Oh great. Now we have lightning equipped with lasers.

By Phil Plait | September 6, 2011 6:20 am

Oh, when will scientists learn? First it was laser pointers, then sharks with lasers. Now? Lightning storms with lasers.

[Click to enteslanate.]

What could possibly go wrong? Dun dun DUNNNNNNNN.

OK, fine. In reality, this picture actually shows a storm approaching an observatory testing out a new type of laser guide star system; lasers can be used as a way of increasing the resolution of telescopes. The storm was still a ways off, but from the photographer’s view the laser was superposed over it, and happened to catch a pretty dramatic lightning bolt in the picture.

I was interested to read that the laser had a power of about 20 Watts. A decent green laser pointer has a power of roughly 1/5th of a Watt, so this one is 100 times as powerful. I’ve used a 1 Watt hand-held laser before, and it literally scared me; it was so bright it felt like a weapon. The laser seen above is a lot brighter yet, and they need to have spotters when they’re used to make sure no airplanes are nearby. The beam might (under extraordinary circumstances) damage the plane, and would surely blind the pilot; not a happy circumstance.

Of course, lightning is even more powerful. After this picture gets around, I expect SyFy will air "Megalaser versus Superlightning". Which I would totally watch.

Image credit: ESO/M. Kornmesser

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CATEGORIZED UNDER: Astronomy, Pretty pictures

Comments (48)

  1. John O'Meara

    I don’t care how good laser guidestar AO has gotten, it can’t see through clouds…. ūüėČ

  2. Alex

    You can now do Laser Guide Star AO with a 10 Watt (wimpy‚Ķ) UV laser. Those things actually don’t need spotters, and so can be totataly autonomous. Robot telescopes with lasers!

    Check out the Robo-AO project for an example of a laser wielding robot telescope.

  3. I could see the laser blinding a pilot, but I have trouble believing that it would be able to damage an airplane. It isn’t like the airplane is hovering over it so no single spot is going to get that hot, and the metal on the airplane will help quickly conduct heat away from any particular spot. This is why some airplanes can get away with using big parts magnesium; sure, if it heats up enough it will burn quickly, but heat would get dispersed too quickly. This should apply all the more so to aluminum and other metals used in modern airplanes.

    Am I missing something here?

  4. cerberus40

    A twenty watt laser wouldn’t harm an airplane; it wouldn’t even harm you (as long as you kept it away from your eyes), just heat you up a little.

    The ESOcast just released a vodcast on this laser‚Äíit’s Episode 34 at their archive.

  5. ” it literally scared me; it was so bright it felt like a weapon”

    An elegant weapon for a more civilized age, If I may add.

  6. chris j.

    what was the wattage of the laser you used to test the idea of deflecting comets on your show?

  7. Al Cibiades

    The order of magnitude (20W vs 25kW military) is significant: Higher energy can be sufficient to melt/burn and/or destroy remote objects moving at high speeds.
    Military application of 25kW to 100+kW laser systems can bring down aircraft at a range of miles.
    20 W would probably not be capable of airframe damage.

  8. Digital Atheist

    Enteslanate? Yay Nikola. I never thought he was gonna get that death-ray contraption to work, be here you give us proof that he did.

    Wait, whadda ya mean this ain’t his work? Observatory? Telescopes? What is this nonsense of which you speak?

    “As soon as completed, it will be possible for a business man in New York to dictate instructions, and have them instantly appear in type at his office in London or elsewhere. He will be able to call up, from his desk, and talk to any telephone subscriber on the globe, without any change whatever in the existing equipment. An inexpensive instrument, not bigger than a watch, will enable its bearer to hear anywhere, on sea or land, music or song, the speech of a political leader, the address of an eminent man of science, or the sermon of an eloquent clergyman, delivered in some other place, however distant. In the same manner any picture, character, drawing, or print can be transferred from one to another place. Millions of such instruments can be operated from but one plant of this kind.” Nikola Tesla, 1908.

  9. Dr.Sid

    Now that is a laser my cat would like ..

  10. Chris

    @Joshua Zelinsky
    I agree with you I don’t see how the laser could damage the plane, unless there are some optical sensors I don’t know about. A blinded pilot could do some damage. I’ve used 10 W lasers before and it takes quite a while for them to bore into a brick beam stop. It’d take even more time when dealing with a shiny outer covering of a plane. Also the laser beam diverges as it travels. It’s not the beam power that’s important, it’s the power density. W/cm^2. The laser beams cutting metal are focused to sub mm areas. I doubt an adaptive optics system is that focused.

