I once shot my high powered blue laser at the space station while recording the live feed from the space station web cam on my computer and you could see a blue dot flashing from the ground. the problem is I was never able to recreate it so I dont know for sure if the flash was from me or something else. Edit: I just found the video, the quality is not great, in fact its rather bad since I had to download it off face book, but I'll email it to you.
Are the live feeds still active? Because I was watching a feed the other night, while also monitoring the ISS tracker website, and the images of the land the ISS was passing over didn't seem to match, so I guessed I was watching an old feed or something.
In a lab I work with a laser. The manual says the minimum eye-safe distance in the direction of the beam is 158km. I always wondered what that number might be good for.
I'm a pilot and have been lased a few times at night and it is quite annoying, but I can't say it's ever blinded me. The whole hand held nature just makes it flash randomly. These days though, with GPS we just tell ATC the lat/long or street address and they send the cops, 5 minutes later we can see a more satisfying kind of flashing lights :)
Seriously, don't point those green lasers at aircraft. I was the observer on a law enforcement helicopter for a number of years. We had one idiot paint us with a laser as we were orbiting over the scene of a murder and foot pursuit. The pilot was dazzled enough we had to break off the orbit until he regained his eyesight. Unfortunately for Laser Dude, we also had a GPS following the Night Sun searchlight, and we were able to light him up before we broke off. It took five patrol units about five minutes to have him custody after fighting with officers and doing the electric boogaloo for a couple minutes.. He served 4.5 years in prison on a combined state and federal felony charge. Just don't do it.
glad to hear they got what they deserved. i have a 200mw laser. but i am well aware of the dangers. (including the invisible wider spread beam you get with green lasers)
J Gregory Graves Some have more intellectual curiosity than others. Some of us like to read an entire book, or article, &some just wanna thumb through& look at pictures with captions.
Fail for the searchlights, though. And that was two 1-watt blue lasers. Green is much more visible to the eye, in terms of frequency response, but still doubtful that a single 5mW green laser would be visible from 500km into space. I'm sure the atmosphere would diffuse or filter most of that energy anyway.
_at least 10 others have too_ Not always. It's a fun theory but unproven. What it means is, "don't even bother trying," so those 10 become 0. Where would we be if it was always 0? The problem is caucasians are the founders of civilization and technology, who are also the worlds smallest minority. And people are upset we invent everything and want us to stop so they have a chance at getting 1. But they will always be 0. Social Darwinism.
+Cythil the experiment was for the search lights, as explained, the blue laser was only to align the search lights and was turned off to allow for the search lights to be seen. It's like experimental drug testing and only the control group lived, and calling it a good drug test. That's not a properly conducted experiment!
Again. Even when you get a negative result it is still a result Officer Meow Meow Fuzzyface. Then you know that the search lights in that setup won't cut it. Now I admit I have not read there research papers. But from what I can tell it was a resounding success that gave negative results. ^_^
When I lived in England, food deliveries could never find my house. So I would go outside and shine a green laser into the air for them to find me. It was a bit more powerful than a pointer.
Considering that every bit of laser you see as a line, is a bit of laser not getting through the atmospere, I would say "more than ideal for this purpose"
This question was on my mind throughout the entire video. I was expecting at least a rough estimate, in favorable weather conditions of course. Since anybody trying this would probably wait for a clear sky.
Also depending on altitude and pollution level. But given that the raw brightness under ideal conditions would be like Sirius: Even with 50% atmospheric absorption, it would still be easily visible.
Rule #1 Never point a laser at a person, auto, or aircraft. When I was studying Laser technology back in 1978 & 79 we had to memorize the safety rules concerning lasers and yep, it is #1!! Great Video Scott!!!
Scott, years back I was landing at KHYX at night. At the missed approach point, at 200 feet and a half mile out I noticed a car on the taxiway at the approach end of the runway. At that instant I got hit with a laser and lost all my vision. I was blind. Knowing that changing power or making any control inputs would cause the aircraft to become unstable I simply held the controls where they were and waited to impact the ground in a wings level, controlled descent rate (~300 fpm) At the last instant I saw a faint glow from a runway light in the lower corner of my right eye and flared. The arrival was firm but not violent. My wife had been looking away towards the lights of town still had her vision and she verbally steered us to the taxiway and back to the ramp. By then I was beginning to see faintly and I jumped out of the plane and was going looking for the drunk (probably) idiots. The wife physically held on to me as she knew what I intended to do. At a star party the young guys were firing a camera strobe light into the eyepiece of a 10" newtonian reflector. The bullets of light going up into space were mesmerizing. Dr. O
@ Manimozhian Kandasam, Exactly, atmosphere is the reason we see stars as freckles of light, something visibly "twinkling", instead of pure dots of light (which they are), or in worst case the atmosphere totally obstructs any light from the stars.
Even with all of that it can be seen. In fact- the 'space freaks' use a laser to deflect a laser off of the moon. As their are multiple mirror deflectors on the moon. Not you standard over the counter ones. These are bored people with money to spend. They can return and their laser sent up even though brief. So yes- it is more than plausible cause the ISS is nowhere near the distance of the moon. They can see traffic, lights, fires, with no real equipment from the ISS. Ham Operators make contact with them on the ISS with no beam as they pass over. Which is on the 100-400mhz bands. HF would have a dopplar effect and make contact even MORE likely. VHF/UHF has almost no propagation so with that being said. It would take a fixed laser to hit the space station. Take 500 feet of thread and make it straight between the 2. Then move the start of the thread 1/16th of a inch and see how far it misses at the end. By hand it would be VERY hard to hit and maintain. A fixed one with a telescope inline would work and be seen by the crew as well. There is footage of lasers hitting the ISS actually. Green one but of unknown power and focus.
Attenuation is not nearly as big a deal from the ground up as it is from space down, owing to the distance from the object that the intervening air is located at. There is another video on this, something like, what would pictures look like if you used hubble to take pictures of the ground.
Handheld would be tricky, but with an off the shelf LX200 telescope armed with my optical tracking software you would be able to keep a pointer centered on the station automatically and without needing any manual adjustment. As you mentioned, this has been done before with the astronaut in question being notified ahead of time that it was going to be happening. I wonder though if you encoded a laser to fire off a quick and simple 'Hi ISS' message in Morse code and diligently fired it at the station on every early evening or early morning opportunity, if they would eventually notice it by accident.
Could you program the mount to track the stations trajectory and at the right speed though ? As they are only designed to track at speed of the earths rotation I presume. TIA
So you are saying I need to make an arduino space station tracker, then add a 1 watt laser and make it blink in Morse code to an email account in hopes they will send me a message? Sounds like a plan.
As a light plane pilot, I have been lit up several times while landing. It appears as a very bright spot off to the side while flying. There is really only one thing that could cause that. Its only mildly annoying, but I also know there are much more powerful lasers out there you could buy.
I remember the first time I visited Walt Disney World (1998), they used a very powerful laser as part of their evening fireworks display. This amazingly bright thing was turned on only for a couple of seconds at a time, but was so bright that it "wrapped the horizon" from the perspective of the audience each time they activated it. My impression was that if it had hit an aircraft in flight, it probably would have blinded the flight crew for some indefinite period - as it was very bright. The next times I went back (2000, 2009), this super bright laser was no longer part of the fireworks show - which was probably a good thing, so it couldn't accidentally knock airplanes out of the sky if it happened to hit one.
When using lasers at that scale, and pointing it to the sky like that, you’ve talked with the nearby airports and/or the FAA beforehand to get it cleared. Those lasers can be up to 60W, so if the beam hits a pilot correctly, they could get permanent eye damage in under a second. Using lasers in 1998 required high voltage, water cooling, advanced software, and a lot of space, so they most likely dropped it because it was a hassle. I know this comment is 4 years old as of now, but felt like giving you an answer, haha.
S C I think the sun produces a bit more than 5mw of visible light. xD Srsly tho its amazing how little power is needed to transmit information across such distance. I dont know how much energy you would need to do the same with a radio but I assume a lot more and also you’d probably need a big antena on both ends.
