Recently we looked at Fast Radio Bursts (FRBs) and the ongoing effort to identify their source (see Fast Radio Bursts: SETI Implications?) Publication of that piece brought a call from my friend James Benford, a plasma physicist who is CEO of Microwave Sciences. Jim noticed that the article also talked about a different kind of signal dubbed ‘perytons,’ analyzed in a 2011 paper by Burke-Spolaor and colleagues. Detected at the Parkes radio telescope, as were all but one of the FRBs, perytons remain a mystery. As described in the essay below, Jim’s recent trip to Australia gave him the opportunity to discuss the peryton question with key players in the radio astronomy community there. He has a theory about what causes these odd signals that is a bit closer to home than some of our speculations on the separate Fast Radio Burst question, and as he explains, we’ll soon know one way or another if he’s right.
by James Benford
A few weeks ago I visited Swinburne University in Melbourne Australia. I was invited there to give a public address about the controversy surrounding METI (Messaging to Extraterrestrial Intelligence). I also visited the radio astronomy group and discussed how to search for an explanation for the Perytons, dispersed swept-frequency signals. My host was Ian Morrison. I also spoke for several hours with Emily Petroff, Willem van Straten and Matthew Bailes, the head of the group.
Ian had sent me the Burke-Spolaor paper before I arrived, so I knew what the basic observations were. In our discussions, I learned that there have been other observations of Perytons and that they have the same general features: They occur from one portion of the sky (which is a clue), happen around midday, and peak in the southern hemisphere’s winter around July (another clue). The shape of the frequency versus time curve is not quite the same as true dispersion measure (DM) signals. There are kinks and dropouts in the frequency-time graph. And the shape is a bit off of the standard DM scaling, 1/f2. And they always occur at the same frequency, about 1.4 GHz.
Although they had concluded in the 2011 Burke-Spolaor paper that signals came from the horizon and were not local to the Parkes radio telescope site, they are now beginning to think that it might be emission from some local electronics. Since they knew of my knowledge of microwave sources, they asked me whether or not whether microwave ovens could be an explanation.
I had already concluded that it was a likely explanation because microwave ovens are highly nonlinear devices and can produce several frequencies. They are designed to stay on a single frequency, 2.45 GHz, but can oscillate at a variety of frequencies. If the magnetron voltage changes, other oscillation modes, with lower frequencies, will occur.
Although microwave ovens when they leave the factory have Faraday shields around them and do not radiate into the environment, over time these precautions can fail due to wear on the equipment. The primary means of preventing radiation from an oven into kitchens is redundant safety interlocks, which remove power from the magnetron if the door is opened. Microwaves generated in microwave ovens cease once the electrical power is turned off.
Image: The Parkes Visitor Centre with the 65-m dish in the background. Credit: Jim Benford.
After describing magnetrons in some detail I offered a hypothesis that leakage of microwaves was occurring from the magnetron, which generates them, and then leak from the enclosing metallic cabinet. They can easily develop separations between the metal case that the microwave magnetron is in and also in the outer case, of which the door is a part. The door is the weakest part of the shield.
Microwave ovens operate at a single frequency and are not dispersed, as their Peryton signals are. But magnetrons sometimes fail to produce a single frequency, due to mechanical disturbances or changing electrical characteristics.
Conditions change in the magnetron when it is turning on or turning off. The voltage on the cathode rises at the turn on and falls at the turn off. That changes the resonance condition and thus excites different oscillation modes, with lower frequencies. This ‘mode hopping’ may explain the observed Perytons fall in frequency.
People simply opening the door, interrupting operation, could well cause this odd radiation. Yanking the door open shuts down the voltage on the cathode of the magnetron, but the electron cloud in the resonator takes a short time to collapse because the cathode is still hot, and still can emit electrons as the voltage falls. Therefore the magnetron will continue to resonate until both the voltage goes to zero and the cathode cools down.
