A new map of the sky at the outer ends of the Milky Way

Using data from NASA and ESA (European Space Agency) telescopes, astronomers have released a new map in the entire sky of the most distant part of our galaxy, known as the galactic halo. According to scientists, the region may contain a massive reservoir of dark matter, a mysterious and invisible substance that is thought to make up the bulk of all mass in space.

A feature of the new map is the vigil of the stars, prompted by a small galaxy that will crash into the Milky Way.

The map reveals how a small galaxy called the Large Magellanic Cloud (LMC) navigated the Milky Way galactic halo like a ship through water. Its gravity creates an awakening in the stars behind it. Observation on a new stellar map is thought to be the outline of this passage of dark matter; the stars are like leaves on the surface of this invisible ocean, whose position changes with dark matter.

This is Dad’s first map to offer a similar picture of the outer regions of the halo, where the vigil is located – about 200,000 light-years to 325,000 light-years from the galactic center. A previous study indicated the existence of a vigil, but a map of the sky confirms its presence and offers a detailed view of its shape, size and location.

The halo disorder offers astronomers a unique opportunity to study dark matter. Despite the fact that dark matter does not emit / repel / absorb inflammation, the gravitational influence of dark matter has been observed across the universe.

Images of the Milky Way and the Great Magellanic Cloud (LMC) are overlaid on a map of the surrounding galactic halo. A smaller structure is a being created by the movement of the LMC through this area. The larger light blue characteristic corresponds to the high density of stars observed in the northern hemisphere of our galaxy.
Credit: NASA / ESA / JPL-Caltech / Conroy et. al. 2021

Various studies suggest that the interaction between dark matter and the Large Magellanic Cloud affects our galaxy. The LMC orbits the Milky Way. Because of this orbit, the gravity of dark matter pulls on the LMC and slows down, causing the rotation of the dwarf galaxy to become smaller and smaller until the galaxy finally collides with the Milky Way in about 2 billion years.

Rohan Naidu, a doctoral student in astronomy at Harvard University and co-author of the new paper, said, “This robbery of the energy of a smaller galaxy is not only the reason why the LMC merges with the Milky Way, but also why all galaxy mergers happen. Waking up on our map is really a good confirmation that our basic picture of how galaxies merge is in place! “

Charlie Conroy, a professor at Harvard University and an astronomer at the Center for Astrophysics The Harvard & Smithsonian, which co-authored the study, said, “You can imagine that the vigil behind the boat will be different if you sail through water or honey. In this case, the properties of awakening are determined by which theory of dark matter we apply. “

Nicolás Garavito-Camargo, a doctoral student in astronomy at the University of Arizona, who led the work on the model used in the paper, said, “Confirmation of our theoretical prediction by observational data tells us that our understanding of the interaction between these two galaxies, including dark matter, is well on its way.”

Gurtina Besla, co-author of the study and associate professor at the University of Arizona, said, “It’s really a special set of circumstances that came together to create this scenario that allows us to test our theories of dark matter. But we can only accomplish this test by combining this new map and the dark matter simulations we made. “