Scott Major Yup, I've been hit once while flying an Arrow. Thankfully, it wasn't bad and I just went out and flew around the practice area for my region for about 30 minutes while my night vision returned. Reported it, but nothing ever came out of it.
Is it in any way likely that someone with a mirror or even a reflective wristwatch can use it to point it at a helicopter and actually be noticed? This is a survival tip I've heard a few times and always doubted until I saw this video.
Sheev Palpatine During daylight it needs to be really reflective (signal mirror) and the pilot has to be looking for it. I've seen those anti bird devices, that are basically mirrors spinning in the wind, on buildings from miles away, but it wasn't like they took my attention; more like I happened to look over there and noticed the strobe effect. At night, a strong flashlight is easily seen from miles. Just as you can see headlights miles away when up on a hill, the same thing applies. The difference is the "background". I can see you waiving a flashlight in the middle of nowhere with no other light sources much easier than if you were waiving the same flashlight at me from the center of Times Square.
MP I just had two reports from separate pilots out over the ocean say they were hit with lasers literally a few hours ago. I'm like, you are over the ocean right now, how is that even possible? We get reports quite frequently.
Yeah, I can confirm this happened with me. Naturally, all Lukes born are excellent aimers. Well, besides when I am using my telescope but that is because it has a cheap mount. I suppose the answer at the end of the day is you get what you pay for.... :(
You forgot to mention by how much you would need to lead the target. From my estimates I chose a 1200km round trip which is 4ms, and the station is going ~8km/s so you must lead by ~32m, which is much less than the beam diameter you calculated for that range. So that's not a problem either. Light is also refracted by the atmosphere but this effect basically cancels out if you are aiming visually at the ISS because optics works about the same backwards and forwards.
I know several people who've been lazed while flying an airplane. some weren't affected, but most had vision loss between a couple seconds and a several minutes. We even had to shut down flight operations to an airport after a pilot needed medical eye treatment due to a laser. Scott is right. Don't shine lasers at aircraft. Not only is it extremely dangerous to the flight crew, but if caught, you could face hefty fines and prison time. Also, it's really easy to fly over your position, get Lat/Long coordinates, and call the cops.
Tony Graham why would you watch a video on this topic if you weren’t looking for an explanation? If you were looking for a yes or a no, a simple google search would have sufficed- not an eight minute long video. This isn’t a tutorial with two minutes of irrelevant babbling at the start, it’s an explanation of something.
Pointing lasers at aircraft is not only a "bad idea," it is a federal offence that could land you in federal prison {no time off for "good behavior"), loose your right to vote, travel internationally, ever posses a firearm, or likely ever have a real job. Many Ebay or Alibaba lasers have power beyond legal limits. pointing one drunkenly at, for instance. a police helicopter, could change the arc of your life as dramatically as being busted as a meth dealer. Keep that in mind. The cops do.
Alberto Knox Just being the devil's advocate here: "What is a 'Federal Offence' or a 'Federal Prison' or 'time off for good behavior'?" Don't assume TH-cam is watched only/mainly by "USA" residents... Specially Science/Space Videos!. Just say "it's against the Law in the U.S.A." or something... Also: There's many more Countries with Laws against even Owning a Firearm than any Law against what You point Your Laser at (besides airplanes near airports - the most dangerous part of air travel is always taking off or landing) and even less against Owning a Laser Pointer. (One is actually used to kill things, the other one is just a "health hazard" ABOVE certain power levels, mostly to their owners who use it more, and an "annoyance" BELOW them - though MOST people who buy Stronger Lasers are Science minded people that would be careful to, at least, not inconvenience anyone with what they do, much less pointing it to aircraft On Purpose...) BTW: Most prisons in the World are part of "Public infrastructure" which means they're owned by the Countries' Government. Doesn't even make sense to have Privately Owned Prisons really... Specially when it's the Government, its Laws and its Judicial System that Puts people in them and, normally, only for serious Crimes that are actually considered dangerous to the Society/Population/Country... (Who wants to waste money on unnecessary things?...) And NO: Most Countries will NOT give any Less time in prison due to "Good Behavior"... But they WILL increase a Prison Sentence for (any) "Bad Conduit"... Bye then.
You're in the UK, right? You can spend 5 years in your "public infrastructure" for pointing a laser at any vehicle. That is only if you aren't charged with terrorism, which has in fact happened in your country.
These are good things to keep in mind, but also, as a pilot myself, since these thing often happen on approach, where you are looking at the ground in front of you, imagine trying to guide a big object that’s often being blown around by wind at a target only a few meters across while having big black spots burned into your vision. Just don’t shine lasers at aircraft people.
I have a small green light laser that is suppose to extend 20 miles thru the atmosphere- specifically for search and rescue. I would point it at an aircraft or boat if I was trying to get help in an emergency situation. As a field geologist I used to use a mirror to flash sunlight at the helicopter still several miles away. It worked very effectively (this was pre gps and pre walkie talkie).
You were trying to signal a helicopter pre walkie talkie? Did the helicopter have a flux capacitor and topped out at 88mph or you just didn’t know radios existed well before helicopters?
A few months ago I was looking out the passenger window on a night flight at 39000 feet, and someone on the ground started pointing a green laser at the airplane. At that altitude it was not near enough to blind or incapacitate but I was surprised how obvious it was what someone on the ground was doing even that high up.
There was an exploit on network equipment where you could read the data off of 10Mbit (or maybe it was 100MBit) Ethernet by pointing a sensor at the flickering light on the equipment display because they had hooked that light more or less directly up to the signal line. That was pretty nifty. If you could modulate the light from a laser pointer at high speed, it would be interesting to see what the bandwidth limit was. And that might have applications elsewhere. Space probes might be able to aim at earth accurately enough to use a direct line-of-sight laser for communication, and you could put one on them that had much lower beam divergence. Bandwidth to space probes is kind of limited. But that might be a way to increase it.
There is one small caveat to all of this. Those in the Western USA have relatively low humidity, clear skies much of the time. Not so much here in the Midwest, especially in the summer. Refraction of light due to air particulates, including humidity, could significantly scatter those photons enough to make seeing a laser light much more difficult from space.
As a pilot myself, thanks for emphasizing the danger of lasers to aircraft. I have been subjected to a laser illumination event, and I can tell you that if I hadn't covered my eyes as quickly as I had, I may have had permanent eye damage. As it was, I was able to land safely, but I will never forget the experience.
+Paul Kerman (Kerbonaut) hey there, I was wondering if you are at the maximum cruising altitude of 10.000 meters, and I point the laser in front of the airplane, let's say, 50 meters in front of it, and move it along as the airplane moves, would you be able to see it? If there would be some clouds I suppose you could, but if there wouldn't be?
Laser incidents seem to happen most near airports, and subsequently, critical phases of flight. A flight crew in the heaviest workload of the flight just doesn't need any surprises or distractions.
Thing is, cheap lasers for showing things in the sky are usually around 20 mW. San Antonio group did a 1 W laser. Yes, blue and therefore visually dimmer, but 1 W. That's some insane power for a handheld laser.
Yeah, it's not too insane though. You can get up to 6w handheld lasers online from places like pyrocreations. I've got the 3 watt and its pretty awesome, a lot brighter than my old 1w and 2w wicked lasers.
Yeah you really need to wear glasses for anything over 500mw no matter how careful you are being. That's just what I do though, you should probably wear glasses with any laser over 5mw but where's the fun in that lol
If I recall correctly, it seems that one of the Apollo 11 astronauts commented during their time on the moon that they suspect that they caught a glimpse of a high power laser that was trying to detect the retro-reflector that they had placed on the surface. I did take a college lab where we measured the distance from our location to both the Apollo 11 and Apollo 14 retro-reflectors, but we were using a pulsed UV laser that was several watts in strength (I don't remember exactly ... seems like 3W.) It is interesting to think that if our experiment would have been in the visible spectrum, it may have been visible from the Moon.
