A strange galaxy not far from us has a huge tail of 195,000 light years

Using the Subaru Telescope and the Canadian-French-Hawaiian CFHT Telescope, an international team of astronomers

observed an ultra-diffuse galaxy known as F8D1. During observations, scientists discovered a huge tidal stream from this galaxy.

Ultradiffuse galaxies (UDGs) are galaxies withextremely low density. The largest of them are similar in size to the Milky Way, but they contain only about 1% of the stars from our galaxy. The UDG mystery is still baffling scientists as they try to explain why these dim but large galaxies are so strange—not being torn apart by the tidal fields of their parent clusters. Previously, Hi-Tech talked about dark matter halos in galaxies of this type.

Galaxy F8D1 is the closest UDG to the Milky Way ingroup M81 (a group of galaxies in the constellations Ursa Major and Giraffe). It is about 12 million light-years away, with an effective radius of 8,150 light-years and a luminosity of about 40 million Suns.

RGB star count density in the HSC image.A giant tidal stream is visible emanating from F8D1, which is located on the southwestern edge. The flow is traced more than a degree to the northeast, towards NGC 2976 and M81. Credit: Zemaitis et al., 2022

Although F8D1 was discovered in 1998, in the past itstudied little. Now, a team of astronomers led by Rokas Žemaitis of the University of Edinburgh, UK, have used Subaru's Hyper Suprime-Cam (HSC) and MegaCam at CFHT to study this UDG.

During their observations, they discovered a giant streamstars that extends from F8D1 northwest towards the galaxies NGC 2976 and M81. This feature can be seen on both sides of NGC 2976. The flow bends about 0.8 arc minutes west of the main body at small radii and reverses direction at large radii, bending about 1.1 arc minutes to the east at a distance of 40 to 60 arc minutes. minutes. The tidal stream is at least 195,000 light years across.

Read more:

It turned out what happens to the human brain after one hour in the forest

It became known which tea destroys protein in the brain

Strange sea creatures in the depths of the ocean turned out to be similar to humans

Cover photo: NGC 4676. Source: NASA, H. Ford (JHU), G. Illingworth (UCSC/LO), M. Clampin (STScI), G. Hartig (STScI), ACS and ESA Science Team