Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: evan_au on 07/02/2021 03:30:28
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On South African phone-in radio this week, Dr Chris Smith was asked a question about giant bubbles extending above and below the disk of the Milky Way galaxy. The caller could not provide any more information, leaving the question open.
I am wondering if the caller was referring to the "Fermi Bubbles", which were discovered in 2010 by a space Gamma-Ray telescope?
- These do extend above and below the plane of the Milky Way galaxy, by about 25,000 light-years (about the same distance as between the Sun and the center of the Milky Way)
- There have been tantalizing reports from the Ice Cube neutrino telescope of unusually high-energy neutrinos coming from the general direction of the Fermi bubbles
- A more recent paper presented in mid 2020 claimed that astronomers have now been able to detect these Fermi Bubbles in visible light, which will provide far higher resolution measurements of velocity (via Doppler shift) than you can get with a Gamma-Ray telescope
Many radio galaxies had previously been observed, with elongated sources of radio emission extending from the center of the galaxy.
- This could be a polar jet emitted as a "burp" from the supermassive black hole at the center of the galaxy, after it had an oversized meal
- The Milky Way's supermassive black hole is currently rather quiet, but the presence of these Fermi Bubbles suggests that perhaps it was more active in the past, blowing large amounts of matter into space?
See: https://www.sciencedaily.com/releases/2020/06/200603120542.htm
Images: https://commons.wikimedia.org/wiki/Category:Fermi_Bubbles
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It deserves a picture Evan
(https://cdn.mos.cms.futurecdn.net/7kmmPgNZM7s9p4uS2xxVNB-1024-80.jpg.webp)
From
https://www.space.com/fermi-bubbles-milky-way-radiation-mystery.html
Very interesting.