A mysterious object is sending out powerful radio signals from near the center of our galaxy. As reported by NewScientist, the pulses are coming from a spot just to one side of the galactic centre. Each pulse lasts about 10 minutes, and they repeat regularly every 77 minutes. If the source is near the centre of the Milky Way, it would be one of the most powerful emitters in the galaxy. The shape and timing of the pulses rules out most known sources, such as radio pulsars.
Milky Way Galaxy (Courtesy: NASA)
The team is currently studying the phenomenon using the Green Bank radio telescope in West Virginia, and also plan to use the orbiting Chandra X-Ray telescope to see if the object is also spewing X-Rays.
I have to stop here... my friends are calling again from the center of the galaxy...
Milky Way Galaxy (Courtesy: NASA)
The team is currently studying the phenomenon using the Green Bank radio telescope in West Virginia, and also plan to use the orbiting Chandra X-Ray telescope to see if the object is also spewing X-Rays.
I have to stop here... my friends are calling again from the center of the galaxy...
Galaxy Calling...
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he bursts coming from the new source, dubbed GCRT J1745-3009, each lasted about 10 minutes and repeated on a 77-minute cycle for nearly seven hours. In addition, the source is not stationary. "It [GCRT J1745-3009] has not been detected since 2002," Hyman notes, "nor is it present on earlier images."
Whatever it is, it is unique: the astronomers suggest it is either the first of a new type of object or an example of a known source acting in a novel way. Of interest to the scientists is the fact that no x-rays were detected along with the radio waves, because many astronomical sources emit both. In the future, the team plans to continue monitoring the Milky Way for further evidence of GCRT J1745-3009 using both radio and x-ray telescopes.
So there! Gotta be a beacon of some kind, wont you say?!
I think that is not really surprising. If the source is very close to the center, it has to orbit it at a very fast rate. The motion of the source relative to us should then be easily visible.
I would like to know the speed of the object, though. I am still looking for more details.. will let you know once I find anything :-).
An MJD of 52000 corresponds to JD = 2452000.5, which corresponds to March 31, 2001. The plot represents light curve (intensity of the light vs. time), so there was a spike in the apparent brightness of the object around March 31, 2001.
The interesting thing in the plot is the oscillations towards the end of the graph (which corresponds to a period of 100 days before Feb 28, 2005). That shows there is something new afoot in that object.
Nice picture
this year? It has only been two months! But I know what you mean :-D. Space is the last frontier, and discoveries are only going to get more frequent!
Which is a neutron star with massive amounts of electromagnetic energy...
Thats what I wrote!:
"the object could be a magnetar (a neutron star with a very powerful magnetic field)"
But magnetars emit strong x-rays, and little or no x-ray was detected here. Also, it seems the light curves do not match any other magnetars. perhaps a future chandra observation will clear the doubts.
The pattern of magnetic energy is influenced by the surface properties of the black hole -- which is a star, only one one which is unimaginably dense.
Black holes are known not to emit X-ray themselves, but the swirling storm of matter around them gets so furiously hot and moves so quickly -- typically a 3rd the speed of light -- that X-ray emissions are observed.
It has also been proposed that black holes do in fact emit radiation, which has since been called Hawkins Radiation, after Professor Stephen Hawking, who first proposed the idea.
So over time, a black hole would ultimately 'bleed' away into nothingness. However, this process would take a very long time.
So, maybe what they're looking at is a fading, dyeing black hole?
I'm sure Sray will fill out / pick holes with that idea...
The Hawking temperature of a 30 solar mass black hole is a tiny 2×10^(-9) Kelvin, and its Hawking luminosity a miserable 10^(-31) Watts. The black hole has to be really small to generate the amount of power seen with the object in this post... and then it would radiate so fast that it would vanish in a couple of years, and also follow a certain decay pattern. This object has been going steady for the last few years, and with no apparent pattern.
What if this was still a black hole, quite a small one -- as you've said -- but it's being fed dark matter?
Might we not see any radiation at all from the vortex of dark matter surrounding the black hole and then think the little devil was sat there all on its lonesome?
1. Inert matter, which are cold, and do not emit radiation and hence are invisible. Most extremely diffuse gas clouds (and brown dwarfs) fall in this category
2. Non-baryonic matter, like leptons etc.
3. Some new form of matter.
The first two kinds should get accelerated when drawn into the black hole, and should produce x-rays. It could be that some nearby star/mass is feeding this object, and so it is flaring up from time to time.
But if that is the case, it cannot be a evaporating black hole. If the radiation that is observed is mostly due to evaporation, it should blast out any matter stream that is coming from a disintegrating star nearby.
Now, it could be some new form of matter. That can only be said for certain once the chandra and other x-ray observatories produce their results on this object. Perhaps this form of matter does not produce x-rays while falling into the horizon.. only time will tell :-).
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