Images of the Milky Way – our home galaxy – typically show an immense, dusty band of stars. But we might have to revise the picture. That’s because, in November of 2010, a team led by Harvard astrophysicist Doug Finkbeiner discovered two giant, energy-filled bubbles extending from the galaxy’s center. He said each bubble is about a third of the size of the visible Milky Way. They contain high energy particles that produce gamma radiation.
Doug Finkbeiner Gamma radiation is very high energy light. These photons have about a billion times as much energy as visible light.
Dr. Finkbeiner’s team found these bubbles with the aid of NASA’s Fermi telescope. He said the bubbles have very distinct edges – in fact, put together, they look like a giant number “8” painted in the center of the galaxy.
Doug Finkbeiner: The edges are quite sharp compared to the overall structure, and so it looks to me like something that’s currently exploding, it looks like a shock wave propagating out from some burst of energy.
Finkbeiner said scientists are throwing around two ideas about how these bubbles formed. One is that the black hole at the center of our galaxy ‘burped’, spewing out light and electric particles at incredibly high speeds. Another idea is that a group of giant stars near the center of the Milky Way exploded all at once. EarthSky asked Dr. Finkbeiner how old these bubbles are.
Doug Finkbeiner: What seems clear is that they were caused by some huge energy injection at some point in the past. Whether they were caused one million or ten million years ago, we don’t know – some point in the past.
He said scientists haven’t spotted these bubbles before because they didn’t have the right telescope. The Fermi Telescope – which is floating out in space – specializes in gamma rays.
Doug Finkbeiner: Astrophysicists have been looking at Gamma Rays for years, decades, but the machinery gets better with each generation of course, and so this current Gamma ray telescope is about 100 times more powerful than it’s predecessor using this telescope is kind of like putting on your glasses for the first time.
He talked about the moment his team spotted the bubbles.
Doug Finkbeiner: Well there’s a great quote from Isaac Asimov which is that the sound of discovery is not “Eureka, I found it!’ but “Hmm, that looks funny!” And that’s really how it was! We were staring at the computer screen and said, “Hmm..that looks funny…is that really an edge?”
The edge of these bubbles, that is.
Doug Finkbeiner: It was a progressive thing. But there was a particular day when I went from thinking they weren’t real to thinking they were real. And that just had to do with looking at the data, getting more data – because the telescope is always getting more data – and analyzing it more carefully.
Finkbeiner and his team published their findings in November 2010 in The Astrophysical Journal.
EarthSky’s extended podcast, EarthSky22, features more on Doug Finkbeiner’s discovery
This is a very interesting phenomenon. Thank you so much for bringing it to us EarthSky!
What an incredibly fascinating phenomenon! I like the second possibility that a giant group of stars all exploded at once, however I’m now intrigued by what would cause them to all explode at once? And why the two energy bubbles form a giant number 8. Some associate this number with infinity and others as a lucky number for prosperity. It’s a bit controversial however I’d be interested in what holistic energy healers think about this!
Thank you EarthSky & Dr Finkbeiner!
Perhaps this has to do with the huge concentration of matter at the central bulge of the disc – we need to explore if other spiral galaxies also have this or not – could it be the missing matter that we’ve been looking for in the universe?
Why do you think the edges are so very sharp? It almost looks too perfect too symmetrically round for a random explosion…don’t you think? How can a group of giant stars explode so equally? What would cause a black hole to burp?
The picture of a figure 8 looks unbelievable…as if it were drawn so perfectly…
Sophia
Uhhmm, its not a picture. Its an artist conception. Sorry to disappoint you….
This is bizarre. I can see either explanation (I incline toward emission from the vicinity of the black hole) producing a jet of some kind, similar in appearance to emissions from planetary nebulae. These perfectly spherical, sharply bounded bubbles, however, imply some effect radiating from the centers of the bubbles, but they obviously came from the core. They appear to be independent of the galactic magnetic field, as well. This looks like something entirely new to astronomy.
Can Fermi obtain a spectrum we could derive an expansion rate and directions from? Composition maybe?
The more I look at the illustration, the more it looks like something compact was ejected from the core at top and bottom, proceeded for about 10 kpc to galactic north and south and then burst. Given the bubble radii and assuming an expansion velocity similar to supernova remnants, I’d place the start of expansion around 1 Mya. This is going to have a lot of astrophysicists scrambling for satellite time.
Somebody get an X-ray spectrum on this, please!