A microwave oven doesn’t cease to radiate instantly when the electricity drops off. The timescale for the cessation is not well documented. It’s a contest between the L/R timescale of the electrical circuit and the cooling of the cathode. The Peryton signals last a few tenths of a second, which could be consistent with the fall time of the voltage and the time for the electron cloud to collapse. The frequency shifts as the voltage falls because a resonant condition, which depends on the ratio of applied voltage to insulating magnetic field (V/B), is changing. (The magnetic field doesn’t change because it’s produced by a permanent magnet.) V/B is proportional to the circulation speed of electrons in the cavity of the magnetron, which relates to the resonant frequency of the device. (For more on magnetron operation, see High Power Microwaves, Second Edition, Benford, Swegle & Schamiloglu, Taylor & Francis, 2007).
Image: Microwave magnetron from a microwave oven. Credit: Jim Benford.
I was thinking that the radio telescope at Parkes looks at a small part of the sky. But it also has side lobes through which the telescope is less sensitive to signals at other angles. The most important of these is the back lobe exactly opposite to the direction in which the telescope is pointing. This occurs because any source directly behind the dish radiating signals will diffract around the edge of the dish. This diffracted signal will arrive coherently at the receiver at the focal point of the dish.
So I inquired as to what was directly behind the dish when it was pointed at the Peryton location. They said it was the Visitor Center.
I realized at once that the Visitor Center was the microwave oven location that would have the most use and fitted all the clues. That use would occur primarily in the midday. And that in the southern hemisphere winter, more people would visit Parkes in the outback.
So I made a prediction: That they would find that the Perytons were coming from the microwave oven in the Visitor Center. I suggested the Swinburne researchers could check on that by several tests:
1) The simplest thing would be to simply remove the old oven and replace it with a new one. The Perytons would cease. But that would require taking a lot of data over time to see if they had really disappeared since Perytons are infrequent phenomena.
2) They could replace all ovens with a non-microwave cooker. That’s also a slow approach.
3) A more aggressive approach would be to rewire the oven, to defeat the safety interlocks and turn the oven on, allowing it to radiate directly into the Visitor Center. Then the signal should be quite evident and they would see a lot of Perytons. Turning the oven off and on would prove it to be the source. (Of course one would evacuate people and whoever turns the oven on would need to be behind a conducting radiation shield.)
I hear the Swinburne team is going to conduct such experiments. I hope they get a clear result. If my hypothesis is proved true, it may call into question whether the famous Lorimer Burst of 2001 was in fact a Peryton. If so, it was not extragalactic, as its large DM was taken to mean.
Perhaps we shall soon know the origin of these mysterious signals.
The Burke-Spolaor paper on perytons is “Radio Bursts with Extragalactic Spectral Characteristics Show Terrestrial Origins,” Astrophysical Journal Vol. 727, No. 1 (2011), 18 (abstract). The paper on the ‘Lorimer Burst’ is Lorimer et al., “A Bright Millisecond Radio Burst of Extragalactic Origin,” Science Vol. 318 no. 5851 (2 November 2007), pp. 777-780 (abstract).
Another mystery solved – perytons are products of a technological civilisation… us!
A further implication, if this idea is right, lies in the entire, growing field of transient radio astronomy.
We have a vast microwave network all around us. Our cell phones are not powerful but they turn on and off the stronger transmitters and antennas of the cell phone towers. Add to that the many internet hubs and radars and general communication webs, especially around airports.
All these may have fast transients of largely unreported features. Radio astronomers had best study the transient background in detail, to eliminate false positives in our search for unusual astrophysical events, and especially for the beacons I and Jim and Dominic Benford have explored in earlier papers.
This could be a bit tedious, but it’s essential. If it’s any consolation, any transmitting aliens hailing us will have considered this as well.
A very good explanatory article with the tests proposed to confirm or falsify ghe hypothesis. I hope we hear about the results of the experiment.
At least we will know if a microwave oven is coming our way. The best place currently to remove as much noise as possible is to place radio or other types of detectors on the far side of the moon. However as we put more and more craft into space I am afraid it is going to get noisier and noisier and harder to detect the very faint technology signals.