Corwin Christensen the first laser was actually bounced off the moon on May 9, in 1962 by MIT. Wait, What? 2629 days before man first set up the retro reflector on the moon to prove the NASA/"Mankind" was actually there. Kinda like those cameras in space that's always takes images of satellites and voyagers travelling through space.
@@vansfpv5198 Are you stupid? They were measuring their own light that they knew the wavelength of from a reflective body in space. The Moon always reflects the Sun, so if you set up your own laser and measure how much light comes back how is that unfeasible?
In college, my laser instructor Professor Jerry Hathaway tricked me and my classmate, Chris Knight, into building a laser weapon for the U.S. Air Force. By the time we found out, the laser had been mounted to a B1 Bomber. Fortunately, Lazlo Hollyfeld, the genius who lived in the walls figured out a way to fill Prof. Hathaways house with popcorn, so we aimed the laser there. As we watched Prof. Hathaways house burst from popcorn expansion, we froliced in the buttery treat in slow motion, accompanied by some moving 80's pop music (everybody, after all, wants to rule the world.). Sincerely; Mitch Taylor.
The practical engineering channel had a project called International space station tracker. It is a cool little project to make a machine that always points directly at the space station. I wonder how accurate that would be with a laser mounted on the arm.
Shortly after your comment was published, AI got more popular. So 4 years later, I have written an intro for you using GPT-4o just about what you asked. Title: Frequencies of Silence In the desolate expanse of the Xylian Cluster, where planets are little more than whispers in the dark, one world stands alone, its voice silenced by a relentless siege. Veridion, a once-thriving hub of interstellar trade and culture, now lies under the oppressive shadow of an impenetrable blockade. The skies, once filled with the vibrant comings and goings of starships, are now choked with the ominous presence of enemy dreadnoughts, their weapons trained on the surface below. Communication is a crime punishable by death; silence, a weapon wielded by the invaders to sever all ties between the planet and its allies in the heavens above. But in the depths of despair, resistance is born. Beneath the layers of concrete and steel, in the hidden enclaves of the city’s underground, a small group of rebels refuse to let their world be strangled into submission. They know that somewhere, beyond the blockade, their allies wait-desperate to hear a sign, a signal, anything to let them know that hope still burns on Veridion. And so, they turn to the most primitive of tools in this age of digital warfare: a simple laser pointer and the ancient language of Morse code. On the darkened rooftops of the city, in the dead of night, the rebels begin their dance with light and shadow. They send out their messages in short bursts of red light, flashing them into the void, praying that somewhere beyond the enemy fleet, their allies are watching. Every blink of the laser carries a word, a plea, a strategy, encoded in the staccato rhythm of dots and dashes. But this is not just a battle of technology; it is a battle of wits and endurance. The enemy is vigilant, their sensors sharp, hunting for the faintest whisper of rebellion. The rebels know that if they are discovered, the price will be their lives-and the last fragile thread connecting them to the outside world will be cut. Yet, they persist, using every trick in the book to evade detection: bouncing signals off debris in orbit, synchronizing their flashes with bursts of radiation from distant stars, and using the very darkness of space as their ally. It is a game of cat and mouse, with stakes that could determine the fate of an entire planet. As the blockade tightens and the enemy grows more desperate to quash the resistance, the rebels’ messages take on a new urgency. Supplies are running low, the population is growing restless, and rumors of betrayal swirl through the streets like poison. Yet, through it all, the laser continues to flicker in the night, a beacon of defiance against the encroaching darkness. But the question remains: can a handful of rebels, armed with nothing but a light and an ancient code, outwit an enemy that has mastered the art of war? And even if they can get their message through, will it be enough to turn the tide of a conflict that seems destined to end in silence? In Frequencies of Silence, the battle for Veridion is not just fought with ships and soldiers, but with ingenuity, courage, and the indomitable spirit of those who refuse to be silenced. In the cold vacuum of space, where words carry no sound, the flicker of a laser becomes the voice of a planet, crying out for salvation.
7:18: So they saw the 1W blue laser. BUT... that's 1 Watt. Not 5 mW. Big difference there. And the other question... how much of that 5 mW is going to be eaten up by the atmosphere?
Actually you couldn’t know for sure that there is a factor 200 for the blue laser for multiple reasons : the beam divergence is dependent of the wavelength, and thus being blue would diverge the blue laser even less compared to the green one. Actually the human eye is more sensitive to green light, so that would help seing more easily the green laser. A those altitude (500 km or so ) you would have minor absorption of light by the atmospheric gas, only the first two kilometer (close to the ground ) would absorb about half of the laser radiation, but being in the visible spectrum the factor would be the same for the blue and green. A more important issue would be the beam quality, for diode lasers of this kind( as laser pointer) the laser doesn’t have a round cross-section (meaning that pointing the laser to distance wall you could see that in fact it is not a round shaped spot, but more of a rectangle) so from there you would have a important factor taken from the energy sent. Another “point” is called the MTF (modulation transfer function), which is very important, in short if the contrast between the laser spot seen from space and the surroundings is not high enough and if the spot is too small, you might not be able to see anything. This effect can be seen when trying to see stars in crowed cities where the background (sky) is reflecting all the urban lights back towards the viewer, while going to remote places having “cleaner” skies allows for better sight. Sorry for being so long, I just really enjoyed the video.. keep it up!
Beam divergence is also dependent on the emitter type. Dpss, single mode diode, multi mode diode. The blue 1W laser diodes are multi mode and emit a wide line instead of a dot. This dramatically increases divergence of the laser light.
Yeah, I noticed that too. The 1W blue laser was bright enough I could believe seeing something of 0.5% the intensity though. And anybody with $200 can get a brand new 1W blue laser. For $300 you can get one that's 3.5W. Damn, this is reminding me how badly I want one....
This was so awesome Scott, I only wish I had some dorky friends to share my excitement with. It's hard being more forward thinking than everyone you know.
I modulated a cheap red laser pointer and used it to communicate with audio over a more than 100 mile path. The laser light from this cheap laser pointer was easily seen with our unaided eyes over thisc100+ mile pathm This also was through far more air and dust than between us and the ISS. It was hard to point it and we didn't have a moving target, but once on target, it was an easy path.
NASA uses lasers to track the moon (lasers and retro-reflectors on the moons surface) so surely we could annoy the ISS with a bright enough laser... Thanks for confirming that... :)
the beam width by the time it hits the moon is around 4 miles wide...now do the math you'll see not many photons hit their laser ranging devices on the surface of the moon.
If you see the space station it's some time just after dark, and from the station the area of the Earth you are in would be dark, so they might see a star light up from this area. Of course they probably already see a lot of city lights and things, so picking out a twinkle would be pretty hard. I wonder what the brightest things on the ground are that are seen from the space station.
Yeah and when those excited electrons fall back into their normal energy level, the release a new photon in a different direction, which will never end up in the space station.
The sun strength is about 1.36 kW/m2 right before hitting the atmosphere, and drops down to 1 kW/m2 after passing through the atmosphere, so assuming a similar absorption rate for the laser wavelength as the sun's total irradiance, only about 1/4 of the laser light would be absorbed.
That would make the experiment infinite times harder. You'd have to design, transport and mount that laser on the ISS. All they need up there is a handheld camera in this experiment.
Von Bergerfurth I don't think so with today's computers and calculations a fixed point on earth would surely be easier to calculate than than trying to calculate exactly the small pinpoint of a fast moving tiny dot.
@@Problembeing that fixed point on earth would be just as hard to track from the ISS as it is to track the ISS from earth, and it would cost millions of dollars.
Can I zoom radio satellite or television with telescope at higher orbits presumably it should stay static to where I zoom in since it orbits same direction earth rotates right?
If you illuminate a police helicopter around here, they have got very efficient at quickly finding out where the laser came from and send a patrol car out there.
I have a bright green laser that can mount on a rifle. If I point that at the space station will I get in trouble? I would be pointing a gun at people.
