The Mystery of Fermi Bubbles
Scientists have been baffled by the giant pair of high-energy blobs sandwiching our Galaxy
There are so many unknowns in the vastness of the Cosmos. So much to explore. Add the ‘Fermi Bubbles’ to this list, named after the telescope that was used to observe them. These are giant space bubbles consisting of gas and cosmic rays that are sandwiching our Milky Way Galaxy (pictured above). They seem to be feeding off the black hole at the center of our galaxy.
Scientists have been trying to figure out the origins of this bizarre energy phenomenon since they were first discovered in 2010. The astronomers working with the Fermi Gamma-ray Space Telescope announced the discovery of the two giant blobs. The Fermi Telescope, launched on June 11, 2008, observes the cosmos using the highest-energy form of light.
In possession of new data, astronomers are now trying to make better sense of the Fermi bubbles as reported by Space.com. To make big balls of hot gas in space, you need a lot of energy, especially the ones that are spread over a distance of 25,000 light-years. The symmetry above and below our galactic center provides a strong clue that these energy bubbles may have some connection to the central supermassive black hole, known as Sagittarius A*.
Fermi bubbles are not visible to the naked eye as the gas inside them is really thin. The cosmic rays within the bubbles, which exist as high-energy particles, produce gamma rays — the highest-energy kind of light that exists.
Also, the cosmic rays can interact with each other to produce what’s called a neutrino — a particle with almost no mass, which can interact via the weak nuclear force in other particles. There is no proof, however, whether the neutrinos are being produced within the Fermi bubbles or coming from a distant part of the Universe.
There are numerous theories circulating on what is causing these massive energy blobs to exist.
- Maybe Sagittarius A* had a big meal — so big that it couldn’t digest it. The material might have energized with electric & magnetic forces beyond belief and managed to escape the event horizon of the black hole. The matter must have spread & thinned out while maintaining its energetic state to the present day.
- Or Perhaps a star came to close to the out black hole and hot shred in a violent episode releasing lots of gravitational energy.
- Or Maybe a cluster of stars went supernova at the same time, releasing massive amounts of energy that we saw engulfed in the Fermi bubbles.
A team of researchers has been sifting through the data to find a possible explanation using the High Altitude Water Cherenkov detector (a high tech ground-based gamma-ray telescope). Even after trying various experiments they could not reach a definitive conclusion with the available data.
In short, we still don’t know, how the Fermi bubbles were formed, how & why they are producing gamma-ray bursts & neutrinos. But with a few hypotheses ruled out and a new set of data may be will provide us a better clue to understanding the Fermi bubbles.