    And if you think of it, if a laser beam was strong enough to burn a hole in a plane, it wouldn’t just blind the pilots, it’d burn their faces off!

  11. Dr J

    @Joshua: you are right, as it is launched from the telescope the laser is not powerful enough to damage an airplane (you can even stick your hand in it), but it could blind its pilot or passengers. Nevertheless, it’s the most powerful laser on any civil telescope on the planet. However, no airplane watchers are required because there is a no-fly zone in the area between 11:30pm and 5am. It is the pilots’ responsibility to stay away.

  12. Trebuchet

    Do they have to notify the FAA before firing that thing up? I’d hope so. A NOTAM (Notice To Airmen) is in order.

  13. Naked Bunny with a Whip

    That’s not an observatory. It’s one of Earth’s laser defense grid pods.

  14. Pete

    That reminds me of my favorite property of laser-based communications systems – if something’s blocking the signal, just bump up the power a few watts, repeat as needed.

  15. gdave

    @Joshua Zelinsky & @Chris:

    I don’t know what Phil was thinking of with that “damage the plane” comment, either. If a 20W laser were capable of damaging an aircraft that accidentally passed through it, we’d have an operational “Star Wars” missile defense system by now.

  16. Left_Wing_Fox

    How long before this shows up on conspiracy sites as a CIA laser-based lightning generator weapon used to kill dissidents? After all, a lightning strike took out the King of Kings statue (Aka: Big Butter Jesus) on I-75 last year, but not the porn store next door. Coincidence? Tell to the tinfoil, cause my brain’s not on your frequency, man!

  17. Dag

    WHOA! Awesome!!!!!

  18. Belgarath

    I’m going to concur with the other posters.

    I know that lasers can and have caused problems with pilots vision (the stories of eye damage seem a bit overboard) but I would need to have much more information on how this could damage a modern airliner.

    There are no optical sensors which could be burned out by this and the time of interaction would be very small, even at approach speeds.

    Consider, if you were to aim this such that a passing car could go through the beam at a distance of 1500 feet, doing 60mph. What would be damaged on the car? Now double the speed of the car and you’re close to an airplane passing through it.

    In any case, still it’s a cool picture.

  19. QuietDesperation

    The beam might damage the plane

    A maser might if it’s the right frequency to bork the plane’s electronics at some point, or maybe a high power radar focused to a pencil beam.

  20. No, the plane probably wouldn’t be damaged by the beam, but even if the pilot wasn’t permanently injured by the laser, “flash blindness,” a temporary condition can occur. For this reason, all outdoor laser operations into the atmosphere must be cleared by the FAA prior to propagation. Observatories with AO lasers are pretty familiar with this requirement.
    I’m more concerned that Phil uses a 200 mW green laser pointer! That’s a pretty high-powered Class 3B laser. Maybe check the label…it should be a Class 3R with less than 5 mW to be legal. However, there are plenty of laser pointers out there that aren’t…

  21. There have been a number of cases of pilots being temporarily blinded by lasers and thus left unable to fly the plane. Not sure if there was any permanent damage.
    Also, people have been arrested for pointing lasers at aircraft.
    Finally, when I was growing up on Dantooine, I used to routinely target womp rats with my laser and it would blow a hole clean through them. Don’t recall the wattage, though, as this was a long time ago in a galaxy far, far away.

  22. Gary B

    Point of reference – the book “Build Your Own Laser, Phaser, Ion Ray Gun and Other Working Space Age Projects” has instructions for a 20 watt CO2 infrared laser. Among other warnings, it points out that the writer accidentally walked through the beam, 30 feet away. It sliced open his jeans and caused a skin wound. So yes, a 20 watt laser is getting right up there into at least the ‘potential weapon’ level.

    Damage to a plane would certainly require more power due to the speed with which the plane would be transiting the beam. Also it would depend on the paint on the plane – paint would absorb the heat much better than shiny aluminum. But eye damage even a mile or two up seems quite possible.

  23. Nigel Oulton

    Phil I am amazed you missed out the most tech geekiest part about this new laser for the European Southern Observatory – it isn’t its power, which is impressive enough and imagine the fun you could have annoying your cat with it and the number of YouTube video’s. What is impressive is that it is going to take over from the previous laser guide star system used by ESO and it replaces a whole room full of hardware plus staff to keep it running optimally that made the existing system work, but the new laser is about the size of a cake tin mounted on the telescope and apparently is self contained requiring just scheduled maintenance – oh and they are going to use 4 at the same time to make their results even more accurate than previous.

