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An Interplanetary Laser Communications System

timothy posted more than 9 years ago | from the sharks-not-included dept.

Communications 303

caffiend666 writes "A news article at Yahoo states NASA is planning on testing the first laser-based interplanetary communications system on the Mars Telecommunications Orbiter to be launched in 2009. 'Unlike radio frequency signals that wash over the entire Earth, Fitzgerald and his colleagues will be shooting for a much smaller target - the southwestern corner of the United States.' Does this mean we will soon have telescopes outside of our homes soon to pick up high definition TV signals instead of our current 18 inch dishes?"

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GNAA FP (-1, Offtopic)

Anonymous Coward | more than 9 years ago | (#10827250)

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It's eventual use. (5, Funny)

teiresias (101481) | more than 9 years ago | (#10827251)

Earth - 'Hey'
Mars - 'Hey'
Earth - ...'
Mars - '...'
Earth - 'a/s/l?' ;)

Re:It's eventual use. (1)

addaon (41825) | more than 9 years ago | (#10827390)

4000000000/i am multitudes/duh

first is of the you (-1, Offtopic)

Anonymous Coward | more than 9 years ago | (#10827252)

i am the first, you suck

Not Really (-1, Troll)

mfh (56) | more than 9 years ago | (#10827255)

Does this mean we will soon have telescopes outside of our homes soon to pick up high definition TV signals instead of our current 18 inch dishes?

No, it means the southwestern corner of the USA is going to become the Intarweb capitol of the universe!!!

tehe (-1, Troll)

Anonymous Coward | more than 9 years ago | (#10827257)

i wonder how easy it will be to pirate!

Re:harder than your mom (-1, Troll)

Anonymous Coward | more than 9 years ago | (#10827273)

probably not as easy as your mom was...

FORST LASER (-1, Troll)

Anonymous Coward | more than 9 years ago | (#10827259)

Watch out planets !

First Post (-1, Offtopic)

Anonymous Coward | more than 9 years ago | (#10827260)

All Your Base Are Belong To Mars

Time to do the wash (5, Insightful)

kfg (145172) | more than 9 years ago | (#10827261)

Does this mean we will soon have telescopes outside of our homes soon to pick up high definition TV signals instead of our current 18 inch dishes?"

No.

Because for television broadcast to the general population you want to wash the signal over the whole earth, rather than trying to target each receiver. And if you think your reception sucks when it's raining out now. . .

KFG

Re:Time to do the wash (1)

SetupWeasel (54062) | more than 9 years ago | (#10827337)

A dish is a telescope. Ever see a picture of Aricebo?

Check it! [naic.edu] Just a big version of what you got on your house.

Re:Time to do the wash (1)

strict3 (827367) | more than 9 years ago | (#10827364)

A dish is a telescope.

No, that is a radio telescope, which is just a big radio antenna.

Regular telescopes use optics. Dishes use none.

Re:Time to do the wash (1)

SetupWeasel (54062) | more than 9 years ago | (#10827396)

The dish is a mirror. It's purpose is to collect EMR over a large area, and focus it into a single point. It is a basic reflective telescope for radio waves.

Re:Time to do the wash (2, Funny)

kfg (145172) | more than 9 years ago | (#10827414)

Ever see a picture of Aricebo?

Yes. I've even taken pictures with radio telescopes, although not of the Aricebo facility. I've got an invisible light laser hanging around the place in some drawer or other too.

I've never been to Aricebo myself, but my mother has. She took pictures of it, in visible light.

Just a big version of what you got on your house.

My house is not so bedecked.

KFG

Secure Communication and the Chinese Threat (-1, Troll)

Anonymous Coward | more than 9 years ago | (#10827352)

What is interesting about this laser technology is that it enhances secure communication. You can point the laser at precisely the location which should be receiving the encoded signal.

As usual, we must ensure that this technology remains in the West. China remains an ever present threat [tibet.org] to peace and stability. This technology would enhance China's ability to wage war against Western society.

Re:Time to do the wash (0, Redundant)

mfh (56) | more than 9 years ago | (#10827357)

You know, I said the same exact thing and was modded to -1 for doing so. This is interplanetary folks. The best way to get signals around earth now is through our own planetary/local signals or through wire/fiber. Going between planets, we'll be able to have one major feed or more, and the signals going through that system will feed to local systems using whatever works best at the time. The beauty of this is that there won't be the lengthy delays between messages, and continual improvements will make the range increase for larger file transfers or whatever.

Huh? (3, Informative)

Bill, Shooter of Bul (629286) | more than 9 years ago | (#10827388)

What does that have to do with anything? Going between planets we will still be limited to sending messanges at the speed of light. aprox 16 minutes from here to mars. There most definitely *will* be a lengthy delay between messages.

Re:Huh? (0, Flamebait)

mfh (56) | more than 9 years ago | (#10827450)

There most definitely *will* be a lengthy delay between messages.

