The Sound of Meteors - Sixty Symbols

Professor Mike Merrifield discusses meteor showers - and whether it's possible to hear meteors travel through the sky? More links and info below ↓ ↓ ↓

This project features scientists from The University of Nottingham

Sixty Symbols videos by Brady Haran
Additional editing by James Hennessy

[abigailcooling]

Mike Merrifield and Sixty Symbols is the best thing to come home to after a difficult drive to uni and back.

[Nethershaw]

When I was a kid, I had a handheld AM radio; during thunderstorms I figured out I could tune it to the high end of the dial, between 1400-1600 KHz, and listen to the ionization signals of lightning strikes from all directions.

[caffiend]

I'm one of those who has heard the hiss of a meteor overhead. I was on a back road in AZ out in the desert in the middle of the night in the late 90s. We parked and turned the car completely off and sat for 20+ minutes to allow our eyes to adjust. Given the location it was also dead silent. Eventually, an exceptionally bright meteor streaked directly overhead, leaving a greenish ionized trail for a couple seconds. I've always been a nerd so I wasnt expecting be able to hear anything, but i did. It was a really strange noise and it definitely seemed to come from all around as opposed to directly from the meteor itself. Definitely some kind of electromagnetic phenomena given the sound seemed to travel instantly. I would not be surprised if the climate/terrain/geology of the area was a factor. It was cold, dry, and dusty.

[bsadewitz]

When I was a teenager, I went on a camping tour out west, and we observed a meteor shower in Southern California. It's true: simply lay back let the sky fill your view. It was absolutely gorgeous. Reflecting on the experience, I see now why old testament cosmology characterizes the sky as a dome hammered into shape, or a sort of tapestry thrown up into place and spread out. Indeed, after one gets acclimated to viewing the entire sky, it takes on a depth that it doesn't ordinarily have. Definitely a "flashbulb" memory for me.

I would be interested in learning more about the signals from a meteor shower propagate.

[XPL]

Yes! I have also heard the hiss of some of the brighter meteors I have seen but assumed I was making it up since I also heard the sound almost instantly. Glad to have at least a possible explanation for it.

[bariumselenided]

Given how often I feel my phone buzz in my pocket only to find there's no notification, and how often I can hear game sound effects even when playing on mute, I imagine the meteor sound is just a hallucination of similar sort. Certainly a ball of fire streaking across the sky looks like it ought to be hissing, so it makes sense that brains would hallucinate in the hiss.

[docostler]

The description of the sound of meteors reminds me strongly of the sound of the aurora, which I have experienced many times while working in the subarctic of Canada. (I've seen the northern aurora in many places further south, but the subarctic was quiet enough to make awareness of it much more likely). I've always accepted that it had been 'proven' to be a false sensation, although I could not tell you if there is any current explanation.
I still maintain that the sensation is real even if the meteor itself has not acoustically impacted my ears.

[Pants]

I am pretty sure I heard a particularly bright long-trail meteor, once, when it was windless and totally silent in the middle of winter. I was convinced that the faint "hissing" sound came from behind me, where there were trees. I was with three other people, and all three said they heard something too. Could still be coincidence, but that VLF radio-wave theory is intriguing. My favorite way to listen to meteors, though, is via meteor-scatter radio reflection on an HF or VHF radio, where a strong transmitter over the horizon can have its signal bounce off the fleeting ionized trail. They sound particularly eerie, and there's often a strong doppler-shift component, i believe as the ionized gas molecules slow down after they're initially accelerated. You can find some examples (and even livestreams) on youtube, often labeled "meteor radar".

[yzftony]

Ham radio operators call this "meteor skip", it's part of the "amateur extra" exam In the US.
Also, you can use a radio tuned into an AM blank space to hear lightning bolts, it sounds like a welding arc when they discharge.

I'll see if AM works for detecting meteors sometime.

[williamk]

I remeber seeing a significant meteor shower when I was a very young child some 25 years ago. I vividly remember a rather large meteor streak across the sky and hearing a hiss as it was crossing the sky. I must have been 4 or 5 years old at the time.