@Michael,
I recall seeing Frank Drake advocate moving radio SETI to the far side of Luna in circa 1990 due to exactly this concern. Of course, back then we thought CATS (cheap access to space) via fully reusable single stage to orbit boosters was just around the corner. Building another Arecibo or a large radio telescope array on the lunar far side did not seem out of the question. It still is not a bad idea. The lunar dust is not a problem for radio astronomy, craters are abundant, and the low gravity reduces the mass of materials required to construct radio dishes. Perhaps if SpaceX can succeed in using the Falcon heavy (triple core) as a reusable flyback first stage, some of these old dreams could be realised.
Out on a limb here, but don’t some radio telescope designs include additional small antennas to detect local interference? Or is the signal from a microwave so weak that only the dish itself would pick it up?
Possibility L and/or S band vegetation sensing satellite signals with harmonics. The type of orbit would have an effect on the number of detection signals due to chance alignment.
http://www.whrc.org/education/rwanda/pdf/Walker_SAR_Veg_Mapping.pdf
A satellite like this one,
https://directory.eoportal.org/web/eoportal/satellite-missions/j/jers-1
but which one?
What about the milli-second timekeeping of the device over the course of 5 years? I have reviewed the peryton literature, and this is a phenomenon which requires a precise clock in the device. Does this particular microwave in the visitor centre have a sync’ed clock, e.g. to GPS, radio, or the powerline?
Remember that the perytons occured at .8 to the integer second over 5 years.
and at least that would make them better cooks, falsifying notwithstanding …
Interesting suggestion. I have a few possible problems, ranging from mild to serious.
1) Is the back lobe of the Parkes dish as strong as you’ve assumed?
Anecdotally, I can confirm that the sidelobe strength behind the dish (out of view of the focus cabin) is much weaker than in front of the dish. This is from a test in which I walked around the outside of the dish with a sparking barbecue lighter – but I didn’t try standing directly behind the dish, so I didn’t test the back lobe itself. On theoretical grounds: for the diffracted signal from a source directly behind the dish to arrive in phase at the receiver, the rim of the dish must be perfectly circular, to within about a centimetre … but in the absence of actual test data, I’ll agree this point is plausible.
2) The perytons were detected at the wrong azimuth for the visitors’ centre to be in the back lobe.
The majority of perytons detected with Parkes were at an azimuth of ~137 deg. (See table 6.1 of Burke-Spolaor’s thesis [1].) At that azimuth, the rear sidelobe should be pointing northwest from the dish. The visitors’ centre, however, is directly west of the dish. (See map [2]. The microwave is presumably in the cafe, which is the smaller structure on the northeast side of the building to the west of the dish.) Offices and engineering workshops, however, do lie to the northwest.
3) The perytons were detected at the wrong elevation for the back lobe to intersect any nearby buildings.
The same set of perytons was detected at a zenith angle of ~33 deg; i.e. the telescope was pointing ~33 deg away from the vertical on this azimuth. The zenith angle limit of the Parkes dish, at which the dish can depress no further because its lower edge contacts the ground, is 60 deg, and its diameter is 64 metres. A little trigonometry tells me that this means the centre of the dish is at a height of 27.7 metres, and a little more tells me that, when the dish is pointing at a zenith angle of 33 deg, the rear axis of the dish would intersect the ground 18.0 metres horizontally from the centre of the telescope. This point is, in fact, underneath the dish when it is in its stowed, horizontal state. It is certainly closer than the distance from the telescope to the closest building, which is ~70 metres; even when the dish is pointed as low as it can go, the rear lobe will not be this far from the telescope on the ground.
We can therefore, I think, rule out the possibility that perytons are detected through the rear lobe *and* they originate from a microwave (or anything else) in a nearby building. Either of those possibilities on its own, however, is still possible.
4) Not all of the perytons were detected at the same point on the sky.
Some of the perytons (#13-15 in the table) were detected at wildly different points on the sky. If these originate from the same mechanism as #1-12, that mechanism cannot rely on a fixed geometry.
5) Perytons have possibly been detected with a telescope other than Parkes.
Saint-Hilaire et al. [3] report the detection of five peryton-like events with the Bleien Radio Observatory. Of course, they might have a microwave on site too.
