The Moon is putting a big wet blanket on this year’s Perseid meteor shower, making it hard to see them.
But that’s OK: if you can’t see them, why not listen to them?
Sounds weird, but thanks to SpaceWeatherRadio, now you can! You’re not really hearing sound, of course: meteors burn up in our atmosphere at a height of 100 km or so, too high to directly carry sound waves. But the Air Force has a radar surveillance facility in Texas that beams radio waves into the sky. When a bit of cosmic fluff streaks through our sky, the ionized trail it leaves reflects the radio waves, producing an echo. This radio wave is then translated into sound, so you can effectively hear a meteor! Here’s an example of a Geminid meteor; it sounds like it could’ve been pulled right off the soundtrack for "Forbidden Planet". There’s also more info on how this works on the NASA science page.
If you want to listen live, here you go. I had it going for a while and heard several faint but distinct dying "Eeeeeeeoooooooo" sounds from meteors within a few minutes (as well as other sharper sounds I’m not sure I can identify, which makes the whole thing even cooler). The best time to listen for Perseids is after midnight Texas (Central) time, but if you leave it running you’re bound to hear a few of those creepy sounds coming from your speakers.
I’ll note that other sounds can be made from radio waves in this fashion. You can listen to Saturn, hear what the Phoenix Mars lander sounded like on its way down to the surface of the Red Planet, and listen to very odd and creepy sounds of the aurorae.
The Universe is talking to us all the time, you know. We just have to have the right ears — and the brains between them — to hear what it’s saying.
Tip o’ the radar dish to BlackProjects on Twitter.
August 11th, 2011 at 9:39 am
The Universe is talking to us all the time, you know.
That would explain those voices in my head…
August 11th, 2011 at 10:02 am
Pew! PewPewPewPewPEW!
Sorry. I couldn’t resist.
August 11th, 2011 at 10:36 am
“The Moon is putting a big wet blanket on this year’s Perseid meteor shower …”
Around these parts a very big wet blanket would have to get out of the way in order to be able even to see the Moon. All the rain that the US isn’t getting this year seems to have gone to Europe.
August 11th, 2011 at 11:15 am
My old gripe: you are writing about a particular instant in time but describe it as, “Midnight Texas (Central) time”. Your dateline gives the time of posting as, “August 11th, 2011 9:34 AM”. Is that UTC? The format suggests it is not and is probably a US time zone. Is this the time where you are? Which county, or even which half of the county, or are you on an Indian Reservation? Perhaps it is the time where the server is located – Ukraine? Is it even the same day in Texas? “Midnight” – is that 00:00:00 or 24:00:00? Would they understand it in Ukraine? How do you convey time to your fellow astronomers?
100% cloud cover here, so no Perseids unless one comes through the skylight.
I am posting this at about 17:15:00 UTC, so lets see what time comes up.
August 11th, 2011 at 11:21 am
This sounds somewhat similar to the meteor radar we operate out of Southern Ontario for the University of Western Ontario: http://meteor.uwo.ca/research/radar/cmor_intro.html
Along the same lines, we’re also dabbling into observations of VLF emissions from bright fireballs.
August 11th, 2011 at 11:43 am
I had posted this on another thread but thought it more relevant here: Back in 99 when I stayed up all night to watch the Leonids, during the peak there were multiple meteors per second. The really odd thing was the noise that they made – lots of hissing and popping. I understand that at that altitude the sound would take quite a while to reach the ground, (if it could be heard at all) but it was instantaneous. I read in Astronomy magazine that the sound might actually be radio frequency emissions, that we somehow percieve as sound (not sure how that works – maybe it’s the tin foil hat I wear to silence the voices). Either way, we all confirmed what we heard (there were 5 of us) – it was loud and unmistakeable. Truly a breathtaking event that I will remember as one of the most amazing sights/sounds I will probably ever witness.
August 11th, 2011 at 11:59 am
That sounds like it could possibly be VLF? VLF overlaps the range of human hearing quite well (VLF is 3kHz-30kHz, whereas human hearing is, give or take, 20Hz-20kHz). In fact, our VLF experiment is able to use common, off-the-shelf studio grade audio equipment to digitise signals, because they are sensitive to the same frequency ranges.
Of course, VLF is electromagnetic, so you wouldn’t hear it directly. It would have to induce vibration in some ground based object, which would convert it to audible sound. I believe this has been shown to be possible, but I’m unsure what sort of power is required. It would explain how the sound was transmitted “instantaneously”, though.
As an aside, there is also a project to listen for the infrasound shockwave of a meteor travelling through the atmosphere as well: http://meteor.uwo.ca/research/infrasound/is_meteorIS.html
August 11th, 2011 at 12:33 pm
I’ve experienced the hissing sound as well, and I knew at the time that it *shouldn’t* be happening, but, dang, definite hisses perfectly coordinated with the visual meteor. I have a couple possible experiments in my head involving this that could be done cheaply, but they will have to wait until I am retired. It’s an interesting phenomena because it’s still up for debate what’s happening.
