Image credit: Pierre Auger Observatory Team,
What is the so-called “OMG Particle”? Where could it possibly come from, and how are magnetic fields involved? How can we detect these cosmic rays? I discuss these questions and more in today’s Ask a Spaceman!
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EPISODE TRANSCRIPTION (AUTO-GENERATED)
So first off, thank you to everyone for sticking through that multi part epic saga of general relativity. It was like, for me for me, I know it's not the longest podcast in the world, but for me that was like the Iliad of podcast. It was just this giant poem of of of this crazy battle of grappling with gravity and Einstein's struggle. It was it was great. And I could have gone on longer.
There were, like, entire sections of my notes that I got to. And I said, as I was reading it, as I was I would get to section of my notes and say, I'll just skip it. I'll just skip it because I know this is running long. So I'd love your feedback because that was an experiment for me on longer multi part episodes. I know we've done two parters before.
That was the first time I've done a three parter. It could have easily been a four parter. I have way more material, so I'll just have to save that for a new episode. It was an awesome journey for me. I hope it was an awesome journey for you too.
Would love your feedback. If you'd like to see more of those multi part episodes or you like the single ones like today's, just let me know. I'd love to hear what you thought of an episode series like that. But on to today's topic, because after a heavy meal, like, I don't know, all of general relativity, I need I still I'm still a little bit hungry even though I have a giant, greasy, gut busting meal. You know, you have just, you want something sweet.
You want just a little bit of dessert to just top it off and to call it a night. And that dessert for us today, after the three part general relativity series, is a mystery. A high energy whodunit. And the mystery begins on the night of 10/15/1991. It was a cool, dry, dark in the desert, Western Utah Desert, and there the University of Utah's fly's eye cosmic ray detector saw a brief scintillating flash of light.
The source of that light most likely a proton traveling into the atmosphere at an incredible velocity And since then, the mystery has only gotten deeper. I am talking about what is now known as the o m g particle for oh my goodness. Oh, whatever it's it's a particle. It's a high energy particle in it what came screaming is the atmosphere. The energy of this thing.
I'm gonna throw some numbers at you to give you a sense of the energy of this little proton that struck our atmosphere with an energy of 3.2 plus or minus point nine times 10 to the 20 electron volts. Now an electron volt, I've talked about briefly briefly before. It's one of these gloriously arcane and nonsensical units in jargon physics that make zero sense outside of the physics world. So very briefly, an electron volt is the amount of energy it takes to move one electron across one meter of one voltage potential difference. That ends up being sort of useful in things like particle accelerators, and so that's why you see the e v or electron volt tossed around in that language, in that, framework a lot.
This and and so okay. That's a large number, 10 to the 20 electron volts. Volts. Wow. That sounds impressive.
What does that even mean? The Large Hadron Collider, the world's most powerful particle accelerator, our atom smasher extraordinaire is capable of 13 teraelectron volts, which means this little particle, this proton, hit our atmosphere with an energy 10,000,000 times greater than our most powerful particle accelerator, 10,000,000 times over. It's the same energy, to give you some sense of of these electron volts, this 10 to the 20 electron volts, that's the same amount of energy in a a middling fastball. You know, a baseball that's thrown but not, like, full on about half the speed of a of a really fast fastball. So, like, I don't know.
It's not a slow ball, medium ball. I I don't know if there's a baseball jargon term for it. And that doesn't sound like a lot for a baseball. Yeah. You know, if a baseball hit you going 50 miles per hour, it would hurt.
It would hurt. It'd be a bad day, but it wouldn't ruin your life. But take all that energy. Take imagine this massive baseball and squeeze it down, squeeze it down, squeeze it down so it's smaller and smaller and smaller, and then the smaller you make it to keep the same amount of energy, it has to go faster and faster and faster. Squeeze it down to the size of a proton.
So you're taking all that energy in the entire baseball, and you're squeezing it down to below microscopic proportions to the size of a proton, and you can see why this thing is packing a serious punch. Its speed is ridiculous. It's going a good fraction of the speed of light. Are you ready for this? Are you I'm not gonna make up a symbol a single one of these nines that I'm about to read off to you.