Naturally, none of these objections matter if we see an increase/decrease in the rate of perytons after taking one of your suggestions for changing the microwave setup in the visitors’ centre. (Another possibility would be to add a mechanism to automatically log the use of the microwave, and compare this log with the times of detected perytons.) Experimental results trump any amount of theorising.
Ultimately, though, I suspect that perytons may only be properly understood when they are detected simultaneously with multiple antennas (as NS suggested), so we can triangulate to find their position of origin in the near- or far-field.
P.S. A quick caveat: I’m a radio astronomer, but this isn’t quite my area, so I’m not necessarily current on the literature: there may be a critical reference or two that I’ve missed.
[1] http://researchbank.swinburne.edu.au.zedataro.com/vital/access/services/Download/swin:22855/SOURCE3
[2] https://www.google.co.uk/maps/place/CSIRO+Parkes+Radio+Telescope/@-32.9985403,148.2633869,234m/data=!3m1!1e3!4m2!3m1!1s0x6b1aac1361ee4109:0xc6cbb19c660be153?hl=en
[3] http://arxiv.org/abs/1402.0664
Justin, although this is a outside my own area I can offer a few comments on what you’ve written. Whether it’s useful or not…?
“1)…Anecdotally, I can confirm that the sidelobe strength behind the dish (out of view of the focus cabin) is much weaker than in front of the dish.”
This is not strictly speaking a side lobe. The antenna (probably a horn?) is at the parabola’s focus, so if you are behind the dish you are in the main lobe of the antenna. It is then a matter of the attenuation of the dish itself to 1.5 GHz. Even if -100 db I am sure an oven will be received loud and clear! I’ve measured microwave transmittal through (and around) metal meshes and thin films and have been amazed at times by how much gets through.
“3) The perytons were detected at the wrong elevation for the back lobe to intersect any nearby buildings.”
That’s potentially interesting. RF at 1.5 GHZ will diffusely reflect off most building materials. There will of course be reflection attenuation, but these are potentially strong local signals and they could be seen to come from almost any surface.
“2) The perytons were detected at the wrong azimuth for the visitors’ centre to be in the back lobe.”
See my previous comment. I’ll also add here I doubt diffraction around the dish rim is a likely culprit since the angle required is very high to reach the antenna. More likely in this situation are the minor lobes of the antenna (again, horn?) may be able to directly “see” sources away from the dish. Illumination of the dish is never 100%.
“4) Not all of the perytons were detected at the same point on the sky.”
Unless you do fancy processing with signals from at least one more antenna (see NS’s comment) all you know is that a signal was received, and not which lobe, reflection, diffraction, etc is responsible. It is however tempting to assume it’s the main lobe in combination with the dish (i.e. where the dish is pointing at the sky).
“5) Perytons have possibly been detected with a telescope other than Parkes…Of course, they might have a microwave on site too.”
Heh!
Ron, this is really quite interesting to see how our fields intersect. I suspect that I may have caused a bit of confusion, though, by using jargon that we don’t have in common. In astronomy, we typically refer to the main collector – in this case, the 64-metre parabolic reflector – as an antenna, and we refer to the antenna at the focus of the parabola as the “feed”. When we talk about the primary beam and the side lobes, we’re usually referring to the beam pattern of the entire assembly. Jim Benford, in the article above, was apparently using this convention when he referred to the ‘back lobe’, behind the dish.
A bit about the Parkes telescope might be helpful to know here. It has a range of receivers which can be swapped in and out of the focus cabin, for astronomy at different frequencies. The feeds of these receivers are generally, as you surmised, horn antennas. The particular receiver which detected these perytons, however, has an array of thirteen circular horn antennas (see photo [1] and model [2]). Reflected off the dish, each of these antennas has a separate beam on the sky.
The dish surface is mostly mesh, but the central ~20 metres are solid metal plates, to allow it to operate at shorter wavelengths. I would expect these to have very high attenuation for a transmitter located directly behind the dish.