August 11th, 2011 at 1:28 pm
Interesting, I’ve also experienced that sound almost like an old fireworks fuse hissing and popping as it burns.
I’ve only ever really seen it with particularly bright meteors though.
August 11th, 2011 at 1:34 pm
I’d like to mention the irony in that the Air Force won’t allow me to listen to Air Force radio surveillance on an Air Force computer. Can’t complain too much, I’ll be watching the shower in Sicily.
August 11th, 2011 at 1:38 pm
Ham radio operators have long used meter showers to communicate long distance by bouncing radio waves off the ionized trail left by meteors. mostly in the 6 to 1 meter range (50 Mhz to 220 Mhz)-we hear them all the time.
And you can get VLF radios surplus from the navy-they use them all the time in submarines.
August 11th, 2011 at 2:30 pm
@Alan – in this case its not relevant what in what time zone Phil posted this. He’s telling you after midnight Central Time. That’s all you need to know – you don’t need the date, you can listen anytime this weekend.
August 11th, 2011 at 2:59 pm
Thanks for the link, JRG. Do you broadcast the sound too? I couldn’t find a link similar to space radio (thanks for that, Phil…I’ll be tuning in if Ontario doesn’t have something similar).
August 11th, 2011 at 5:21 pm
Actually, “Whether you can hear it or not, the universe is laughing behind your back.”
August 12th, 2011 at 1:08 am
We were loading our gear into the van after a gig in Cheshire sometime in the ’60s and saw a beauty. It split into three, a large central piece and two smaller ones that diverged on either side. Several seconds later we heard a sound that is best described as what you would hear if you held a flag out of your car window when travelling at speed. The sound didn’t last more than a couple of seconds. There was no hissing or crackling.
August 12th, 2011 at 4:30 am
You can also listen in on shortwave radio; you don’t need an expensive RADAR installation to ‘hear’ the meteors. The only reference I could find in 5 minutes suggests using FM radio though:
http://www.thrushobservatory.org/radio.htm
August 12th, 2011 at 4:54 am
@KC – As I said, it is an old gripe. Why should scientists use such an arbitrary system of units for describing the time? To keep in step with civil time, we have to live with leap seconds and leap years (that is a pair of very inconsistent terms). But Time Zones! We have had 9 European Directives to settle on the start and finish of DST. But whether a country observes DST, and what time zone they are in, is still subject to political whim. In the US, DST is not only celebrated on different dates (which are themselves variable) to the EU but the changeover occurs at different instants in different zones (if it occurs at all). Other countries are even more bizarre.
‘Now’ is ‘now’ everywhere (give or take a bit, or a lot, as the case may be).
No doubt, in the US, people are used to adding or subtracting an hour or three to get the time in another place. From Europe, it means counting on your fingers; from other places, it is fingers and toes, or fractions thereof.
The same might be said of other units, but that rant can be saved for another day.
No Perseids last night, because of the moon, no Perseids this morning, because of the sun; but actually there is very little difference here – so, SpaceWeatherRadio it is.
August 12th, 2011 at 5:04 am
[...] what a meteor shower sounds like? Me either – but it’s kind of scary. Check out this article on Discover Magazine’s site from Phil Plait about listening to the radio waves generated by meteors as they streak across the sky. I [...]
August 12th, 2011 at 5:18 am
With all the cloud cover in the UK we are holding our breaths for something decent tonight. We were hoping to film something for the 23 degrees series (www.bbc.co.uk/23degrees) but the full moon looks set to ruin the show. Was hoping there was some kind of camera that could be of extra use in this type of situation but no joy.
Sounds of a meteor shower sounds cool, something out of a science fiction movie http://365daysofastronomy.org/2011/02/02/february-2nd-meteor-detection-by-radar-for-the-amateur-observer/
if you can’t see you might as well listen to it
August 12th, 2011 at 10:28 am
I’ve never heard of anyone hearing meteor noises as #6 and #8 suggested, but I’ve heard of people hearing hisses and crackles during auroras. Does anyone know about these, and if they have been investigated?
August 12th, 2011 at 1:24 pm
[...] Via Bad Astronomy [...]
August 12th, 2011 at 9:26 pm
@Daniel – sorry, the UWO radar is primarily a research tool, so we don’t have anything neat like audio streaming set up.
August 12th, 2011 at 9:55 pm
Overcast in the heartland tonight, so the boys and I sat down and listened to them on the ‘net. Very cool, and they got pretty good at telling the difference between a meteor, satellite, and airplane. Thanks for this link, BA.
August 13th, 2011 at 7:57 pm
How to Bounce Amateur Radio Signals Off Meteors
http://www.ehow.com/how_6523147_bounce-radio-signals-off-meteors.html?fb_comment_id=fbc_5005767847443_653093_5006669051443