The percentage that this particle is traveling compared to the speed of light was 100 the speed of light. That is really, really, really close to the speed of light. If there was a race between a beam of light and this proton, then, of course, the beam of light would win because nothing can beat a beam of light. But it would be a it would be a a a neck and neck finish if these things were racing across a one light year race track. So the gun goes off, and then the beam of light and this proton go off.
They're racing each other. The beam of light would win by 50 nanometers. 50 nanometers, which is like nothing. This proton is this single subatomic particle. A single proton has so much energy associated with it that 10 to the 20 electron volts and remember, mass is energy, energy is mass.
It's the mass equivalent of a bacterium. A creature has the equivalent amount of mass as this single particle because of its speed. Here's some more ridiculous numbers. Like, this is but this is why we call it the OMG particle because you're like, wow. OMG.
That is an impressive particle. You know that the faster you move through space, the slower you move through time. If you don't know that, go back and check out the equals mc squared episode two parter because I dig into that. The faster you move in space, the slower you move in time. Moving clocks run slow.
So in the frame of reference of this proton screaming at nine nine point nine nine nine nine, etcetera, percent the speed of light, it could travel the distance from the sun to Alpha Centauri. That's 4.36 light years. It could do that in less than half a millisecond. Half a millisecond, it can make the jump in its own local frame. It could reach the galactic nucleus 32,000 light years away in three seconds.
It could hop to our nearest neighbor galaxy, the Andromeda, in a few minutes. It could reach the Virgo cluster in a little over an hour. It could reach the edge of the known universe, the edge of the observable universe, that distance in nineteen days, a couple weeks, and you could take a road trip on this particle to the edge of the observable universe. And just like moving clocks run slow, when you're traveling, when you're moving really fast, lengths tend to shorten along the direction of travel. This is called length contraction.
It's the two sides of the coin of relativity, of moving clocks run slow and lengths appear to shorten. So in the frame, if you're riding along with this particle, things would appear incredibly flattened, like the entire Earth would appear to be a third of a millimeter across. A pancake a third of a millimeter across. Our solar system would be about 37 meters. The distance between the sun and Alpha Centauri would be about, a hundred kilometers or so.
The entire Milky Way is, like, 3,000,000 kilometers, which that's a large number, but you're taking an entire galaxy and squeezing it down. What the mystery is, what the who done it is, is this OMG particle, Who the heck in the universe is capable of making a particle go this fast? Who? It's not me. Pretty sure it's not you.
It's not the sun. Who who does this? Who does these kinds of things? So let's dig in. So so this is a cosmic ray, and the OMG particle is one example of a broader class of particles that are constantly coming screaming into our atmosphere.
They're called cosmic rays. They're not rays. I even put in my notes. Do a dramatic sigh here. It's they're not rays.
Okay? It's just a historical accident. Just just forget about it. Cosmic rays are really tiny little particles. There's the beep things.
They're electrons. They're protons. Sometimes they're helium nuclei all the way up to iron nuclei. They're just buzzing around the universe. There's around a bajillion of them, give or take another bajillion.
There's a bunch manufactured by the sun, AKA the solar wind, and a bunch come from outside the solar system from a bunch of sources that we're about to go into. We're used to the idea of light flooding the universe, like, okay, like photons are everywhere, they're spit out by all the stars and the hot clouds of gas and all that kind of stuff in the cosmic microwave background and all that, so the universe is flooded with light. The universe is also flooded with fast moving particles. These tiny little things buzz around like rain, like drizzle, constantly bombarding everything else. It's hard to see them though.
Right. It's not like you see these little tracks and flashes right before your eyes in your daily commute. You see the light because you have eyeballs, but you don't have cosmic ray detectors built into your skull, so it's a little bit harder to see the cosmic rays. But you can, and and the crazy thing is, you can actually detect cosmic rays or the byproducts of cosmic rays with a few simple homemade ingredients. There's a few different setups to make what's called a cloud chamber, which is a chamber containing a cloud which lets you see cosmic rays.