The pattern of the far side lobes of the telescope is complex, and not well-measured. I have been told that the far side lobes are dominated by scattering off the feed legs (the metal struts that hold the focus cabin in place). Since the feed legs are not visible from behind the dish, this suggests that the side lobes in this direction are relatively weak.
“4) Not all of the perytons were detected at the same point on the sky.”
I think I explained this point poorly. I meant that perytons have been detected with the telescope directed at different points on the sky, and therefore with its back lobe directed at different points on the ground – and so, if they were detected through the back lobe, they could not all have originated from the same point (like a fixed microwave).
[1] https://astronomy.swin.edu.au/cms/imagedb/albums/userpics/HET608-m06a02_0.jpg
[2] http://www.sydneyobservatory.com.au/wp-content/uploads/2012/09/Parkes-multibeam-receiver.jpg
Justin, thanks for the additional detail. I’m sure I could have found all that out by searching material on the Parkes facility but since I only had 5 minutes at the time it was either aim more generally or not comment at all. The temptation to comment was strong since in my youth my first choice of career was astronomy, and preferably radio astronomy, until reality directed me onto a different path.
” I suspect that I may have caused a bit of confusion, though, by using jargon that we don’t have in common.”
The confusion about terminology is my fault, not yours. I knew that might happen which is why I was explicit about what I meant. I tend to distinguish ‘passive’ from ‘active’ elements of an antenna system since I often have had to deal with passive elements that are not always intentional parts of the system. That is, the environment.
“The dish surface is mostly mesh, but the central ~20 metres are solid metal plates, to allow it to operate at shorter wavelengths. I would expect these to have very high attenuation for a transmitter located directly behind the dish.”
Yes, provided the joints are backed by structural ribs that cover the gap. I strongly expect that is the case here. Since I didn’t know the dish material I made my assumption explicit.
“The particular receiver which detected these perytons, however, has an array of thirteen circular horn antennas (see photo [1] and model [2]). Reflected off the dish, each of these antennas has a separate beam on the sky.”
Nice pix — thanks. Since they are close together and pointing in the same direction if noise is reflecting off external surfaces or diffracting into the interior of the dish they would all hear the noise. Are you saying that not all the 13 receive the signal, which would be evidence for an astronomical (or sky) source?
“The pattern of the far side lobes of the telescope is complex, and not well-measured. I have been told that the far side lobes are dominated by scattering off the feed legs (the metal struts that hold the focus cabin in place). Since the feed legs are not visible from behind the dish, this suggests that the side lobes in this direction are relatively weak.”
If there is noise then any metal in its path is a serious problem. If there are no other structures in the vicinity and since (as you said earlier) the structure doesn’t allow the dish to point anywhere near ground level, you are likely correct. In my (unrelated) work I have been aggravated by distant bits of metal that strongly enhance a microwave signal by specular reflection, especially if it’s a flat metal surface.
“I think I explained this point poorly. I meant that perytons have been detected with the telescope directed at different points on the sky, and therefore with its back lobe directed at different points on the ground – and so, if they were detected through the back lobe, they could not all have originated from the same point (like a fixed microwave).”
No, I think your explanation was perfectly clear, as is your tentative conclusion. I was just trying to understand the environmental possibilities for noise incursion, which could allow for detection in seemingly many directions.
Ron, to answer your question, perytons (most or all of them?) have been detected on multiple beams of the receiver. The one used as an example in Burke-Spolaor’s thesis was detected on all 13 beams, with similar intensity (within a factor of 3).
This is strong evidence that they don’t originate from within the primary beam(s) of the telescope, although it doesn’t necessarily mean that they don’t originate from the sky.
Another way for ETI to communicate with us:
http://nautil.us/blog/-if-you-were-a-secret-message-where-in-the-human-genome-would-you-hide
For anyone following this, a paper was posted yesterday on the arXiv [1]. The authors have shown quite conclusively that the perytons do originate from microwave ovens on the site: they can reproduce them by opening a microwave oven while it is still operating. Two separate populations of perytons appear to originate from two specific microwave ovens in different buildings.
Rather than coming in from the back lobe, though, they are detected when there is a line of sight from the microwave oven to the receiver, not blocked by the dish. (See their figure 6.)
