

Facebook
Twitter
LinkedIn
Pinterest
Pocket
WhatsApp

[▲Ultra-lowlightdwarfgalaxy”PegasusV”anditssurroundings(Credit:InternationalGeminiObservatory/NOIRLab/NSF/AURA;Imageprocessing:TARector(UniversityofAlaskaAnchorage/NSF’sNOIRLab)MZamani(NSF’sNOIRLab)&DdeMartin(NSF’sNOIRLab))】

Astronomer at Sally UniversityMichelle CollinsThe research team led by is about 2.5 million light-years away from the earth.A new type of galaxy called “Ultra-Faint Dwarf Galaxy” has been found around the “Andromeda Galaxy (M31)”.We announced the research results.

Because this galaxy is the fifth dwarf galaxy found in Pegasus“Pegasus V”It was named. According to the research team, the distance from Earth to Pegasus V is about 2.25 million light-years, and about 800,000 light-years from the Andromeda Galaxy. You can see Pegasus V in the image at the beginning. Could you find out where it is in the image? (Annotated image showing location is posted later in the article)

■ Pegasus V may be a “fossil” -like object of the first galaxy

The dwarf galaxyThe number of stars is billions or lessIt is a general term for small galaxies. The dwarf galaxy is a galaxy with a low surface brightness (dark), but as the name implies, the ultra-low brightness dwarf galaxy is a particularly dark type of galaxy. The dark dwarf galaxy is thought to be a galaxy that has survived since ancient times and is expected to contain clues about the earliest formed stars.

In recent years, in the local galaxies to which the Milky Way and Andromeda galaxies belong, a number of dark dwarf galaxies that could not be observed before have been found. However, according to the National Institute of Optical and Infrared Astronomy (NOIRLab) of the American Science Foundation (NSF), which released the image,The number of dark dwarf galaxies found so far is less than theoretically predictedIt seems that.

If the number of dark dwarf galaxies is really smaller than theoretically predicted, it means that there is a serious problem in cosmology and understanding of dark matter. Dwarf galaxies are also important to researchers, although they look quite different from the magnificent spiral galaxies with their spiral arms spread out and the active elliptical galaxies that spew jets.

[▲Ultra-low-intensitydwarfgalaxy”PegasusV”anditssurroundingsPegasusVisatthelocationindicatedbythecircle(Credit:InternationalGeminiObservatory/NOIRLab/NSF/AURA;Imageprocessing:TARector(UniversityofAlaskaAnchorage/NSF’sNOIRLab)MZamani(NSF’sNOIRLab)&DdeMartin(NSF’sNOIRLab))】

Pegasus V is an observation device for the Blanco 4m telescope at the Astronomical Observatory of Cyril and Trolo in Chile.“Dark Energy Camera (DECam)”An amateur astronomy person who was checking images taken withGiuseppe DonatielloWas discovered by.

The research team at the Gemini Observatory on Mauna Kea, Hawaii“Gemini North Telescope”When we made another observation using, in addition to clarifying the distance to Pegasus V,Very scarce of metals (here, elements heavier than hydrogen and helium)It is said that he also understood that.

Metal is produced by the fusion reaction inside the star, and after being released to the surroundings by the stellar wind or supernova explosion, it becomes the material of a new star. for that reason,As the generations of stars change, the amount of metal in the galaxy gradually increases.It will be. Low metal means that star-forming activity in the galaxy stopped early.

According to the research team, Pegasus V is one of the darkest dwarf galaxies found around the Andromeda Galaxy, which is particularly poor in metal and is a collection of very old stars in this universe.Possibility of being a “fossil” -like object of the first generation galaxyIt is said that there is.

Collins through a study of the chemistry of Pegasus VClue about star formation in the earliest universeWith the expectation that Pegasus V will be obtainedMay be useful in understanding galaxy formation and dark matterI am saying.Early galaxies“James Webb”Although it is one of the observation targets of the Space Telescope, “fossil fossils of early galaxies” may be found in unexpectedly close places in the future.

Related: New images of four “neighborhood” galaxies released

Source

  • Image Credit: International Gemini Observatory/NOIRLab/NSF/AURA; Image processing: T.A. Rector (University of Alaska Anchorage/NSF’s NOIRLab), M. Zamani (NSF’s NOIRLab) & D. de Martin (NSF’s NOIRLab)
  • NOIRLab – Gemini North Spies Ultra-Faint Fossil Galaxy Discovered on Outskirts of Andromeda

Text/Matsumura Takehiro

Facebook
Twitter
LinkedIn
Pinterest
Pocket
WhatsApp

Leave a Reply

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Recent News

Editor's Pick