And one of my favorite constructions is to take an aquarium, you know, like a 10 gallon pretty standard aquarium, and get some dry ice. If you're wondering where to get dry ice, frozen, carbon dioxide, just go to an ice cream shop and ask, like, hey. Can I have some dry ice? And they'll sell it to you or they'll just give it to you. They got a lot, so you can just buy from them.
And you put the dry ice underneath the fish tank, and then you put a piece of metal between the dry ice and the bottom of the fish tank or just on top of the bottom of the fish tank. The point here is to try to make that layer, the bottom layer of the fish tank, as cold as possible, and metals are good at doing that. And then you pour some rubbing alcohol into the tank, and it will make a cloud because it's really cold. The densities are really low. The temperatures are really low, and you you get a cloud in the bottom layer of the fish tank.
Then you turn off the lights, and you shine a flashlight into your little cloud, and you just watch. You just watch, and you'll see the the cloud rolling, roiling back and forth, and it's pretty interesting. But every once in a while, you'll see a little bing, a little zoop, a little track appear like a tiny little bullet cross the path of that cloud. And what you're seeing is a cosmic ray pass through the cloud or a particle produced by cosmic ray when the cosmic rays hit something higher up in the atmosphere. And as the cosmic ray or its secondary particle, which is what we call the byproducts, the secondary particle comes through that cloud.
It ionizes bits of water vapor, which serve as further nucleation points so you get a brief moment, a streak of higher density of, like, little tiny water droplets condensing and then eventually evaporates away. These cosmic rays, which are impacting you all the time, most of them, like, just about most of everything are kinda wimpy. I mean, they're still traveling at half the speed of light or something, but they they don't really carry a punch. They're interesting to look at and they're cute, but they don't really pack a wallop. And some of these cosmic rays are slightly more energetic, and a few are intense, like the OMG particle.
We think the OMG class particles, which we call ultra high energy cosmic rays, so not just cosmic rays, not just energetic cosmic rays, not just high energy cosmic rays, but ultra high energy cosmic rays, the rarest of the rare, will strike the Earth about once per square kilometer. So if you stake out a grid kilometer by kilometer, it will hit that area about once a year. Compare that to your cloud chamber experiment where you're getting a few cosmic rays, like, every second. One particle per square kilometer per year. That's the rate of these ultra high energy cosmic rays.
We have since the OMG particle was discovered in 1991, it's been a while, but even in that little while that while, like three decades, nearly three decades, we have around a hundred of these ultra high energy ones. That's it. So that's part of the mystery of the OMG particle and all of its friends that we've collected since then, is there not a lot of them, and when you don't have a lot of things, it's hard to do statistics, it's hard to do science. Of course, cloud chambers was how I first identified cosmic rays way back in the good old days, in the black and white days. Now, it's full color.
We have more sophisticated instruments. Usually, when a cosmic ray comes into the Earth, encounters the Earth, it hits an air molecule, it'll hear some it hits some oxygen or nitrogen, and it this creates this interaction destroys the original particle, transforms its energy, creates a shower, a cascade of lower energy particles, some temporary pions, some muons, some neutrinos, some other guys that create this cascade that eventually reach down to the ground. So you can directly detect those secondary particles. If you have a detector on the ground, like, say, a giant vat of water, you can see when these secondaries enter the tank of water. You have detectors ringing the water.
You can look for some telltale signatures, and you can spot the secondaries. You can also see when this event happens up in the atmosphere. It can produce a special kind of light called Cherenkov radiation. That's a fun one to to roll around in your mouth. Cherenkov radiation.
When a particle zips through a medium, like air, faster than the speed of light in that medium don't get sassy with me. It's not the speed of light. Nothing beats the speed of light, but some things can beat the speed of light in a medium, like travel slower through water or air, and you can beat that. When you do, you give off a particular kind of radiation, very bluish, ghostly, kinda cool looking radiation called Cherenkov radiation. So you can just look for that.