[1] http://arxiv.org/abs/1504.02165
More on this next week, when I’ll be discussing this paper.
NO PLACE LIKE HOME: 40 mins ago
Rogue Microwave Ovens Are the Culprits Behind Mysterious Radio Signals
by Nadia Drake
Let’s be clear about one thing: Re-heating coffee in the microwave is always a poor life choice. But it becomes especially unwise if you’re using a microwave oven near a radio telescope and you’re so eager for that icky, burnt and wholly unsatisfying taste that you prematurely pop the coffee out before the oven’s timer goes off.
ZING!
You may have just unleashed a small but mighty radio signal that could be detected by a nearby, sensitive radio telescope. And, if you happen to be reheating your coffee at the Parkes Observatory in Australia, you could be contributing to the growing collection of mysterious radio signals known as perytons. Well, the formerly mysterious radio signals: A study posted to the arXiv on April 9 identified microwave ovens at the Parkes site as being the rather mundane source of perytons.
“It was quite surprising that it ended up being microwaves,” says study author Emily Petroff of Australia’s Swinburne University of Technology.
Full article here:
http://phenomena.nationalgeographic.com/2015/04/10/rogue-microwave-ovens-are-the-culprits-behind-mysterious-radio-signals/
To quote:
Sensitive radio telescopes, like the ones at Parkes, the Arecibo Observatory in Puerto Rico, and the National Radio Astronomy Observatory in Green Bank, West Virginia, can easily detect those rogue microwaves if the telescopes are pointed in the right direction.
“Microwave ovens are a problem for us – and none exist on site. They are prohibited,” says Arecibo director Robert Kerr. Other facilities that don’t ban microwave ovens altogether shield them in enclosures called Faraday cages, which are supposed to prevent detectable radiation from leaking out. In general, scientists try very hard to eliminate any potential source of Earth-based interference from mucking up radio astronomy data – and that means things like cell phones are a no-no near telescopes.
“Alas, radio telescope sites may appear to be occupied by Luddites,” Kerr says. “No microwaves, no cell phones, no wireless routers, no bluetooth printers or headphones, and – more due to funding – often no food.”
So, one of astrophysics’ more exotic mysteries has a surprisingly down-to-Earth solution. But what does this mean about fast radio bursts? Might they also have an Earthly origin?
It seems unlikely, Petroff and her colleagues argue. The intricacies of the fast radio burst signals still suggest an extragalactic origin. And there are clear differences in the time distributions of the two types of signals. As one might expect from a cosmological signal, fast radio bursts tend to show up rather randomly around the clock. But, perhaps unsurprisingly in retrospect, the peryton data show those signals “clustering near the lunchtime hour.”
Aha! A clue, Sherlock.
In my account on Perytons I reported that what was directly behind the dish when it was pointed at the Peryton location was the Visitor Center. I was told that by Emily Petroff and didn’t investigate further. The back lobe of antennas is rarely studied in detail, but is substantially higher than lobes in many other directions-except of course the forward direction. Richard Dickinson tells me that, for the Deep Space Network site DSS –15, measurements of the near field power density pattern give a back lobe width of approximately 10 to 15°. The peak of the back lobe is lower than the average forward aperture power density by a factor of 30. However, these measurements are very variable spatially. There are several microwave ovens on the site and so I would expect that the Peryton would not be in a single location. All this is made pretty clear in the 2001 Burke Spolaor paper.
If it was a microwave oven why are the bursts so short? Is it perhaps a chance chink in the radiation protection of the detector where these signals or reflected ones that they are picked up. Just thinking if metal in the microwave oven is the issue, the number of times I have seen people leave forks and spoons or even the foiling wrapping in their food containers although low does emit an amusing amount of sparks.
Michael, this is explained in this (James’) article and in the new paper linked to by Justin a few comments above yours.
