Scientists Speculate Milky Way ‘Bubbles’, a Black Hole ‘Belch’
Are the Milky Way gamma-ray-emitting bubbles capable of a gamma ray burst?
[Photo: NASA Images]
They’re described as ‘awe-inspiring’, two mysterious ‘bubbles’ scientists estimate are 50,000 light years miles across, the ‘exact distance halfway from the sun to the center of the Milky Way’. Other descriptions, if the bubbles were seen by the naked eye they would ‘stretch halfway across the sky’. The two ‘gamma ray emitting bubbles extend 25,000 light-years north and south of the galactic centre’.
The two bubbles detected by new technology.
CTV:
But the structures only became visible through the work of Fermi, the most sensitive and high resolution gamma-ray detector in existence. Gamma rays are the highest energy form of light.
The astronomers who discovered the structures sifted through the gamma-ray fog clouding the images until they were able to filter out the noise and the structures began to take shape before their eyes.
Scientists have two theories, the enormous black hole located in the center of the Milky Way–four million times the mass of the sun–’swallowed something big’ then ‘released a post meal energy burp’, or, the bubbles ‘were formed by a massive burst of star formation’ in the Milky Way.
The ‘money quote’:
“What we see are two gamma-ray-emitting bubbles that extend 25,000 light-years north and south of the galactic centre,” said Doug Finkbeiner, an astronomer at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., who first recognized the feature.
“We don’t fully understand their nature or origin.”
Gamma-ray-emitting bubbles which scientists don’t know their ‘nature’ or ‘origin’.
What does ‘their nature’ imply? Could the gamma-ray-emitting bubbles be capable of sending out a gamma ray burst? The type of gamma ray burst which, according to some theories, might wipe out the ozone layer and trigger a mass extinction? While we’re not postulating a potential ‘sky is falling’, or in this case, gamma-ray-emitting burst-mass extinction scenario, we are curious about the gamma-ray-emitting behavior of the newly discovered super-gigantic bubbles located in the center of our galaxy.
One line of research has investigated the consequences of Earth being hit by a beam of gamma rays from a nearby gamma ray burst. This is motivated by the efforts to explain mass extinctions on Earth and the probability of extraterrestrial life. The consensus seems to be that the damage that a gamma ray burst could do would be limited by its very short duration, but that a sufficiently close gamma ray burst could do serious damage to the atmosphere, perhaps wiping out the ozone layer and triggering a mass extinction. The damage from a gamma ray burst would probably be less than a supernova at the same distance.
Over at NASA, a tutorial on gamma ray bursts. What they are and the theory of the origin of a gamma ray burst. The key word, ‘theory’.
NASA:
The theory describing how gamma-ray bursts originate is called the “collapsar” model. Dr. Stan Woosley of the University of California, Santa Cruz, and one of the architects of the model, coined this term because the model involves the collapse of the core of a special kind of star. This core collapse occurs while the outer layers of the star explode in an especially energetic supernova dubbed a “hypernova” by astronomers. (Here we’ll refer to the theory as the “collapsar/hypernova” model to keep in mind both the core collapse and the supernova explosion.)
Highly informative, NASA’s ‘Lingering Mysteries’ section on gamma ray burst theory and new technology, i.e., NASA’s Swift Satellite.
NASA:
Although astronomers feel they have a good grasp on what triggers gamma-ray bursts with the collapsar/hypernova model, they know that many questions remain. To begin with, as we discussed at the outset, this model only deals with long-duration GRBs — those lasting more than 2 seconds and having an average duration of about 30 seconds — and that have a clearly defined burst followed by a clearly defined afterglow of progressively less energetic light. In 2003, the High Energy Transient Explorer 2 (HETE-2) began to see evidence of afterglows from short duration GRBs. But the afterglows in these initial studies were too short to determine a distance to these bursts. Furthermore, the properties of these short-duration bursts indicate that they appear to be triggered by a fundamentally different physical process, perhaps involving the merger of neutron stars. No one really knows. In addition, some GRBs are insufficiently energetic and fall into a category called “X-ray flashes” (XRFs). The BATSE instrument could not “see” these XRFs.
And,
On November 20th, 2004, NASA launched into orbit the Swift Gamma-Ray Burst Mission. The Swift satellite is NASA’s most sophisticated GRB-detecting satellite ever with sensitivity five times better than the BATSE. It also performs follow-through observations of the afterglow with X-ray and UV/optical telescopes. These are both automatically pointed to a burst location within a minute of a GRB being detected. The light from the afterglow is analyzed to look for the characteristic “light curves” of a supernova explosion.
The Swift mission joins HETE, RXTE, Integral, and the IPN array as the space-based side of the on-going, collaborative international effort by scientists on Earth to gain better understanding into gamma-ray bursts and what these titanic, distant explosions reveal about our awesome Universe.
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I love all these funny theories – how’s about the most obvious one, namely that our galactic core USED TO BE ACTIVE, and now it isnt – these bubbles are remnants of our core’s last feeding frenzy.
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The milky way galaxy bubbles are gamma ray lobes that are fundamentally self-similar to electron clouds shown photographed of a carbon atom at http://www.quantauniverse.com Cosmologist Robert Oldershaw explains discrete scale relativity, and the galaxy bubble lobes, by the electron wave function of the galaxy. Dark matter is not required for plasma scales.
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