You just make a special telescope and just check and look for Cherenkov radiation. You can also look for fluorescence, where as the cosmic ray passes through the atmosphere, it ionizes air molecules, which they eventually reattach and then give off a little bit of light the exact same way the aurora work. So you can look for that fluorescence, and that is exactly how the OMG particle is discovered. Or you can directly detect it, like I mentioned, in, say, a giant vat of water from its secondaries. No matter what, you have to reconstruct the original cosmic ray detection direction and energy because you're not actually capturing the original particle, you're looking at some byproduct like a flash of light or the fluorescence or its shower of secondary particles.
So you have to do some detective work to pinpoint, okay. We're pretty sure this particle that created this shower had this much energy, was coming in roughly this direction, etcetera, was made of this, etcetera, etcetera. So there's some detective work in figuring out how cosmic rays work. So let's go back to the original question. How do cosmic rays, like, become themselves?
How do they get so fast, especially the ultra high energy ones? How do you shoot a particle to get that close to the speed of light? Well, would you believe that it's magnetic fields? That's right. It's been a while since I've had to invoke magnetic fields, but here we are.
Here's how magnetic fields play a role. There's a lot of energetic events in the universe, and we'll get to them. Stuff blowing up, stuff mixing up, stuff colliding. And you can have in the vicinity of that energetic event a bunch of charged particles just loitering around, you know, causing mischief, but not no real harm. You know, they're doing graffiti or something.
And then, bam, they get hit by the violent event. They get caught up in, say, a giant jet. They get caught up in the shock wave of an explosion. And since they're charged particles, they respond to magnetic fields. Magnetic fields can take and grab hold of charged particles and whip them around to do something interesting with them.
The magnetic fields play a role here in these events because they're like the middlemen. They take the energy from the event, say the raw kinetic energy, and they transform it into a kinetic energy of the particle itself. They accelerate the cosmic rays. They whip them around. They can bounce them back and forth.
There's all sorts of cool mechanisms for using strong magnetic fields to accelerate a population of charged particles and turn them into cosmic rays. I'm being hazy on the details here because the details are kinda hazy. It's a ferociously difficult problem to solve in each one of these scenarios. The physics is hard, to say the least, and there's a lot of open questions on the details. Not the broad brush.
We know that there needs to be a source of energy. We know that magnetic fields have to be involved because they do the work of accelerating these charged particles. And then, like, the details are a little bit hard to come by because the physics are hard. So we know the gist of how cosmic rays are generated. But in the case of the OMG particle, how do we make a cosmic murderer?
Like, how do you make something this fast, this energetic? Well, whoever did this, whoever made the OMG particle, we know at least two things. We know it had to be powerful, had to have enough raw energy, and it had to have strong magnetic fields so that it could actually accelerate this particle. So let's line up the usual suspects in the universe who might be capable of making something like an OMG particle. Suspect number one, supernovas.
The deaths of massive stars. Definitely powerful. For sure, Sherlock. The shock waves in one of these explosions carry a strong magnetic field. They can act as a mirror that bounce wiggle the particles back and forth a bunch of times, giving them more and more frenzies, and then finally the particles escape as cosmic rays, but they're not powerful enough.
Supernovas, think about this, the death of a massive star, one of the brightest things we can see in the universe, are not powerful enough to make an OMG particle, and supernovas are too common. Supernovas happen, like, basically all the time, and we don't see OMG particles all the time, only one per year per square kilometer. Supernovas are too weak, and they're too common. They get off the hook. What about gamma ray bursts?
GRBs. Yes. These gamma ray bursts, which deserve their own episode if you'd like to hear more about gamma ray bursts, please ask. They're thought to be the deaths of the most massive stars, like catching the birth of a black hole just as you get a transition from a neutron star to a black hole. There's a very powerful accretion disk around there that's angled and and jet it's it's okay.
It's interesting. It's interesting. Again, there are giant shock waves. Again, there are magnetic fields. There are special alignment, so there's powerful jets, all the good stuff.