I just think it’s beautiful and wanted to say thanks for sharing the pictures. I don’t know very much about the science you study. I am not very good at basic chemistry, even… I study the human body as a medic for the Army.
I can only explain my awe for what you do with an example from my own life. I was explaining to a young soldier about the importance of getting up and walking around on a long airplane flight to prevent blood clots in the legs. I put it into a picture for him. His fascination for what I was explaining is the same for what you have shown us here.
Sorry for being so simple, but I really wanted to say thanks for the pictures.
Lydia
One last note. Anybody have a mechanism for the core black hole generating and propelling smaller black holes which evaporate by Hawking radiation and then produce an expanding shell, or something with similar effects?
Oh, BTW, NASA, point Fermi at all the Local Group spirals soonest, please.
Lydia’s right. THANKS!!! for the image.
Amazing. It just further confirms the awesomeness of Jehovah God, the creator of all things.
Are you suggesting that the workings of black holes is a ‘God’?
Larry,
You are sadly mistaken. After a telepathic prayer session with the Intergalactic Sage, I’ve learned this is clearly the work of Allah-Ra-Vishnu, not the two-bit pseudo-diety to which you refer.
Jim’s question about the expansion rate and his estimation using supernova velocities could indicate whether and how quickly this “shock wave” is moving through the galaxy and when it might pass through our outlying solar system. Perhaps this is more common behavior of black holes in spiral galaxies than we currently know so pointing Fermi at some others close by will be an interesting exploration. Great work NASA and Doug!
Sorry I didn’t weigh in earlier. Glad to see you guys love this. It’s awesome in the truest sense of the word, isn’t it?
In answer to a few queries…if memory serves (from my conversation with Dr. Finkbeiner), this kind of thing is common…in other words, lots of cool gamma ray formations in other galaxies.
- Beth
Thanks Beth. How about the expansion rate – is it something like Jim assumes based on supernova remnant velocities? Based on velocity are there any estimates if a “shock wave” is going to be passing through the solar system and when? Hopefully at least another million years! Keith
How is it possible to take this picture at this angle and at this distance?
Images of the galaxy have become rather common. They do it by turning a “whole sky” image of the Milky Way inside out with a computer. In the case of the image above, NASA also Photoshopped the dickens out of it. I downloaded the original paper via Finkbeiner’s faculty webpage at Harvard, and the images are much rougher. It runs to 46 pages, but I heartily recommend reading it. It it written very accessibly, and shouldn’t mystify any experienced amateur astronomer.
By the way, I withdraw some of my previous suggestions, because Fermi probably hasn’t the resolution to perform them.
is it definitely radiating out? Or could it have been round and getting sucked is making the middle collapse?
Read the NASA comments and Finkbeiner’s paper. It’s definitely radiating out, but the nearer it approaches the disk, the more material in the interstellar medium, fields, and flows from various sources will interfere with it. I give it around 100,000 years to get here. BTW, I’m sure this must have happened before, and Earth’s still here, so nobody panic, OK. By the time this news reaches the “inquiring minds” out there, it will likely be blown totally out of proportion, and someone will make a cool and totally inaccurate movie out of it.
This is strangely interesting, because the galactic core has been active for some time. However, the question to me is not “Why is this phenomenon appears to happen with active galactic core(s)?” But rather,”What is the Super massive black hole about to do? Because it’s for surely doing something that seems to be steadily building up to something spectacular and at the same time…unforgiving.
How is it building up? Whatever produced these bubbles occurred 1-10 mya. The x-ray flash in the 1950′s that we’ve detected the echo of was a mere belch caused by something falling into the hole, which probably happens frequently. I’m more worried by some relatively nearby supergiant like Eta Carinae or P Cygni or one we don’t know to watch yet going supernova on us without warning, like Sanduleak -69° 202a did in the LMG. That could give us a gamma sunburn for sure.
Hi There …well done on the discovery !
I have to agree with the black hole burp explanation ….
that sounds the most plausible to me !!!!
or maybe a burp fart even ? cos its going both ways ….
What the exact speed of outward expansion? Very interesting occurrence. Centre of Milky way requires our serious attention. Its impact on earth is a subject. Why earth gets so hot in June and July, when it is between Sun and Centre of Milky way and cold when hidden by Sun in December and January?
Does anyone have any comments on the whole 2012 event and how this particular find could present an unknown twist to the galactic lineup with the milky ways rift?
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