Skip to comments.The Mystery of the Intergalactic Radio Bursts
Posted on 07/06/2013 4:54:09 AM PDT by NYer
Its a recurring theme in astronomy: observers see a blast of energy out in the cosmos, scratch their heads in confusion for a while, and finally uncover the existence of something entirely surprising and new. It happened with the quasars (now known to be gigantic burps from black holes swallowing hot gas), the pulsars (fast-spinning neutron stars sending out blips of radio noise hundreds of times every second), and even the Big Bang itself, first seen as a stream of microwaves slamming into Earth from all directions, nearly 14 billion years after the event itself.
Now it may be happening again. Back in 2007, astronomers detected a burst of radio noise, lasting maybe a second or so, the cause of which was totally unclear. There was reason to suspect it came from beyond the Milky Way, and must be extremely powerful to be visible at all. But it never repeated, and neither did a second, similar blast seen in 2011, making it very tough to puzzle out what was going on. Maybe both events were just some sort of rare fluke.
But a new paper in Science makes that seem very unlikely. Using the giant Parkes radio telescope in Australia, astronomers have recorded four more of these mysterious bursts, and when the scientists extrapolated across the entire sky, they concluded that perhaps 10,000 of these blasts are popping off every day, all over the heavens. Its still a mystery what they are, says lead author Dan Thornton, of the University of Manchester, in the U.K. But at least its not a mystery that they exist. In fact, Thornton and his co-authors claim that the observations reveal what he calls a new cosmological population of energy blasts, whose true nature is unknown.
(Excerpt) Read more at science.time.com ...
Illustration showing the absorbance of electromagnetic waves by the Earth's atmosphere.
Michael D. Lemonick
Senior Science Writer
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Mr. Lemonick covered science and the environment for TIME magazine for nearly 21 years, where he wrote more than 50 cover stories, and has also written for Discover, Scientific American, Wired, New Scientist and The Washington Post. Lemonick is the author of four books, and a cover story for TIME was featured in the anthology Best American Science and Nature Writing 2007. He has taught science and environmental journalism at Princeton, Columbia, Johns Hopkins and New York Universities.
Nice picture, thanks. I think the word you are looking for is “absorption” or maybe attenuation.
The interaction of radio waves with the atmosphere is highly dependent on angle of incidence, rainfall and time of day. For instance, during daylight hours, AM radio waves are absorbed in the stratosphere, making AM daytime radio a local medium. At night when the stratosphere deionizes, AM radio zips right through the stratosphere, to ionosphere, which looks like a highly polished mirror to AM and signals can travel half way round the globe. (WBZ-AM 1030 Boston has been received in New Zealand, for instance.)
Anyway, believe it or not, it’s more complicated than that simple picture.
Also, the above-referenced article states that the bursts have a wavelength of about 1 meter (300 MHz) and have been observed to repeat at intervals of 77 minutes.
There are hundreds of millions of galaxies and billions of planets. That is an immensity that is beyond the conceptual concept of most people. It is logical to assume that the universe teems with life. Yet given the huge distances separating these platelets and the laws of physics, it is simply not possible for an alien biological or a mechanical entity to visit. However Earth has been transmitting huge amounts of digital alogarithmic data for the past twenty five years. It is not inconceivable that within the next twenty some computer on earth will receive a truly wondrous communication.
IOW, he’s a dilettante, like Al Gore. The article was mildly provocative, but not particularly informative. He does give the impression of not really understanding what he is talking about.
Yes. And decadence is a place of sin.
The decadent do not even believe that there is such a thing as sin, so lost are they.
Except for the single irrefutable fact that there is no evidence that life exists anywhere except earth. Not a single piece of data.
Now I GET that our ability to search for life is limited by technology to a certain sphere but that doesn't change the fact that we have no evidence for life anywhere else.
Doesn't seem to be the same phenomenon. The article is dated prior to the discovery of the sources in the Time article and refers to sources in the center of the Milky Way, not extra galactic sources.
The article did not say that the sources were "broadband", but occurred over a very large bandwidth. I take that to mean that any single source is coherent, i.e., narrowband, but the population includes sources at various wavelengths. (For objects within the Milky Was, it is unlikely that Doppler shift could cause very large Doppler shifts.)
...Its a super-galactic submarine single ping alert.
I should not have paraphrased material from the article I referenced. Here is the exact quote:
One important clue to understanding the origin of the radio bursts is that the emission appears to be coherent, Hyman said. There are very few classes of coherent emitters in the universe. Natural astronomical masers the analog of laser emission at microwave wavelengths are one class of coherent sources, but these emit in specific wavelengths. In contrast, the new transients bursts were detected over a relatively large bandwidth.