You are pointing a gun at people allthe time (through the earth when you are pointing it down), so probably not because this huge distance is basically an obstacle you can't overcome with a handheld gun. The bigger problem would be that bullets could hit people on the ground when they fall back down (don't know how dangerous this actually is).
Neat legal fact: In Germany, you could get in trouble if you assumed that you could shoot the ISS and actually tried to act on it; since even though your shot had no chance of hitting, it was based on a fundamentally valid theory of physics. The reason for this distinction is to differentiate between genuine murder attempts and people trying to say, hex or curse or wish others to death, because even given intent the law does not acknowledge magic as a plausible mechanism of murder. (So-called "superstitious attempted murder". )
I was present at that San Antonio Astronomy Association event and the blue laser was not robotically tracked but had a human operator on a mount to help it glide. There were no motors but was human powered.
basogoreng not much no. Not for green anyway. Blue would be a different story but our atmosphere is actually pretty clear (why we can even see stars) scattering happens but blue experienced severe Rayleigh scattering with blue wavelengths (can’t remember the exact wavelengths ) which is why it appears blue during the day
Hi Scott, how can you send a distress signal using a laser pointer, if you are caught unfortunately in those situations like plane crash on mountains or after jumping out of the sinking boat?
Very informative, Scott. Thank you. I use a green laser pointer in my back yard with my telescopes. I live within a mile of a regional airport and simply don't use it when aircraft are around.
Right, thought so. When you went on to say about the ISS being in the dark and hitting it's location I thought to myself it would be unlikely to be directly over you. So 500, could change quite a bit, but how much?
Something i often wondered, thank you Scott, i remember my kids having a little cheap red laser, i blew their minds with a 5Mw green laser which we could see on the high clouds in the night sky
I once shot my high powered blue laser at the space station while recording the live feed from the space station web cam on my computer and you could see a blue dot flashing from the ground. the problem is I was never able to recreate it so I dont know for sure if the flash was from me or something else. Edit: I just found the video, the quality is not great, in fact its rather bad since I had to download it off face book, but I'll email it to you.
That's pretty neat! I might have to try that for myself one night.
Did you recover the photons that were dissolved in the atmosphere in the process? :)
Could you post a link here as well?
Oh you could phase-modulate the laser and use that to confirm the distance to the space station, that would be cool.
Are the live feeds still active? Because I was watching a feed the other night, while also monitoring the ISS tracker website, and the images of the land the ISS was passing over didn't seem to match, so I guessed I was watching an old feed or something.
As an airline pilot, once again please do not shine them at me.
Is that your excuse for 9/11?
@@SteveVi0lence lmao
Sure Captain Twat...
SteveVi0lence lmao
@@SteveVi0lence lmao
Answer to video title:
YES, IF IT'S MADE BY STYROPYRO.
Illuminate the ISS?
This sounds like a job for Styropyro!
@THE AMAZING SPIDER-MAN more like the láser god
He´ll burn straight through the ISS :D
Don't give him this challenge, he will try to pop it with a laser ;-(
He will melt a hole in the wall :P
He would laugh at 5mw
Expected a "no" got a "yes".
Answers at 6:42
Joe thx
In a lab I work with a laser. The manual says the minimum eye-safe distance in the direction of the beam is 158km. I always wondered what that number might be good for.
Who else is just scrolling through comments whilst he chats away, until you reach someone's comment directing you to the answer Yes at 6:50?
Me! Thank you.
Well someone had to say it
God Bless You child.
Me
Thank you kindly!
I'm a pilot and have been lased a few times at night and it is quite annoying, but I can't say it's ever blinded me. The whole hand held nature just makes it flash randomly. These days though, with GPS we just tell ATC the lat/long or street address and they send the cops, 5 minutes later we can see a more satisfying kind of flashing lights :)
So glad to hear from a objective pilot with a real experience 😅 thank you for your time
@@lusiscuswho is your comment aimed at? I have trouble working out who is replying to who😢
@@CraigLandsberg-lk1ep hmmmmm, I think I have somehow posted on the wrong video, I do apologise.
Seriously, don't point those green lasers at aircraft. I was the observer on a law enforcement helicopter for a number of years. We had one idiot paint us with a laser as we were orbiting over the scene of a murder and foot pursuit. The pilot was dazzled enough we had to break off the orbit until he regained his eyesight. Unfortunately for Laser Dude, we also had a GPS following the Night Sun searchlight, and we were able to light him up before we broke off. It took five patrol units about five minutes to have him custody after fighting with officers and doing the electric boogaloo for a couple minutes.. He served 4.5 years in prison on a combined state and federal felony charge. Just don't do it.
Sar Jim Damn!!!
glad to hear they got what they deserved.
i have a 200mw laser. but i am well aware of the dangers. (including the invisible wider spread beam you get with green lasers)
4.5 years??? BS.. messing around with a laser shouldn’t net you any longer than a few months jail time
@@drifterax7731 blinding a pilot thats flying a plane with 300 people is pretty bad
@Håkan Lundberg the problem is that this generally happens during landing. not exactly a time you want to be blinding a pilot is it?
Despite all the complaining about how long this video is I loved all of it and I appreciated the entire explanation. Thank you for sharing.
J Gregory Graves Some have more intellectual curiosity than others. Some of us like to read an entire book, or article, &some just wanna thumb through& look at pictures with captions.
@@Chief2Moon Yep, it's what makes the world go round... so to speak : )
8 minutes is pretty short
They should just Google it. Then the answer is instant 😉.
Long? It's only 8 minutes
* puts on black hat *
What if we tried more power?
Paul Paulson school lazerings would happen
I read this in Will Wheaton's voice because he was the reader for the Audiobook "What If".
what if we CROSS THE BEAM!
Look at Isaac Arthur channel, idk the exact video, it's one of the space warfare, stating why lasers as space weapons are a bad idea and useless...
I knew I'd find a comment like that somewhere, hah
The picture of the laser aimed at the space station from the ground was pretty neat. Glad someone made this experiment. ^_^
Fail for the searchlights, though. And that was two 1-watt blue lasers. Green is much more visible to the eye, in terms of frequency response, but still doubtful that a single 5mW green laser would be visible from 500km into space. I'm sure the atmosphere would diffuse or filter most of that energy anyway.
There is not really such a thing as a fail when it comes to properly conducted experiments. Just positive or negative results ;)
_at least 10 others have too_
Not always. It's a fun theory but unproven. What it means is, "don't even bother trying," so those 10 become 0. Where would we be if it was always 0? The problem is caucasians are the founders of civilization and technology, who are also the worlds smallest minority. And people are upset we invent everything and want us to stop so they have a chance at getting 1. But they will always be 0. Social Darwinism.
+Cythil the experiment was for the search lights, as explained, the blue laser was only to align the search lights and was turned off to allow for the search lights to be seen. It's like experimental drug testing and only the control group lived, and calling it a good drug test. That's not a properly conducted experiment!
Again. Even when you get a negative result it is still a result Officer Meow Meow Fuzzyface. Then you know that the search lights in that setup won't cut it. Now I admit I have not read there research papers. But from what I can tell it was a resounding success that gave negative results. ^_^
Well.. If it is illegal to dazzle parties, I'll just stay at home.
Such a great comment...
best comment.
I came
👍
Your comment pleases me.
When I lived in England, food deliveries could never find my house. So I would go outside and shine a green laser into the air for them to find me. It was a bit more powerful than a pointer.
*ISS explodes
you had aeriel food delivery?
@@natesmartkid6493 You could see the laser from ground level from over a mile away.
@@scottd9448 yup. I live in an apartment (4 stories) and shit mate I could shine towards those skyscrapers
That's assault, you can get arrested for that, consider yourself lucky and never do something like that ever again
What about pointing to geostationary weather satellites? They are far away (36 000 km), but you could aim precisely with many pointers ...
But how much of the light would be obstructed in the atmosphere?
Somewhere between 0.1% and 100% depending on the weather.
LOL, actually the most accurate answer that can be given!