In reading the literature on gamma ray bursts, the term cannonballs is used freely, and and that's very intriguing to me. Likely oh, for sure, gamma ray bursts generate cosmic rays. Just like supernova generate cosmic rays, there's no question about that, but we're asking about the big bad ones, the OMG type particles. It seems, and this is a little bit sketchy, I know, that gamma ray bursts, as best we can tell from simulations and analysis, don't have the right mix of energies and timings to make an OMG class cosmic ray. They're still kind of a contender, but not a favored contender because it just doesn't add up right.
The energy that is released during a gamma ray burst doesn't happen at the right kind of timescales in the right places to coincide with driving a strong magnetic field to actually accelerate a population of charged particles and actually make an OMG. It might make an oh, wow or a that's interesting particle, but not an OMG particle. Sorry. And, again, I'm being vague because the physics is let's just say it's messy. Alright.
So gamma ray bursts probably off the hook. What else is energetic in our universe? I know. Active galactic nuclei. These giant supermassive black holes in the centers of galaxies that are actively feeding massive accretion discs, tons of radiation, powerful jets.
Wow. That's a lot of energy. They are by far the most powerful engines in the universe. EASILY powerful enough, multiple times, they can generate an OMG particle without breaking a sweat. But there's a problem.
Most of the active galactic nuclei or AGN are far away. You know, they're they're come from a different time in our universe, when our universe was a little bit younger, a little bit more frenetic, a little bit more wild and crazy, when galaxies were merging all the time. We see AGN active galactic nuclei in the distant universe, which means they existed when the universe was much younger. Well, why is that a problem? Well, remember these ultra high energy, OMG particles, cosmic rays, are traveling super close to the speed of light, like, almost there to the speed of light.
To these particles that are screaming through the universe, You know that cosmic microwave background, that flood of low energy, red shifted light left over from the early days of the universe? It's cool. It's almost at zero. It's like three Kelvin right now, firmly in the microwave. It's just this weak background bath of radiation.
Well, when you're traveling fast through the universe, that radiation becomes blueshifted. It appears more energetic. It's not just some annoying background static. It's blueshifted to high energies, which can throw some serious interference to a fast moving particle. From the perspective of these cosmic rays, the ultra high energy ones, the cosmic microwave background isn't just like a gentle spring drizzle.
It's a full on hurricane, and those high energy photons from the now blue shifted cosmic microwave background are gonna throw some static. They're gonna get in the way. They're gonna run some interference. They're gonna block. They're gonna deflect.
They're gonna pull energy out of the cosmic ray. It's gonna slow it down. So we can put a limit on how far away the most energetic cosmic rays can come from, and it's somewhere around a 50 or so million light years. We're pretty sure that if you see an ultra ultra high energy cosmic ray like the OMG particle, it could not have come from farther than a 60,000,000 light years away because it'd be just too much hurricane to go any further than that. The cosmic microwave background is too intense for it.
It would have sapped its its energy, and it wouldn't have made it to Earth. There's also an energy limit associated with this. Like, even if you put nearby sources, even if these ultra super duper whatever wackadoodle cosmic rays are coming from nearby, there's also an energy limit where we shouldn't see particles, cosmic rays above a certain energy. And it's somewhere around that threshold of the o m g particle itself. Some experiments, by the way, see this cutoff.
Some don't. It's debatable. It's hard to measure the energies of these suckers anyway, so I won't get into that too much. What this tells us is that whoever made the o m g particle has to be powerful, ridiculously powerful, has to have strong magnetic fields, and it has to be close. It has to be right in our galactic neighborhood.
It's it's it's the people you don't suspect. It's the nice looking family neighbors. It turns out those are the ones. So who could it be? Could it be you?
Could it be Patreon? Could it be you who's supporting this show, patreon.com/pm? Sorry. Yes. It is you who make this show happen, who give me the funds I need to keep doing education and outreach, talking about all this juicy science stuff.
Go to patreon.com/pmcenter. I'd greatly appreciate it. Also, check out astrotourist.co. We have a brand new trip to Costa Rica. Me, Fraser Cain, Costa Rica, tropical jungles, awesome skies.
Go astrotourist.co. Another suspect. We need someone powerful, strong magnetic fields, and close. What about Centaurus a? Centaurus a is an active galactic nucleus.
