A ‘Holy Grail’ of astronomy is to provide a clear map of our galaxy, a perspective of Earth’s relationship to the physical universe where our solar system moves between two spiral arms on its outer edges of the Milky Way, about 27,000 light years from His opaque central disk. Beyond that, like the maps of ancient seafaring navigators, there is a terra ingognito, the “avoidance zone” where no spacecraft have yet to travel beyond the opaque central disk.
Astronomers have now discovered a vast structure, the “South Pole Wall,” a cosmic curtain hidden behind billions of stars, dust, and dark worlds of the Milky Way in the “avoidance zone” that arcs across about 700 million light years along the southern border of the local cosmos.
Ghosts of the area
Lurking within the area is a huge ‘ghost’ galaxy, believed to be one of the oldest in the universe, was detected outside the Milky Way in November 2018 by a team of astronomers who discovered the object. massive when exploring new data from the European Space Agency’s Gaia satellite. One of the countless galaxies that cluster together in what is known as the cosmic lattice, huge strands of hydrogen gas in which galaxies are strung like pearls in a necklace that surrounds giants and dark hollow voids.
The image at the top of the page shows the South Pole Wall near the southernmost part of the sky. (© D. Pomarede, RB Tully, R. Graziani, H. Courtois, Y. Hoffman, J. Lezmy.)
The spectral object, named Antlia 2, avoided detection thanks to its extremely low density, as well as a perfect hiding place behind the dusty cover of the Milky Way disk with its concentration of bright, ancient stars near the galactic center. Optically, the Avoidance Zone is like “trying to look through a velvet cloth, black as black,” says Thomas Dame, Director of the Radio Telescope Data Center at the Harvard-Smithsonian Center for Astrophysics and Senior Radio Astronomer at the Smithsonian. Astrophysical Observatory in 2019. “In terms of tracing and understanding the spiral structure, essentially half of the Milky Way is terra incognito.”
“Huge Ghost Galaxy” – Hidden in the Milky Way ‘Avoidance Zone’
The new wall
An international team of astronomers, reports Dennis Overbye for the New York Times, led by Daniel Pomarède of Paris-Saclay University and R. Brent Tully of the University of Hawaii, announced this new addition to the local universe on Friday in an article in Astrophysical. Journal. , joining the previous discoveries of other structures of our universe like the Great Wall, the Great Wall Sloan, the Great Wall Hercules-Boreal Crown and the Void of Bootes. The document, based on measurements, made by Dr. Tully and his colleagues, of the distances of 18,000 galaxies up to 600 million light years, includes a video tour of the South Pole Wall.
“Monsters and dragons?” –Map the Terra Incognito on the Invisible Far Side of the Milky Way
You can’t see the galaxies on the wall, but Pomarède and her colleagues were able to observe its gravitational effects by gathering data from telescopes around the world. As a result, Overbye writes, “they discovered that the galaxies between Earth and the South Pole Wall are sailing away from us a little faster than they should be, at approximately 30 miles per second, being pulled outward by the massive mass of matter on the wall. And galaxies beyond the wall move out more slowly than they should be, held back by the gravitational pull of the wall. “
“One might wonder how such a large and not-so-distant structure went unnoticed,” Pomarède said in a statement issued by the Paris-Saclay University.
“Hyperion” – Titanic structure of Early Universe revealed: ‘Largest Proto-supercluster of galaxies ever found’
The discovery has come together with what astronomers call our “long direction,” Overbye writes: “We live on Earth, which is in the solar system, in the Milky Way galaxy.” The Milky Way is part of a small group of galaxies called the Local Group, which is on the edge of the Virgo group, a conglomerate of several thousand galaxies. “In 2014, Dr. Tully suggested that all of these features were connected, as part from a giant conglomerate he called Laniakea, Hawaiian for “open skies” or “huge sky.” It is made up of 100,000 galaxies spread over 500 million light years.
“We exist within a colossal sphere”: the vacuum that houses the Milky Way
But it seems that our direction does not stop there, in 2013, astronomers discovered that the Milky Way exists in a vacuum, one of the vast holes in the structure of the “Swiss cosmos” of the cosmos, with a radius of approximately 2 billion Light years. in diameter, the largest vacuum known to science, shaped like a sphere with a shell of increasing thickness formed by galaxies, stars and other baryonic matter. As with other voids, it is not completely empty, but it does contain our own galaxy, the Milky Way Galaxy (a few hundred million light-years from the center of the vacuum), the Local Group, and a large portion of the Laniakea Supercluster.
The Daily Galaxy, Max Goldberg, via Paris-Saclay University, New York Times and the University of Hawaii