Considering that every bit of laser you see as a line, is a bit of laser not getting through the atmospere, I would say "more than ideal for this purpose"
This question was on my mind throughout the entire video. I was expecting at least a rough estimate, in favorable weather conditions of course. Since anybody trying this would probably wait for a clear sky.
Also depending on altitude and pollution level. But given that the raw brightness under ideal conditions would be like Sirius: Even with 50% atmospheric absorption, it would still be easily visible.
So I could grab my 2.5 watt laser, and send a message to iss saying:
S E N D N U D E S
Beware Cthulhu
Michal
for berevity
I suggest:
SND NOODS
Would be faster/easier to send in morse.
stinkyfungus tru
post bobs
Or perhaps more fitting would be:
T R A N S M I T N U D E S
but its longer
Rule #1 Never point a laser at a person, auto, or aircraft. When I was studying Laser technology back in 1978 & 79 we had to memorize the safety rules concerning lasers and yep, it is #1!! Great Video Scott!!!
What about self defense
Scott, years back I was landing at KHYX at night. At the missed approach point, at 200 feet and a half mile out I noticed a car on the taxiway at the approach end of the runway. At that instant I got hit with a laser and lost all my vision. I was blind. Knowing that changing power or making any control inputs would cause the aircraft to become unstable I simply held the controls where they were and waited to impact the ground in a wings level, controlled descent rate (~300 fpm) At the last instant I saw a faint glow from a runway light in the lower corner of my right eye and flared. The arrival was firm but not violent. My wife had been looking away towards the lights of town still had her vision and she verbally steered us to the taxiway and back to the ramp. By then I was beginning to see faintly and I jumped out of the plane and was going looking for the drunk (probably) idiots. The wife physically held on to me as she knew what I intended to do.
At a star party the young guys were firing a camera strobe light into the eyepiece of a 10" newtonian reflector. The bullets of light going up into space were mesmerizing.
Dr. O
You didn't consider one important factor: atmospheric attenuation. Lot of photons will be absorbed by air and moisture. Correct?
Manimozhian Kandasamy correct
I know right
@
Manimozhian Kandasam, Exactly, atmosphere is the reason we see stars as freckles of light, something visibly "twinkling", instead of pure dots of light (which they are), or in worst case the atmosphere totally obstructs any light from the stars.
Even with all of that it can be seen. In fact- the 'space freaks' use a laser to deflect a laser off of the moon. As their are multiple mirror deflectors on the moon. Not you standard over the counter ones. These are bored people with money to spend. They can return and their laser sent up even though brief. So yes- it is more than plausible cause the ISS is nowhere near the distance of the moon. They can see traffic, lights, fires, with no real equipment from the ISS. Ham Operators make contact with them on the ISS with no beam as they pass over. Which is on the 100-400mhz bands. HF would have a dopplar effect and make contact even MORE likely. VHF/UHF has almost no propagation so with that being said. It would take a fixed laser to hit the space station. Take 500 feet of thread and make it straight between the 2. Then move the start of the thread 1/16th of a inch and see how far it misses at the end. By hand it would be VERY hard to hit and maintain. A fixed one with a telescope inline would work and be seen by the crew as well. There is footage of lasers hitting the ISS actually. Green one but of unknown power and focus.
Attenuation is not nearly as big a deal from the ground up as it is from space down, owing to the distance from the object that the intervening air is located at. There is another video on this, something like, what would pictures look like if you used hubble to take pictures of the ground.
Handheld would be tricky, but with an off the shelf LX200 telescope armed with my optical tracking software you would be able to keep a pointer centered on the station automatically and without needing any manual adjustment. As you mentioned, this has been done before with the astronaut in question being notified ahead of time that it was going to be happening. I wonder though if you encoded a laser to fire off a quick and simple 'Hi ISS' message in Morse code and diligently fired it at the station on every early evening or early morning opportunity, if they would eventually notice it by accident.
Astronomy Live .... .. .. ... ...
All dots
Astronomy Live Do it, please!
And use a bigass laser atleast 1w green.
Could you program the mount to track the stations trajectory and at the right speed though ? As they are only designed to track at speed of the earths rotation I presume. TIA
Communications are down. Get the laser guys.
Never mind the lasers; call the hams. There is amateur radio onboard the ISS, and they use that to communicate when the fancy stuff goes pear-shaped.
So you are saying I need to make an arduino space station tracker, then add a 1 watt laser and make it blink in Morse code to an email account in hopes they will send me a message?
Sounds like a plan.
6:25 ayy that's a cool effect
funny thing is, that's just an old camera mounted on the ISS :P
Yeah, i admit very nicely computer generated sunset.
As a light plane pilot, I have been lit up several times while landing. It appears as a very bright spot off to the side while flying. There is really only one thing that could cause that. Its only mildly annoying, but I also know there are much more powerful lasers out there you could buy.
Was it a red one?
I remember the first time I visited Walt Disney World (1998), they used a very powerful laser as part of their evening fireworks display. This amazingly bright thing was turned on only for a couple of seconds at a time, but was so bright that it "wrapped the horizon" from the perspective of the audience each time they activated it. My impression was that if it had hit an aircraft in flight, it probably would have blinded the flight crew for some indefinite period - as it was very bright. The next times I went back (2000, 2009), this super bright laser was no longer part of the fireworks show - which was probably a good thing, so it couldn't accidentally knock airplanes out of the sky if it happened to hit one.
When using lasers at that scale, and pointing it to the sky like that, you’ve talked with the nearby airports and/or the FAA beforehand to get it cleared. Those lasers can be up to 60W, so if the beam hits a pilot correctly, they could get permanent eye damage in under a second. Using lasers in 1998 required high voltage, water cooling, advanced software, and a lot of space, so they most likely dropped it because it was a hassle.
I know this comment is 4 years old as of now, but felt like giving you an answer, haha.
And now it's even cheaper since you don't have to talk to FAA, just fire up Flightradar24 and watch out for planes lol
Jaw is legit floored open right now... I actually had _no idea_ that laser light could still be _that_ visible at _that_ range... Amazing.
Everything is better with lasers.
L.D. Johnson you do realize that 300-400km is not that much of a range?)) and you do see photons arriving from the Sun, right?)
ditto
S C I think the sun produces a bit more than 5mw of visible light. xD
Srsly tho its amazing how little power is needed to transmit information across such distance. I dont know how much energy you would need to do the same with a radio but I assume a lot more and also you’d probably need a big antena on both ends.
Thx, Scott for reminding everyone not to point those lasers at aircraft. You'd be amazed how often it still happens, especially on approach. :)
Scott Major Yup, I've been hit once while flying an Arrow. Thankfully, it wasn't bad and I just went out and flew around the practice area for my region for about 30 minutes while my night vision returned. Reported it, but nothing ever came out of it.
Is it in any way likely that someone with a mirror or even a reflective wristwatch can use it to point it at a helicopter and actually be noticed? This is a survival tip I've heard a few times and always doubted until I saw this video.
Sheev Palpatine During daylight it needs to be really reflective (signal mirror) and the pilot has to be looking for it. I've seen those anti bird devices, that are basically mirrors spinning in the wind, on buildings from miles away, but it wasn't like they took my attention; more like I happened to look over there and noticed the strobe effect.
At night, a strong flashlight is easily seen from miles. Just as you can see headlights miles away when up on a hill, the same thing applies. The difference is the "background". I can see you waiving a flashlight in the middle of nowhere with no other light sources much easier than if you were waiving the same flashlight at me from the center of Times Square.
MP I just had two reports from separate pilots out over the ocean say they were hit with lasers literally a few hours ago. I'm like, you are over the ocean right now, how is that even possible? We get reports quite frequently.
FriskyDingo it must be Atlantis or people at ISS on their resting time.
There is absolutely no reason I need to know this information. I enjoyed it thoroughly all the same. Thanks for that 😁👍.
I used to shoot womp rats with my t16 back home so nailing that space station with a green Lazer should be easy....