It's the closest active galactic nucleus to us. It's only 10 to 16,000,000 light years away, which is close enough. It's within the limit and it's a single object. It's the most powerful thing in the nearby volume of the universe. So it should be pretty cut and dried.
Like, you just ask, okay. Where are all these cosmic rays coming from? Do they happen to all come from the direction of Centaurus a? Well, then bingo. We've got a match.
It's a little bit more difficult than that. Some observations have hinted that the OMG class particles come from the direction of Centaurus a. It's hard to tell because our own galaxy has a magnetic field, which is kind of annoying. I mean, it's cool, but it's also annoying for these purposes. And as the cosmic rays come screaming in from intergalactic space into our own galaxy, our own galactic magnetic field can subtly, very slightly shift and tilt the trajectory of those cosmic rays.
Remember, they're charged particles. They respond to magnetic fields. They talk to them. They'll listen to them. And even though our galactic magnetic field isn't really strong, it can still subtly you can whisper to us, hey.
Why don't you go over here and say just a little a little to the left? Just a little yep. Yep. Yep. No.
No. Nope. Too far. No. A little bit to the no.
Perfect. Perfect. It can just subtly tilt the trajectory of these particles as they rain into our own galaxy. So to reconstruct so we see a cosmic ray coming into our own sky, but if we know that the cosmic ray came from outside of our own galaxy, then we have to do some adjustments. We have to model our own magnetic field and its influence on the cosmic ray.
We guess what? We don't have a full picture of our own magnetic field. So the modeling has some uncertainty. So we're not I'm basically saying we're not exactly sure where these high energy cosmic rays are coming from. It's a little bit hard.
Also, it's hard because there's, like, only a hundred of them tops, so it's hard to do good statistics. It seems unlikely. It's it's quite possible that Centaurus a is responsible for at least some of the cosmic rays, the high energy cosmic rays, but probably not all of them. So what else is there? Well, there's C FERTS.
C FERTS, if you remember from the quasar episode, it's a kind of active galactic nuclei. They tend to be closer. They they're weaker. They're of the weaker variety of AGN, but, you know, they're still pretty dang powerful, more than powerful enough to make ultra high energy cosmic rays. And some simulations, I know I'm being fuzzy again, some simulations suggest that they can, quote, accumulate excess magnetic energy in their cores.
Okay. So they're strong, they're powerful, they have strong magnetic fields. Good. They might be able to barf out the occasional in highly intense cosmic ray. The maybe.
I mean, the simulations just kind of suggest that, but, again, the physics are tough here. It's in a very high energy complicated regime. So it's not like our theories are painting a clear picture, and observations aren't painting a clear picture either because it's difficult to connect the original directions of the cosmic rays themselves to any particular source. There's not like you can look around the sky with different wavelengths and you can pick out the high energy sources, the steady, ready to go, always on sources, and it doesn't seem like the cosmic rays, the ultra high energy cosmic rays, are coming from any of those. So it's not just Centaurus a, but any strong continuous source that you might think might reliably produce cosmic rays probably produce some of these OMG particles, but it's definitely not all of them.
Nothing's obvious. Nothing is obvious as to the source of ultra high energy cosmic rays. So if none of the usual suspects are gonna work, are there any unusual suspects? Well, maybe it's weird stuff? Maybe there's some, I don't know, some relics from the early universe?
That sounds cool. Like a cosmological defect? If you'd like to hear more about cosmological defects, please ask. Love to dig into that. They're still floating around the universe, wrecking havoc, including generating ultra high energy cosmic rays.
Is it some form of exotic dark matter that 99 times out of a hundred doesn't interact with normal matter, but sometimes it does and generates in a in a high energy cosmic ray. Maybe, maybe not. There are plenty of ideas out there for generating high energy cosmic rays. They're all pretty hypothetical because in order to make that work, if you want to con concoct some scenario of crazy outlandish physics to make ultra high energy cosmic ray, it's gonna have other observable consequences like, I don't know, it might be the brightest radio source in the known universe, but then we don't see that. So you're like, well, I don't see that, so how can it not do that but also generate cosmic rays?