  24. Douglas Troy

    Dr. Plait … if we were to fire the EMDL (Earth Missle Defense Laser) into the storm, the SDNP (Storm Disruptor Nano Particles) could use the laser to travel into the storm wall and absorb all the energy and save the city! It just … might … work …

  25. TGAP Dad

    Actually, Phil, I believe consumer laser pointers are limited to 5mw output, and need an IR filter on them. 1/5th watt (200mw) is plenty strong enough to cause eye damage and minor burns.

  26. Clearly this is a photo of an *incoming* laser hitting our defensive shields. The so-called lightning is the energy being dispersed.

  27. Chris

    Will it damage a plane? Sounds like a job for Mythbusters!

  28. Marcum (20) and others: my standard-issue green laser pointer has a label that says the max power is “<160 mW", though it does not say what the actual average power in the beam is. But that's about 1/6th of a Watt, so I used that as a reference.

    My point about damaging the aircraft was from the idea that when I used a 1 Watt laser, I could pop balloons and burn paper within a fraction of a second. A beam 20 times that power would be more damaging. I wasn't thinking of a plane passing through the beam so much as the beam being held in one place, so I can see what I wrote is misleading. I added some weasel words to amend that. :)

  29. Mike H

    20 watts? Are we sure it’s not 1.21 gigawatts?

  30. Joseph G

    Dumb off-topic question here, but what’s the difference between “superposed” and “superimposed”? ‘Cuz I would have used the latter word, but then, I’m not an astronomer (or a photographer), and I’m sure I’d have been wrong.

    Also, this picture definitely earns a running in the “Most Badass Photo of the Year” award. All that’s missing is Chuck Norris jump-kicking a machine gun-toting bear.

  31. Chris

    @ Phil Plait
    I certainly hope the skin of a plane is stronger than a balloon or a piece of paper, unless it’s a paper airplane. It might be interesting to see if a laser could pop a hot air balloon.

  32. doug baker

    I would enjoy this picture as a poster. Who owns the copyright?

  33. doug baker

    sorry about that, still have trouble with my mobile device.

    I would enjoy this picture as a poster, Who owns the copyright?

  34. Chris Knight

    Ha! You haven’t lived until you’ve popped a ball of popcorn twenty feet in diameter with a five megawatt laser mounted on a B-1.

  35. Blake

    Well, I think Dr. Plait has received more than ample rebuke for the plane damage comment (it’s nearly inconceivable that a mere 20W laser could physically damage a plane at a distance), but I will go a step further and say that there isn’t even any appreciable eyesight risk to pilots from these laser guide stars.

    Let’s take a 20W (this seems to be a typical power for such things) laser guide star operating at the sodium doublet wavelength of ~589 nm (the yellow color you see in street lamps) as an example. Usually the laser is launched not in a pencil-lead thin beam as you see from a laser pointer, but from a telescope of several tens of cm aperture, let’s use 30 cm as an example. Now, the beam area of such a laser is going to be ~700 cm^2, giving the intensity at any one point inside the beam of a mere 29 milliwatts per square cm. Add to this fact that a dark-adapted, dilated pupil has an aperture area of only half a cm (~8mm dia), and neglecting path losses which it must be said are likely non-trivial, the absolute maximum amount of power that can reach the retina is now down to 15 milliwatts. Three times the power output of a typical 5 milliwatt laser pointer.

    Add to all of this that laser guide stars are fixed to point at one spot on the sky (sky motion is trivial and can surely be neglected) and the speed of the plane must be at least, say 100 mph (4,500 cm/s), and the pilot in a plane unfortunate enough to fly through the beam while staring directly into it will have a maximum retinal exposure time of a whopping 7 milliseconds!

    The amount of energy that can be deposited on a person’s retina in that amount of time at that power level, is simply trivial. At most, the pilot will experience a quick flash blindness of the kind you get after seeing a camera flash go off and the effects will almost certainly fade within a very short period of time. Beams of this intensity, used for this purpose, are complete non-hazards for both plane structural integrity and pilot eyesight.

    However, I’m not sure if Phil is aware of it, but there ARE LASERS that are used to trigger lightning (with varying levels of success) which were recently in the news. These lasers are MOST DEFINITELY NOT eye safe by any means, being pulsed lasers in the TRILLIONS of watts range sufficient to ionize air.