@Mag yep... you need to turn on the targeting computer!
Aww nothing like an old Luke Skywalker line from the movie Star Wars to make a joke! Good job, I like it!
🤣🤣🤣
Jeff somersby yeah i used to shoot ants with a tank back in the old country
Yeah, I can confirm this happened with me. Naturally, all Lukes born are excellent aimers. Well, besides when I am using my telescope but that is because it has a cheap mount. I suppose the answer at the end of the day is you get what you pay for.... :(
Stay on target
Don't aim a laser at some satellite that might be able to respond in kind but with 1000x the power ..
en.wikipedia.org/wiki/Polyus_(spacecraft)
That's OK, I only aim at small moons
just make sure its a moon
My small moon aims it laser at MC-80s....
Paul Weaver. That's no moon, it's a space station!
You forgot to mention by how much you would need to lead the target. From my estimates I chose a 1200km round trip which is 4ms, and the station is going ~8km/s so you must lead by ~32m, which is much less than the beam diameter you calculated for that range. So that's not a problem either.
Light is also refracted by the atmosphere but this effect basically cancels out if you are aiming visually at the ISS because optics works about the same backwards and forwards.
Took the words right out of my mouth, and you took the time to calculate it! Well done sir!
someone gets it yes sir! exactly, this is a year old ...if you see this? read my comment it's last one im sure lol
He didn't forget to mention it. It is simply irrelevant. He also didn't mention correcting for time dilation either and for the same reason.
This was THE most interesting thing TH-cam has recommended to me in a long time.👍👍
I know several people who've been lazed while flying an airplane. some weren't affected, but most had vision loss between a couple seconds and a several minutes. We even had to shut down flight operations to an airport after a pilot needed medical eye treatment due to a laser. Scott is right. Don't shine lasers at aircraft. Not only is it extremely dangerous to the flight crew, but if caught, you could face hefty fines and prison time. Also, it's really easy to fly over your position, get Lat/Long coordinates, and call the cops.
6:50 6 minutes and 50 seconds to get a definitive yes XD
Lol ikr! Stop babbling and get to the point!
@@LOLmusics boo hoo
Josh 😭 😢 😭:( :( 😖😖😖😭😭😭😤😤😔😢😢😭😭
@@LOLmusics you already said that, cutie pie
Tony Graham why would you watch a video on this topic if you weren’t looking for an explanation? If you were looking for a yes or a no, a simple google search would have sufficed- not an eight minute long video. This isn’t a tutorial with two minutes of irrelevant babbling at the start, it’s an explanation of something.
Pointing lasers at aircraft is not only a "bad idea," it is a federal offence that could land you in federal prison {no time off for "good behavior"), loose your right to vote, travel internationally, ever posses a firearm, or likely ever have a real job. Many Ebay or Alibaba lasers have power beyond legal limits. pointing one drunkenly at, for instance. a police helicopter, could change the arc of your life as dramatically as being busted as a meth dealer. Keep that in mind. The cops do.
Alberto Knox
Just being the devil's advocate here:
"What is a 'Federal Offence' or a 'Federal Prison' or 'time off for good behavior'?"
Don't assume TH-cam is watched only/mainly by "USA" residents... Specially Science/Space Videos!.
Just say "it's against the Law in the U.S.A." or something...
Also:
There's many more Countries with Laws against even Owning a Firearm than any Law against what You point Your Laser at (besides airplanes near airports - the most dangerous part of air travel is always taking off or landing) and even less against Owning a Laser Pointer.
(One is actually used to kill things, the other one is just a "health hazard" ABOVE certain power levels, mostly to their owners who use it more, and an "annoyance" BELOW them - though MOST people who buy Stronger Lasers are Science minded people that would be careful to, at least, not inconvenience anyone with what they do, much less pointing it to aircraft On Purpose...)
BTW:
Most prisons in the World are part of "Public infrastructure" which means they're owned by the Countries' Government.
Doesn't even make sense to have Privately Owned Prisons really... Specially when it's the Government, its Laws and its Judicial System that Puts people in them and, normally, only for serious Crimes that are actually considered dangerous to the Society/Population/Country...
(Who wants to waste money on unnecessary things?...)
And NO: Most Countries will NOT give any Less time in prison due to "Good Behavior"... But they WILL increase a Prison Sentence for (any) "Bad Conduit"...
Bye then.
You're in the UK, right? You can spend 5 years in your "public infrastructure" for pointing a laser at any vehicle. That is only if you aren't charged with terrorism, which has in fact happened in your country.
These are good things to keep in mind, but also, as a pilot myself, since these thing often happen on approach, where you are looking at the ground in front of you, imagine trying to guide a big object that’s often being blown around by wind at a target only a few meters across while having big black spots burned into your vision. Just don’t shine lasers at aircraft people.
that's if they don't just flat out shoot them dead for "threatening" them
Bill Kerr
In the nethelands those high powered green laser pointers have been banned after a plane got blinded by one of them
so, a 5mw laser would be as bright as sirius, how would a 100 or 1000mw laser look like?
Brighter.
lol, you are technically correct. I was wondering how much.
Ask the people of Alderaan.
Wait, you can't... they're dead.
You're talking about weapons now, not just a laser pointer anymore.
Rocket scientist: NEED MOAR BOASTERS !!!
Physicist: NEED MOAR POAWER !!!
7:35 if you just want the answer
CJ Bants-THANK YOU
He was killing me 🥱......thanks
thanks
CJ Bants thanks
I have a small green light laser that is suppose to extend 20 miles thru the atmosphere- specifically for search and rescue. I would point it at an aircraft or boat if I was trying to get help in an emergency situation. As a field geologist I used to use a mirror to flash sunlight at the helicopter still several miles away. It worked very effectively (this was pre gps and pre walkie talkie).
You were trying to signal a helicopter pre walkie talkie? Did the helicopter have a flux capacitor and topped out at 88mph or you just didn’t know radios existed well before helicopters?
A few months ago I was looking out the passenger window on a night flight at 39000 feet, and someone on the ground started pointing a green laser at the airplane. At that altitude it was not near enough to blind or incapacitate but I was surprised how obvious it was what someone on the ground was doing even that high up.
This is one of the coolest videos I've seen in a while
There was an exploit on network equipment where you could read the data off of 10Mbit (or maybe it was 100MBit) Ethernet by pointing a sensor at the flickering light on the equipment display because they had hooked that light more or less directly up to the signal line. That was pretty nifty. If you could modulate the light from a laser pointer at high speed, it would be interesting to see what the bandwidth limit was.
And that might have applications elsewhere. Space probes might be able to aim at earth accurately enough to use a direct line-of-sight laser for communication, and you could put one on them that had much lower beam divergence. Bandwidth to space probes is kind of limited. But that might be a way to increase it.
Seen ppl did that hardware magic before, it is not ok for daily usage though, since the frame we loss is atrocious.
Laser communication exists and is mainly used for communication between satellites (starlink for example uses it)
2 videos this quickly? Wow.
There is one small caveat to all of this. Those in the Western USA have relatively low humidity, clear skies much of the time. Not so much here in the Midwest, especially in the summer. Refraction of light due to air particulates, including humidity, could significantly scatter those photons enough to make seeing a laser light much more difficult from space.
I can see this becoming more popular and the ISS being bombarded with green lasers, the cat is out of the bag.
As a pilot myself, thanks for emphasizing the danger of lasers to aircraft. I have been subjected to a laser illumination event, and I can tell you that if I hadn't covered my eyes as quickly as I had, I may have had permanent eye damage. As it was, I was able to land safely, but I will never forget the experience.
How high off the ground were you?
I was about 2000 feet above the ground climbing out after doing a touch and go in Ponca City, OK
+Paul Kerman (Kerbonaut) hey there, I was wondering if you are at the maximum cruising altitude of 10.000 meters, and I point the laser in front of the airplane, let's say, 50 meters in front of it, and move it along as the airplane moves, would you be able to see it? If there would be some clouds I suppose you could, but if there wouldn't be?
