Astronomers have found a \u2018ghost galaxy\u2019 that is almost entirely\ncomposed of dark matter. The incredibly faint object lies about 300\nmillion light-years from Earth, within the Perseus galaxy cluster.<\/p>\n
The galaxy, named CDG-2, ranks among the most dark matter\u2013dominated\ngalaxies ever found. The discovery is reported in The Astrophysical\nJournal Letters.<\/p>\n
Unlike most galaxies that shine brightly due to billions of stars,\ngalaxies like CDG-2 are extremely dim and barely visible. This type of\ngalaxy is known as a low-surface-brightness galaxy.<\/p>\n
Such galaxies host relatively few stars, while most of their mass is\nthought to consist of dark matter\u2014the mysterious substance that does not\nemit, absorb, or reflect light.<\/p>\n
Instead of looking for light from the galaxy, researchers search for\npatterns of globular clusters.<\/p>\n
A globular cluster is a densely packed, spherical collection of stars\nthat typically orbits a large galaxy. The presence of such clusters can\nindicate an unseen galaxy in the vicinity.<\/p>\n
Using sophisticated statistical methods, the Li team scanned\nastronomical data to search for groups of globular clusters that are\nunusually close together.<\/p>\n
This approach successfully identified ten previously known, faint\ngalaxies and two new galaxy candidates that are likely dark\ngalaxies.<\/p>\n
High-resolution images from the Hubble Space Telescope reveal four\nglobular clusters clustered tightly within the Perseus cluster.<\/p>\n
When data from Hubble, Euclid, and Subaru are combined, researchers\ndetect extremely faint light extending around the cluster of globulars.\nThis diffuse light provides evidence that a hidden galaxy lies\nbeneath.<\/p>\n
David Li explained the significance of the finding. \u2018This is the\nfirst galaxy detected solely through its globular cluster population,\u2019\nLi said.<\/p>\n
\u2018Conservatively, these four clusters are likely the entire globular\ncluster system of CDG-2.\u2019<\/p>", "url": "https:\/\/jawawa.id\/newsitem\/astronomers-discover-a-ghost-galaxy-containing-99-dark-matter-1772723789", "image": "" }, "sponsor": "Okusi Associates", "sponsor_url": "https:\/\/okusiassociates.com" }