There are difficulties. Could it be maybe it's not a proton. We're pretty sure the OMG particle was a proton, but maybe not. Maybe it's heavier like iron. Iron, since it's heavier, it can plow through that cosmic microwave background without suffering ill effects, so it's not subject to that 60,000,000 light year limit.
But then how do you manufacture and accelerate an iron nucleus? Oh my gosh. OMG. It was already hard enough to make a proton that fast. How do you make an iron nucleus that fast?
Then the physics gets a little bit annoying. Maybe special relativity is broken. I mean, hey, come on. Just tossing out all the ideas. This whole distance limit thing assumes that we understand the mass energy relationship and the way that light interacts with particles.
That's all built on special relativity. Maybe special relativity is broken and the ultra high energy particles are trying to tell us something else. Like, Oh my gosh, Einstein was wrong. But special relativity holds up in every single other experiment and observation in the known universe, so it's hard to make a consistent picture there. Maybe it's something like flares?
Like, maybe active galactic nuclei. There's a bunch that are active right now, and we see them. Maybe the dormant ones that aren't so bright nowadays every once in a while, like, burp or get ingestion and have a flare. And in that episode, there's briefly the capabilities to generate an ultra high energy cosmic ray, and then it shuts off. So it makes a flash of light, makes some cosmic rays, and it says, okay, I'm done.
And then we don't see that because our surveys of studying these aren't equipped to look at short term things. We've mapped out all the constant steady sources, but not all the bleeps and bloops, but then we eventually catch a cosmic ray because we're able to capture these high energy things. Okay. You know, maybe that's kinda sorta plausible because that means the sources can be closer, maybe in parts of the sky we're not normally looking for cosmic rays, and it looks like the cosmic rays just come from all over. But it's kinda hard to pin down because, by definition, these events don't last long.
They're brief on the sky. We might get a better handle over the next couple decades. Astronomy is moving as a field is moving into what we call time domain astronomy, where we're not just looking at the sky as a constant unchanging portrait of our universe, but something that's alive and dynamic and changes over the course of hours or even minutes. And the more we can capture that hour to hour, night to night variation, the more interesting stuff we're gonna see. We're already seeing some interesting new results just in the past few years.
If you'd like to hear more, you know who to ask. Could it be that the answer for OMG particles is in bleeps and bloops and flares and transients and flashes and just, you know, crazy random stuff that's happening in the sky at really short timescales. We don't know. The ultimate question, what caused the OMG particle and what's caused its hundred or so friends that we've captured since then? We don't know.
That's it. We don't know. Thank you, Chris Scott on YouTube, for asking what is the OMG particle and giving me a chance to answer a question with a solid I don't know. Thank you so much for listening. Again, I'd like to thank my top Patreon contributors this month, Robert r, Justin g, Kevin o, Justin r, Chrissy, and Helga b.
It is your contributions and the contributions of all my supporters. They're keeping all of my education and outreach initiatives alive and thriving and growing. Deeply appreciative. Can't thank you enough. If you would like to talk about this on the radio show on Space Radio, go to spaceradioshow.com.
Record every Thursday at 4PM eastern. It's a call in show. It's tons of fun. It's a hot mess of a radio show, and I love every episode. So feel free to call in.
We can talk about this topic. And if you'd like to talk about it in person and say, I don't know, an exotic locale, go to astrotours.co and see all of our available trips. Thank you so much for watching. If you can, go on an Astro tour. If you don't wanna call in, if you don't wanna contribute to Patreon, that's fine.
We'll still be friends. Do me a favor and go to iTunes and leave a positive review. That helps get the show out so I can get more questions so I can keep doing episodes. I really enjoy doing these shows. Thank you so much for the opportunity to share all this cool science with you.
You can keep asking questions. Ask a space man dot com. Ask a spaceman@gmail.com. You can find me on Twitter, Facebook, and Instagram at paul matt sutter. Ask me questions there.
Use the hashtag ask spaceman or just ask me directly, and I'll see you next time for more complete knowledge of time and space.