This is the same scenario as the above video, just on a smaller scale. Again, aiming lasers at aircraft is NEVER a good idea.
Laser incidents seem to happen most near airports, and subsequently, critical phases of flight. A flight crew in the heaviest workload of the flight just doesn't need any surprises or distractions.
Thing is, cheap lasers for showing things in the sky are usually around 20 mW. San Antonio group did a 1 W laser. Yes, blue and therefore visually dimmer, but 1 W. That's some insane power for a handheld laser.
Yeah, it's not too insane though. You can get up to 6w handheld lasers online from places like pyrocreations. I've got the 3 watt and its pretty awesome, a lot brighter than my old 1w and 2w wicked lasers.
You can buy all the components and put one together for pretty cheap. My 1.8 watt handheld was around $140.
Yeah you really need to wear glasses for anything over 500mw no matter how careful you are being. That's just what I do though, you should probably wear glasses with any laser over 5mw but where's the fun in that lol
I bought one on Ebay that'll light your cigarette or yer doobage no probby.
Standard
If I recall correctly, it seems that one of the Apollo 11 astronauts commented during their time on the moon that they suspect that they caught a glimpse of a high power laser that was trying to detect the retro-reflector that they had placed on the surface. I did take a college lab where we measured the distance from our location to both the Apollo 11 and Apollo 14 retro-reflectors, but we were using a pulsed UV laser that was several watts in strength (I don't remember exactly ... seems like 3W.) It is interesting to think that if our experiment would have been in the visible spectrum, it may have been visible from the Moon.
Corwin Christensen the first laser was actually bounced off the moon on May 9, in 1962 by MIT.
Wait, What? 2629 days before man first set up the retro reflector on the moon to prove the NASA/"Mankind" was actually there.
Kinda like those cameras in space that's always takes images of satellites and voyagers travelling through space.
@@vansfpv5198 Are you stupid? They were measuring their own light that they knew the wavelength of from a reflective body in space. The Moon always reflects the Sun, so if you set up your own laser and measure how much light comes back how is that unfeasible?
I haven't heard that before, but I have heard that Buzz Aldrin saw flashes which he didn't understand at the time, turned out to be cosmic rays.
What camera did he use to film the space station going in front of the sun?
If you use a beam expander, you can greatly reduce the divergence.
Only in the near field. To get the near field to extend 600 km would take a beam expander lens 6km wide.
In college, my laser instructor Professor Jerry Hathaway tricked me and my classmate, Chris Knight, into building a laser weapon for the U.S. Air Force. By the time we found out, the laser had been mounted to a B1 Bomber. Fortunately, Lazlo Hollyfeld, the genius who lived in the walls figured out a way to fill Prof. Hathaways house with popcorn, so we aimed the laser there.
As we watched Prof. Hathaways house burst from popcorn expansion, we froliced in the buttery treat in slow motion, accompanied by some moving 80's pop music (everybody, after all, wants to rule the world.).
Sincerely;
Mitch Taylor.
I’ve seen the video evidence supporting this moment of real genius.
Link????
I remember that movie - Real Genius!
Sir have you have had any interactions with uhh _marijuana_
And by the look of him now Val Kilmer ate all the popcorn afterwards.
I was very impressed with the space station against the sun!
I don’t know why but I literally felt like I could listen to this guy talk all day lol. Nice delivery and very interesting
I don’t know why I really needed to know this but searched for it and you answered it perfectly, thanks!
Now invert the idea and imagine how powerful the stars visible at earth are
Just amazing !!
don't your calculations assume the photons are traveling through a vacuum? and thus would the atmospheric interference impede the laser light?
Scatter the light as it is refracting off trillions of dust particles and water molecules...
The practical engineering channel had a project called International space station tracker. It is a cool little project to make a machine that always points directly at the space station. I wonder how accurate that would be with a laser mounted on the arm.
Lol add styropyros laser bazooka
Thanks for shining a light on the subject.
What about the light that is absorded/scattered by the atmosphere ? (since we se the path of the laser, that must be non negligable)
Now I want an SF story where people on a blockaded planet communicate with allies in orbit using morse code and a laser pointer...
Start writing it.....
Shortly after your comment was published, AI got more popular. So 4 years later, I have written an intro for you using GPT-4o just about what you asked.
Title: Frequencies of Silence
In the desolate expanse of the Xylian Cluster, where planets are little more than whispers in the dark, one world stands alone, its voice silenced by a relentless siege. Veridion, a once-thriving hub of interstellar trade and culture, now lies under the oppressive shadow of an impenetrable blockade. The skies, once filled with the vibrant comings and goings of starships, are now choked with the ominous presence of enemy dreadnoughts, their weapons trained on the surface below. Communication is a crime punishable by death; silence, a weapon wielded by the invaders to sever all ties between the planet and its allies in the heavens above.
But in the depths of despair, resistance is born. Beneath the layers of concrete and steel, in the hidden enclaves of the city’s underground, a small group of rebels refuse to let their world be strangled into submission. They know that somewhere, beyond the blockade, their allies wait-desperate to hear a sign, a signal, anything to let them know that hope still burns on Veridion. And so, they turn to the most primitive of tools in this age of digital warfare: a simple laser pointer and the ancient language of Morse code.
On the darkened rooftops of the city, in the dead of night, the rebels begin their dance with light and shadow. They send out their messages in short bursts of red light, flashing them into the void, praying that somewhere beyond the enemy fleet, their allies are watching. Every blink of the laser carries a word, a plea, a strategy, encoded in the staccato rhythm of dots and dashes. But this is not just a battle of technology; it is a battle of wits and endurance. The enemy is vigilant, their sensors sharp, hunting for the faintest whisper of rebellion.
The rebels know that if they are discovered, the price will be their lives-and the last fragile thread connecting them to the outside world will be cut. Yet, they persist, using every trick in the book to evade detection: bouncing signals off debris in orbit, synchronizing their flashes with bursts of radiation from distant stars, and using the very darkness of space as their ally. It is a game of cat and mouse, with stakes that could determine the fate of an entire planet.
As the blockade tightens and the enemy grows more desperate to quash the resistance, the rebels’ messages take on a new urgency. Supplies are running low, the population is growing restless, and rumors of betrayal swirl through the streets like poison. Yet, through it all, the laser continues to flicker in the night, a beacon of defiance against the encroaching darkness.
But the question remains: can a handful of rebels, armed with nothing but a light and an ancient code, outwit an enemy that has mastered the art of war? And even if they can get their message through, will it be enough to turn the tide of a conflict that seems destined to end in silence?
In Frequencies of Silence, the battle for Veridion is not just fought with ships and soldiers, but with ingenuity, courage, and the indomitable spirit of those who refuse to be silenced. In the cold vacuum of space, where words carry no sound, the flicker of a laser becomes the voice of a planet, crying out for salvation.
7:18: So they saw the 1W blue laser. BUT... that's 1 Watt. Not 5 mW. Big difference there.
And the other question... how much of that 5 mW is going to be eaten up by the atmosphere?
1Watt laser would be 200x brighter, so it would be ~ magitude -8
Actually you couldn’t know for sure that there is a factor 200 for the blue laser for multiple reasons : the beam divergence is dependent of the wavelength, and thus being blue would diverge the blue laser even less compared to the green one.
Actually the human eye is more sensitive to green light, so that would help seing more easily the green laser.
A those altitude (500 km or so ) you would have minor absorption of light by the atmospheric gas, only the first two kilometer (close to the ground ) would absorb about half of the laser radiation, but being in the visible spectrum the factor would be the same for the blue and green.
A more important issue would be the beam quality, for diode lasers of this kind( as laser pointer) the laser doesn’t have a round cross-section (meaning that pointing the laser to distance wall you could see that in fact it is not a round shaped spot, but more of a rectangle) so from there you would have a important factor taken from the energy sent.
