Milky Way Galaxy

In 2010, astronomers working with the Fermi Gamma-Ray Space Telescope unveiled a previously unseen structure centered in the Milky Way that spans 50,000 light-years that may be the remnant of an eruption from the supermassive black hole at the center of our galaxy. The structure spans more than half of the visible sky, a region roughly as large as the Milky Way itself, and it may be millions of years old, its origin an unsolved mystery.

In 2012, The Galaxy reported that scientists were conducting more analyses to better understand how the never-before-seen structure was formed. The bubble emissions are much more energetic than the gamma-ray fog seen elsewhere in the Milky Way. The bubbles also appear to have well-defined edges. The structure’s shape and emissions suggest it was formed as a result of a large and relatively rapid energy release – the source of which remains a mystery.

Remnants of a Supersized Black Hole Eruption? Massive Bubbles Extend from Milky Way Center for 50,000 Light Years (Today’s Most Popular)

The nature of Fermi bubbles is still unclear, however the location of these objects indicates their connection to past or present activity in the center of the galaxy, where our central Sag A* black hole of 106 solar masses is located. Modern models link the bubbles to star formation and/or an energy release in the Galactic center as a result of tidal disruption of stars during their accretion onto Sag A*. The bubbles are not considered to be unique phenomena observed only in the Milky Way and similar structures can be detected in other galactic systems with active nuclei.

Fermi bubbles promise to reveal deep secrets about the structure and history of our galaxy. We don’t know why the mass of the black hole in the center of the Milky Way is so small relative to other supermassive black holes, or how the interaction between this relatively small black hole and the Milky Way galaxy works. The bubbles provide a unique link for both how the black hole grew and how the energy injection from the black hole accretion process impacted the Milky Way as a whole.

Gigantic Bubbles at Center of Milky Way Reaching Out 50,000 Light Years Discovered to be Source of Mysterious Cosmic Rays

In August of 2017, The Galaxy reported that a team of scientists from Russia and China developed a model which explains the nature of high-energy cosmic rays (CRs) in our Galaxy. These CRs have energies exceeding those produced by supernova explosions by one or two orders of magnitude. The model focuses on the discovery of the giant structures called Fermi bubbles.

Fermi Bubbles

Hints of the Fermi bubbles’ edges shown above were first observed in X-rays by ROSAT, which operated in the 1990s. The gamma rays mapped by the Fermi Gamma-ray Space Telescope extend much farther from the galaxy’s plane.

One of the key problems in the theory of the origin of cosmic rays (high-energy protons and atomic nuclei) is their acceleration mechanism. The issue was addressed in the 1960s when scientists suggested that CRs are generated during supernova (SN) explosions in the Milky Way. A specific mechanism of charged particle acceleration by SN shock waves was proposed in

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