Correct me if I’m wrong, folks, but; according to the Petroff et al ABSTRACT (that’s right, I did NOT read the WHOLE PAPER because I am nowhere NEAR an expert on this subject), even though opened-while-on microwave ovens COULD explain the 1.4GHz component (and many OTHER TYPES pf perytons could explain the 2.3-2.5GHz RANGE, taking into account ALL OF THE RADIO FREQUENCIES of FRB 010724 (i.e. the FIRST one in 2001), the CONCLUSION was that it (and, by INFERENCE. the OTHER 9) could NOT be caused by either of the DISCUSSED (INFERRING the POSSIBILITY ONLY of being caused by UNDISCUSSED perytons (MORE ON THIS LATER). In Paul’s promised upcoming post this week, I hope there is a discussion of SEVERAL other items NOT in the ABSTRACT (i.e. they MAY OR MAY NOT be in the FULL PAPER). These items are: ONE; ALL TEN of the Parkes FRB’s happened in the DAYTIME. Was this due to the possibility of observations by this facility being FULLY OPERATIONAL MOSTLY at daytime hours, or is it ALSO ANOTHER one-in-a-thousand CHANCE EVENT. TWO: Was the Aricibo FRB a DAYTIME or a NIGHTIME event. THREE: What is a “Universal Standard Time” (UST)? Another team has recently reported that ALL ELEVEN (i.e., Aricibo INCLUDED) FRB’s happened VERY CLOSE to these UST’s, implying a VERY STRONG PROBABILITY of earthly interference, the most likely of which being the TOP SECRET SATTILITE, which was not ciscussed in the abstract. AND FINALLY, THE MOST IMPORTANT ITEM: The revelation of the PARKES TEAM that they have FIVE ADDITIONAL UNPUBLISHED FRB’s that do not come ANYWHERE NEAR TO FITTING THE 187.5 PATTERN!
SORRY, I meant UTC times, NOT UST. Can you explain to me what the difference is? Also, this appears to be in an UPDATE from the ORIGINAL TEAM, not another team, as I mentioned above. Will the post on the paper include the UPDATE as well?
Harry, I’ll be working with the copy of the paper just sent to me by the Parkes team.
Also, are you asking what UTC is? It’s Coordinated Universal Time:
http://en.wikipedia.org/wiki/Coordinated_Universal_Time
4/13/2015 @ 7:20 PM 109 views
Bad Week For Alien Hunters
Bruce Dorminey
For alien hunters, the last couple of weeks have been a roller coaster ride. First there were tantalizing hints that so-called ‘Fast Radio Bursts’ (FRBs) scattered across the deep sky tended towards “integerized” mathematical patterns. News of this remote possibility, in turn, created a minor news flap over whether these extragalactic microwave bursts might have some artificial (non-human) origin.
But John Learned, the second author of a paper that raised the specter of communicating aliens from cosmological distances in deep space, has since thrown cold water on the idea.
the FRBs are “surely not cosmic.” In the case of FRBs it is looking less and less likely that we need to invoke extraterrestrial intelligence (E.T.I.),” Learned, a particle physicist at the University of Hawaii in Manoa, told Forbes. He now says, the FRBs are “surely not cosmic.”
In a paper submitted to The Astrophysical Journal Letters, co-author Learned and colleagues analyzed data from 11 known FRBs. After looking at the data, he says the team saw hints that they are a terrestrially-associated phenomenon and not likely to be associated with E.T.
Full article here:
http://www.forbes.com/sites/brucedorminey/2015/04/13/bad-week-for-alien-hunters/
To quote:
Then just last week, came the first results from a survey to look for signs of advanced alien technology in the infrared noise of 100,000 galaxies in data culled from NASA ’s WISE satellite. For now, at least, the G-HAT (Glimpsing Heat from Alien Technologies) infrared survey has turned up a decidedly null result.
If an entire galaxy had been colonized by an advanced spacefaring civilization, the energy produced by that civilization’s technologies would be detectable in mid-infrared wavelengths, Penn State University noted last week.
Jason Wright, an astronomer at Penn State and the lead author of a paper being published by The Astrophysical Journal Supplement Series this week, told Forbes that none of the galaxies surveyed exhibited the telltale signatures of a highly-advanced civilization using a lion’s share of a galaxy’s stellar output for its own energy purposes.