Another “point” is called the MTF (modulation transfer function), which is very important, in short if the contrast between the laser spot seen from space and the surroundings is not high enough and if the spot is too small, you might not be able to see anything. This effect can be seen when trying to see stars in crowed cities where the background (sky) is reflecting all the urban lights back towards the viewer, while going to remote places having “cleaner” skies allows for better sight.
Sorry for being so long, I just really enjoyed the video.. keep it up!
Scott Manley dimmer than σ Octantis...
Beam divergence is also dependent on the emitter type. Dpss, single mode diode, multi mode diode. The blue 1W laser diodes are multi mode and emit a wide line instead of a dot. This dramatically increases divergence of the laser light.
Yeah, I noticed that too. The 1W blue laser was bright enough I could believe seeing something of 0.5% the intensity though. And anybody with $200 can get a brand new 1W blue laser. For $300 you can get one that's 3.5W. Damn, this is reminding me how badly I want one....
This was so awesome Scott, I only wish I had some dorky friends to share my excitement with. It's hard being more forward thinking than everyone you know.
What if you reflect converged sunlight to ISS?
I modulated a cheap red laser pointer and used it to communicate with audio over a more than 100 mile path. The laser light from this cheap laser pointer was easily seen with our unaided eyes over thisc100+ mile pathm This also was through far more air and dust than between us and the ISS. It was hard to point it and we didn't have a moving target, but once on target, it was an easy path.
NASA uses lasers to track the moon (lasers and retro-reflectors on the moons surface) so surely we could annoy the ISS with a bright enough laser...
Thanks for confirming that... :)
the beam width by the time it hits the moon is around 4 miles wide...now do the math you'll see not many photons hit their laser ranging devices on the surface of the moon.
Have we been blinding extraterrestrial air planes this whole time?
Cheap laser: $10, wow
Wait, robotic aram: $1000000
I have bought laser for 3$, so the laser is even cheaper :P
A nice GoTo telescope mount with satellite tracking ability shouldn't be that expensive.
5:23 that was an amazing shot. thank you for slowing it down and zooming in
If you see the space station it's some time just after dark, and from the station the area of the Earth you are in would be dark, so they might see a star light up from this area. Of course they probably already see a lot of city lights and things, so picking out a twinkle would be pretty hard. I wonder what the brightest things on the ground are that are seen from the space station.
9 minutes on a yes or no question, but still thanks for answering 🙃
It's not a yes or no question just a simple yes or no doesn't really tell you anything does it
won't some photons also be absorbed by air molecules ?
ZockerTwins no?) does your skin 'absorb' light? So woould yoy be invisible while tanning?))) you just have different reflectivity and so does air )
S C No he is correct, the electrons in oxygens atoms can absorb photons and reach an excited state
Yeah and when those excited electrons fall back into their normal energy level, the release a new photon in a different direction, which will never end up in the space station.
The sun strength is about 1.36 kW/m2 right before hitting the atmosphere, and drops down to 1 kW/m2 after passing through the atmosphere, so assuming a similar absorption rate for the laser wavelength as the sun's total irradiance, only about 1/4 of the laser light would be absorbed.
Thanks for the answer :)
Wouldn’t it be easier to have the laser mounted on the space station pointing to earth?
That would make the experiment infinite times harder. You'd have to design, transport and mount that laser on the ISS. All they need up there is a handheld camera in this experiment.
Von Bergerfurth I don't think so with today's computers and calculations a fixed point on earth would surely be easier to calculate than than trying to calculate exactly the small pinpoint of a fast moving tiny dot.
@@Problembeing that fixed point on earth would be just as hard to track from the ISS as it is to track the ISS from earth, and it would cost millions of dollars.
@@Problembeing you also have the problem of the light of the sun reflected by the ISS, you probably wouldn't see the laser anyway.
Von Bergerfurth that would be a problem firing the laser from Earth I’d suggest. Also, less of a problem at night.
Can I zoom radio satellite or television with telescope at higher orbits presumably it should stay static to where I zoom in since it orbits same direction earth rotates right?
the video of the space station passing over the sun is the coolest video I've seen all week
The astronauts experienced time travel, they saw 1.67 ms in the past😂😂😂
I always wondered this. Thank you!
I see "Numerical Recipes" on the bookshelf! I loved that book
Thank you Scott Manley your vids are pretty real.
If you illuminate a police helicopter around here, they have got very efficient at quickly finding out where the laser came from and send a patrol car out there.
I have a bright green laser that can mount on a rifle. If I point that at the space station will I get in trouble? I would be pointing a gun at people.
You are pointing a gun at people allthe time (through the earth when you are pointing it down), so probably not because this huge distance is basically an obstacle you can't overcome with a handheld gun. The bigger problem would be that bullets could hit people on the ground when they fall back down (don't know how dangerous this actually is).
Don't point guns at people.
Neat legal fact: In Germany, you could get in trouble if you assumed that you could shoot the ISS and actually tried to act on it; since even though your shot had no chance of hitting, it was based on a fundamentally valid theory of physics.
The reason for this distinction is to differentiate between genuine murder attempts and people trying to say, hex or curse or wish others to death, because even given intent the law does not acknowledge magic as a plausible mechanism of murder. (So-called "superstitious attempted murder". )
What, does the fundamental valid theory of physics not include ballistics in Germany?
It's an *inadequate* attempt, but it's not an *imaginary* attempt.
When a star party inadvertantly started an interstellar war. 😛
those guys with the boards accidentally sent a bad word about the orange haired Martian president's wife.
*The ISS wants to know your location*
Easy. Right there at the green dot on the ground.
I was present at that San Antonio Astronomy Association event and the blue laser was not robotically tracked but had a human operator on a mount to help it glide. There were no motors but was human powered.
Light is now being tested for broadband communications to/from space. Look at the "OPALS" project here on TH-cam.
Where has his launch abort tower gon on his Saturn v?
Light amplification by stimulated emission of radiation
Huh. So i guess atmospheric scattering doesnt affect it that much.
basogoreng not much no. Not for green anyway. Blue would be a different story but our atmosphere is actually pretty clear (why we can even see stars) scattering happens but blue experienced severe Rayleigh scattering with blue wavelengths (can’t remember the exact wavelengths ) which is why it appears blue during the day
I learned something designing X-Ray detection boards. For every doubling of the distance from the source, the energy of photons drops by 4.
Inverse square law
That's the 1/r^2 law, and every EM source in the universe obeys it.
Hi Scott, how can you send a distress signal using a laser pointer, if you are caught unfortunately in those situations like plane crash on mountains or after jumping out of the sinking boat?
Sos signal
simple yes or no would be fine
I agree !
It's refreshing to hear someone with a Scottish accent talking about something other than drinking and fighting.
Or football.
Nice Imperial Assault Carrier on the top shelf. It needs some TIE fighters in the docking pylons though. ;-)
Andrew Elliott That's what that is...
Pyrrhic Wins "that's what that is" what? TIE fighters attached to the pylon. It carries 4.
Andrew Elliott Hmm, I had been trying to find out what ship that was until I saw your comment.
Very informative, Scott. Thank you. I use a green laser pointer in my back yard with my telescopes. I live within a mile of a regional airport and simply don't use it when aircraft are around.
Did I miss you calculating the angle of trajectory for distance?
Nah I just used 500km which would account for ~40 seconds of station overflight if you were directly under it.
Right, thought so. When you went on to say about the ISS being in the dark and hitting it's location I thought to myself it would be unlikely to be directly over you. So 500, could change quite a bit, but how much?
You would know you succeeded when the cops show up
That's when you point the pointer at a friend and say they did it
A simple yes or no would have been sufficient
iss astronaut comfirmed
Something i often wondered, thank you Scott, i remember my kids having a little cheap red laser, i blew their minds with a 5Mw green laser which we could see on the high clouds in the night sky
Lies. There's no such thing as a 5,000,000 watt laser. Your kids would be dead from a laser with millions of watts of power.
ask the cops from Portland if they can see period... fuccn HELL some those are so strong
Thought this would he a yes or no answer... Fell asleep.