  36. Joseph G

    You think Phil’s laser pointer is dangerous – there’s a laser pointer site I just found selling a 1300mW laser pointer that they boast can light cigarettes.

    The scary thing is, that same page where you can purchase this thing has absolutely no warnings on it (other then “laser stings bare skin,” which is up there with features rather then a warning).
    It’s clearly marketed as a laser pointer (“for teachers, doctors, professors, etc”) that is “easier then pointing with your hands”. Oh, there’s also a close- up of the laser with a caption “laser comes out here”. I s**t you not.

    I think I’m going to get some laser-protective goggles and wear them in public all the time, just in case.

  37. Dr J

    @Phil and others: Regarding the potential damage this laser could do it seems to me that you are missing an important point: It’s not so much the *total* power of the laser that counts but the energy *density*. The laser in the picture is launched by a ~30 cm telescope and so the laser’s energy is distributed across a 30cm wide beam. That’s why it’s not dangerous. Like I said above, you can stick your hand in it – I know, cos I did. If the same laser is concentrated into a much narrower beam of, say, a couple of mm across (as in a laser pointer) then this would be a very dangerous device.

  38. Wzrd1

    @35, Dr J, I don’t know. If one held the beam a lens for one of the aircraft beacon lights for a few seconds, it might deform a bit. :)
    Of course, you’d also be slewing the telescope and ludicrous and destructive speeds.
    It’d probably make it to plaid…

  39. Blake

    I would also like to amend the comments of Dr. J above, and say that if you’re still worried about 20 watt laser guide stars, consider the average light show at you local concert. Beam irradiance, and not merely total power, is everything. Typically these shows use bright green doubled YAG lasers at 532nm emitting sometimes more than 50 watts in a thin, few-mm diameter beam. Now, the divergence of a beam like this is considerable, as the emission apertures are very small, but they present at least as much of a hazard to pilots as LGSs. There are reports of pilot eye injuries from these kinds of shows which are of varying but usually mild, temporary severity.

    And this is to say nothing of the fact that some light show presenters SCAN THE CROWD with multi-tens of watt beams of this sort, such as here: http://www.youtube.com/watch?v=Qus9rv2V2fg

    The eye injury reports from concertgoers at these sorts of events are somehow shockingly rare, given the number of people exposed every year. Still, I absolutely do not trust my eyes to some nobody who runs light shows on the weekends for spare change, and would leave any establishment where audience scanning was occurring without a second thought. IMMEDIATELY.

  40. How long before we see a headline “Secret government program creates lighting with lasers”. I bet they will attribute it to china. Tell Snopes to be ready.

  41. How long before we see a headline “Secret government program creates lighting with lasers”. I bet they will attribute it to china. Tell Snopes to be ready.

  42. lythander

    Seriously, spend a bit of time googling LIPC (laser-induced plasma channel) weapons. Very scary. Also, read DAEMON by Daniel Suarez, where these weapons make an appearance.

  43. MadSciKat =^..^=

    “Megalaser versus Superlightning” w00000000+! Checking TVGuide listings now‚Ķ

  44. mike burkhart

    These are two diferent types of energy:the laser is light energy the lightning is electricity .Now the laws of Physics say that energy can be changed from one form to another ,but not like this. You could use a laser to heat water and use the steem to power an generator that turns light energy to heat energy to electricity.

  45. Rachel D.

    ESOCast had a great little video detailing the laser system. Dr. J isn’t as awesome as Dr. Plait though….but I may be a tad biased in my opinion….

  46. Nigel Depledge

    Mike Burkhart (44) said:

    These are two diferent types of energy:the laser is light energy the lightning is electricity .Now the laws of Physics say that energy can be changed from one form to another ,but not like this. You could use a laser to heat water and use the steem to power an generator that turns light energy to heat energy to electricity.

    Well, this is right, as far as it goes, but if you go a bit more fundamentally, light and electricity are both phenomena of the electromagnetic force.

    A sufficiently powerful laser will ionise the air through which it passes, creating a line of plasma (well, strictly speaking it’s only a plasma if all the electrons are stripped off the atoms, but air only needs a few electrons to be knocked loose to suddenly become a much better conductor). If the clouds have built up some electrical charge (as happens in thunderstorms), then the laser will indeed trigger lightning, as the charge in the cloud suddenly encounters a low-resistance path to Earth.

  47. Nigel Depledge

    Oh, yeah and:

    Wow! That pic is so freakin’ cool!

  48. JMW

    One of my favourite product warning messages, in the user manual for a laser pointer:

    Do not point laser at remaining eye.


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