Penn State says the rationale behind the search is that if advanced extraterrestrial civilizations “are using large amounts of energy then at least some of that must be emitted in the mid-infrared.”
Wright and colleagues surveyed some of the closest galaxies to our Local Group of galaxies (a collection that includes the Milky Way and Andromeda, our nearest spiral neighbor). The galaxies we searched, he says, are many tens of millions of light years away, but all lie in our cosmic vicinity.
What’s next for G-HAT?
Wright says he would like to do a more careful analysis that subtracts the expected amount of emission from astrophysical dust — a known, natural source of mid-infrared emission.
Right now, we know that most or all of the emission we’ve detected from these galaxies comes from interstellar “dust,” he says.
“We’d like to know which ones have more [infrared emissions] than would be expected from natural phenomena,” said Wright. “We’d also like to extend our analysis to stars in the Milky Way galaxy to see if any of them show evidence of advanced alien energy supplies.”
Are you surprised that you didn’t find anything?
“I would have been very surprised to find something obvious in our very first foray into this data set,” said Wright. “I expect this is a search that will take a lifetime, or longer.”
April 14, 2015
Search for advanced civilizations beyond Earth finds nothing obvious in 100,000 galaxies
After searching 100,000 galaxies for signs of highly advanced extraterrestrial life, a team of scientists using observations from NASA’s WISE orbiting observatory has found no evidence of advanced civilizations in them.
“The idea behind our research is that, if an entire galaxy had been colonized by an advanced spacefaring civilization, the energy produced by that civilization’s technologies would be detectable in mid-infrared wavelengths—exactly the radiation that the WISE satellite was designed to detect for other astronomical purposes,” said Jason T. Wright, an assistant professor of astronomy and astrophysics at the Center for Exoplanets and Habitable Worlds at Penn State University, who conceived of and initiated the research.
The research team’s first paper about its Glimpsing Heat from Alien Technologies Survey (G-HAT), will be published in the Astrophysical Journal Supplement Series on April 15, 2015. Also among the team’s discoveries are some mysterious new phenomena in our own Milky Way galaxy.
“Whether an advanced spacefaring civilization uses the large amounts of energy from its galaxy’s stars to power computers, space flight, communication, or something we can’t yet imagine, fundamental thermodynamics tells us that this energy must be radiated away as heat in the mid-infrared wavelengths,” Wright said. “This same basic physics causes your computer to radiate heat while it is turned on.”
Theoretical physicist Freeman Dyson proposed in the 1960s that advanced alien civilizations beyond Earth could be detected by the telltale evidence of their mid-infrared emissions. It was not until space-based telescopes like the WISE satellite that it became possible to make sensitive measurements of this radiation emitted by objects in space.
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In any case, Wright said, the team’s non-detection of any obvious alien-filled galaxies is an interesting and new scientific result. “Our results mean that, out of the 100,000 galaxies that WISE could see in sufficient detail, none of them is widely populated by an alien civilization using most of the starlight in its galaxy for its own purposes. That’s interesting because these galaxies are billions of years old, which should have been plenty of time for them to have been filled with alien civilizations, if they exist. Either they don’t exist, or they don’t yet use enough energy for us to recognize them,” Wright said.
“This research is a significant expansion of earlier work in this area,” said Brendan Mullan, director of the Buhl Planetarium at the Carnegie Science Center in Pittsburgh and a member of the G-HAT team. “The only previous study of civilizations in other galaxies looked at only 100 or so galaxies, and wasn’t looking for the heat they emit. This is new ground.”
Matthew Povich, an assistant professor of astronomy at Cal Poly Pomona, and a co-investigator on the project, said “Once we had identified the best candidates for alien-filled galaxies, we had to determine whether they were new discoveries that needed follow-up study, or well-known objects that had a lot of mid-infrared emission for some natural reason.”
Jessica Maldonado, a Cal Poly Pomona undergraduate, searched the astronomical literature for the best of the objects detected as part of the study to see which were well known and which were new to science. “Ms. Maldonado discovered that about a half dozen of the objects are both unstudied and really interesting looking,” Povich said.