The "Hyman" referenced here is Dr. Scott Hyman, professor of physics at Sweet Briar College.
I would just say - in my own defense - that I can't figure out how they could have detected "coherence" without getting fairly high-res spectral information from the signals.
If a signal has a relative bandwidth of 1% I’d call it coherent. It could have a lot of noise modulation, or whatever, but that’s still coherent to me. Good commercial RF sources have RMS bandwidths in parts per trillion, but for a natural source to exhibit 1% relative bandwidth is provocative.
Your theory has no real basis because it is impossible to know what we don’t know. That is especially true if 99.9% of human knowledge is excluded
I accept your reasoning.
To me, having been raised in the age of lasers (I was in kindergarten when Ted Maiman announced his sensational ruby laser) I've always thought of "coherence" as being something involving parts-per-million stability.
I can see how, when one considers galactic distance and time scales, that is an unrealistic standard.
If nothing else, relative bandwidths on the order of 1% indicate a very high "Q" somewhere in the transmission chain. High "Q" in turn indicates that large amounts of electro-magnetic energy are being stored somewhere, somehow.
At least, E-M energy storage is the only cause I can think of that doesn't definitely involve intelligent design.
Absorbance is indeed what is illustrated. It is the quality of optical density - absorption and attenuation are verbs relating to the process of absorbance.
Of course, the Milky Way, vast as it is, is only one of hundreds of billions of galaxies that are known to be out there...so far.
No doubt that there are many other planets teeming with life out there, some more primitive by Earth standards, others way more advanced. Even the ones that are far more advanced will probably never develop the technologies to make contact with this little outpost called Earth.
Yes, I agree.
But look at the length of time he has been making a living writing about things he does not understand. Amazing.
But also remember, this is TIME magazine, the people who put “We are all Socialists Now” on the cover.
It Is All Illusion.
Mine is Black!
I tried to write a short story once. The characters were an entomologist grad student with an interest in interstellar communication, her boy friend in far off Australia who ran the big telescope array, and a bee, the worker supervisor that delegated task in the colonial hive.
The gist was the grad student was so interested in her career and minding the apiary of her mentor she would not succumb to her own biology and go to Australia and true love. Meanwhile in the colony, growth necessitated action. A decision was being made to reproduce the colony and swarm. This action required tremendous communication between tens of thousands of individuals.
The irony was the forlorn grad student was so intent on communications from space she overlooked the active communication in process literally at her fingertips, among the bees on the frames she was removing and studying.
If we can not communicate or understand the communications of the earthbound colonies of bees, there is virtually no hope of understanding extraterrestrials.
Except they aren’t verbs, they are nouns. Hey - I didn’t major in English...
It’s Only Rock ‘N’ Roll (But I Like It)...
“...a stream of microwaves slamming into Earth...”
I’m neither a physicist nor an electromagnetic engineer but IIRC, the radiation of which he speaks is the 3 degree Kelvin attributed to the Big Bang.
While it is traveling at 300,000km/sec like everything else in the spectrum, I can’t picture radiation from 3K as having the energy to be called “slamming”.
Can anyone enlighten me?
It's a very subtle sort of slamming.
Your comment applies equally to the opposite theory.
Cosmic microwave radiation is wideband and very low level and nearly completely isotropic, coming in from all directions. This is a booming loud signal by comparison, at a wavelength 100X longer than the peak of cosmic microwave and coming in from a single direction.
Cosmic microwave radiation slams as well as any radiation source. The “temperature” refers to source temperature of an equivalent black body source. There is a theoretical model of what black body radiation looks like, and laboratory sources match it quite well. The Universe also matches the model, if the current temperature of the Universe is 2.7 K. See: http://en.wikipedia.org/wiki/Cosmic_microwave_background_radiation
>>”No doubt that there are many other planets teeming with life out there, some more primitive by Earth standards, others way more advanced. Even the ones that are far more advanced will probably never develop the technologies to make contact with this little outpost called Earth.”<<
You are wrong (wink..) Aliens actually find “Planet Earth” to be an interesting place for interaction despite our relative obscurity in the universe.
Theme from “Flash Gordon”:
“Yet given the huge distances separating these platelets and the laws of physics, it is simply not possible for an alien biological or a mechanical entity to visit.” IF you limit your Physics to the point of declaring that we now have all the knowledge we will ever have regarding life, luminal speed, and dimensional reality, then your bold assertion is true. BUT I don’t believe you are in possession of all there is to know.
What I do not understand is this: 3K is by definition a very, very low energy state. Thus, how can we say that this low energy state “slams”?
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