[kirkhamandy]

I've done the HAM radio thing of "meteor bounce", and it's fun. Regarding actually hearing the sound of a meteor, I dismissed this for years until two people I trusted told me they heard one together. I've been trying to match any VLF reception with a "beacon bounce" to see if any meteor emits a VLF radio signal. So far, no luck, but I'll keep trying

[toerroris]

I've heard the ffft sound; I was lying on the floor and had glasses on at the time. Also, I'd never heard of the sound before - had to look it up after the fact.

[metdupm]

I’ve heard the sound from an incoming meteor a few times and it’s generally a pretty soft sound, but I’ve had two experiences when it was actually loud enough to be heard over background noise. On one of those occasions it was enough to interrupt a conversation I was having at the time.

[parsias]

Pretty cool! I had no idea of the relationship between comets and meteor showers.

[toughenupfluffy]

I was once camped in the Rocky Mountains of Colorado at about 11, 000 feet above sea level, in the late 1970s. Me and a few friends were laying outside of our tents, watching the night sky for the Perseid meteor shower. Suddenly a big bolide—a meteor that breaks apart and creates multiple streams of ionized gases—shot across the sky above our heads. It seemed to be pretty low in the atmosphere, compared to the distant horizon, where we could still see the remnants of the sunset. It broke into five or six big pieces, shooting across the sky and raining down glowing embers.
We heard it _loud and clear_, and the sound was instantaneous with the breaking apart of the bolide. I knew it was at least a few miles above us, so I was astounded to hear it like that, without any time delay between the phenomenon and the sound. It's something I'll never forget, absolutely incredible.
Professor Merrifield's explanation of the low-frequency radio waves is the first time I've ever heard anything that might explain the phenomenon.

[monstermoonshine]

There were also reports that people "heard" aurora, maybe this is worthy of an episode?

[goose]

I've heard a meteor shower before. And I'm sure I wasn't imagining it. This was about 22 years ago. I was lying down in a field watching a meteor shower in early spring in Argyll, Scotland. The dew had fallen, and the grass around me was just starting to freeze up. The whole area was absolutely silent, no people around, no wind, in basically the middle of nowhere.

With some of the bigger shooting stars, I could hear a very faint sort of hissing/rustling while they got bright, and sometimes a sort of pinging sound when the meteors burned up or exploded. It was as if the grass around me was somehow reacting to it. My silly teenage brain at the time thought that I was hearing pressure waves from the meteors bouncing off the grass!

Then a few years after that, I came to the conclusion it must be coincidence/imagination. That I was fooling myself by expecting a hiss because I was associating it with fireworks or something. But years later I heard of this VLF phenomenon, and I'm certain that's what I was hearing back then. If anyone wants to read more about it, it's a subject known as 'electrophonic meteor sounds'.

It can only probably be heard in very quiet areas with certain conditions - not sure. Seems very rare and hard to detect anyway.

[CamMci]

I camped out and had my head sticking out the tent for hours. I saw many shooting stars but I only heard one of them and it was by far the brightest and most incredible shooting star I’d seen. If it were an illusion wouldn’t I have heard it for all of them?

[dexyfexx]

I was in a car once and saw a very bright meteor during the day. It was very fast moving and a greenish colour, and I could swear at the time I heard a weird high pitched "falling bomb" or descending jet engine type noise at the same time, fairly quiet but only for that brief fraction of a second. It was weird because the sound seemed like it was coming from inside my head, or from everywhere around me. But the other person in the car didn't hear anything, even though we both saw it and were amazed what we witnessed. It was a very high pitch sound though, and apparently I can often hear very high pitched things that other people can't, eg old CRT screens. As a physicist myself I had no explanation for what I experienced other than maybe it was some kind of RF thing, due to there being no delay in hearing the sound. So it's very interesting to hear that possibly others have experienced something similar!

[viliamklein]

I don't know about audible frequencies, but bolides do make infrasound when they burn up in the atmosphere. About 10 years ago I worked on a project demonstrating that we can hear these infrasound waves from NASA high altitude balloons. But it's hard plan on having a sufficiently large bolide fly near the balloon during a short 24 hour demonstration flight. So we paid the company that blew things up for the Myth Busters, EMRTC, to set off a large explosion for us in New Mexico and then demonstrated that we could hear it from more than 100km away and in the stratosphere. Good times.