Don't you watch Star Trek? (Am I still posting at /. or what??? uhm... maybe I'm reading the Kuro5hin tab in firefox, then... nope... it's /. alright. Welcome, sir!)

Re:Time to do the wash (-1, Offtopic)

Anonymous Coward | more than 9 years ago | (#10827421)

You know, I said the same exact thing and was modded to -1 for doing so.

Actually, you just said no without even an attempt to explain why, and made some silly joke that I still don't get.

56?

Re:Time to do the wash (1)

Derling Whirvish (636322) | more than 9 years ago | (#10827400)

Because for television broadcast to the general population you want to wash the signal over the whole earth, rather than trying to target each receiver.

Unless you are something like the license-fee-funded BBC where you want only British television-license-payers to receive your signal and not any Germans, French, or anybody else.

Re:Time to do the wash (1)

kfg (145172) | more than 9 years ago | (#10827428)

Then I can't say I'd recommend broadcasting from Mars in the first place.

KFG

Dishes ARE Telescopes! (5, Interesting)

CyberBill (526285) | more than 9 years ago | (#10827267)

I always wondered why they would want to use the visible spectrum...

We *CAN* make Laser-Radio waves! They go through atmosphere and trees and buildings....

Re:Dishes ARE Telescopes! (1)

uberdave (526529) | more than 9 years ago | (#10827288)

The L in LASER stands for Light. Perhaps they could use MASERs.

Re:Dishes ARE Telescopes! (4, Informative)

Anubis350 (772791) | more than 9 years ago | (#10827315)

light is not restricted to the visible light we can see. radio waves are a form of light. so is infared. gamm radiation, microwaves, etc.

Re:Dishes ARE Telescopes! (1)

kfg (145172) | more than 9 years ago | (#10827328)

radio waves are a form of light.

Ah, but then why do they even bother calling masers masers, Mr. Smartypants?

KFG

Re:Dishes ARE Telescopes! (1)

Anubis350 (772791) | more than 9 years ago | (#10827341)

to be more specific: from a googled definition [bandwidthmarket.com]

maser: Acronym for microwave amplification by stimulated emission of radiation. A member of the general class of microwave oscillators based on molecular interaction with electromagnetic radiation.

Re:Dishes ARE Telescopes! (2, Informative)

uberdave (526529) | more than 9 years ago | (#10827342)

And supplementarily, lasers were originally called optical masers.

obligatory austin powers misquote (4, Funny)

Anubis350 (772791) | more than 9 years ago | (#10827270)

will this be implemented with sharks with frikin lasers on their heads?

MOD UP -- HILARIOUS! (-1, Troll)

Anonymous Coward | more than 9 years ago | (#10827324)

I simply can't get enough of that Austin Powers quote!!! Can someone please post a message about welcoming our new laser-powered Mars overlords, too? That's my second favorite slashdot posting. And then someone else please post something about how the server seems to have been vaporized by lasers due to the slashdot effect! I'll be rolling in my chair with laughter! Mods, please mod all this stuff up!!!

Re:MOD UP -- HILARIOUS! (-1, Offtopic)

Anonymous Coward | more than 9 years ago | (#10827333)

your lack of faith disturbs me.....

Re:MOD UP -- HILARIOUS! (-1, Offtopic)

Anonymous Coward | more than 9 years ago | (#10827353)

In Soviet Russia, lasers communicate with YOU!

Re:obligatory austin powers misquote (0)

Anonymous Coward | more than 9 years ago | (#10827382)

Yes, they'll (DARPA) probably install it on the brand new remote controlled sharks.

See: Captain America:Superhero of the Military-Industrial Complex [commondreams.org]

Re:obligatory austin powers misquote (0)

Anonymous Coward | more than 9 years ago | (#10827394)

You're a retard. The quote is.

Sharks with frickin' laser beams on their heads?

Watch the movie again 'tard.

Re:obligatory austin powers misquote (0)

Anonymous Coward | more than 9 years ago | (#10827399)

obligatory austin powers misquote

Re:obligatory austin powers misquote (1)

OneArmedMan (606657) | more than 9 years ago | (#10827410)

I shall call it a "finger quotes" Death Star "finger qoutes"

*cough cough* Rip off ....

In Soviet Russia (-1)

Anonymous Coward | more than 9 years ago | (#10827424)

In Soviet Russia Frickin' Laser headed Shark beams YOU!!!

Very specific uses (5, Interesting)

Chairboy (88841) | more than 9 years ago | (#10827272)

It's unlikely you'd use lasers for wide scale signal distribution. A laser must be aimed, and to provide a signal to a thousand receivers you would need to fire a thousand beams, or have some intricate device that actively retargets thousands of times per second, squirting packets off to each receiver. Moving parts, complicated, no clear advantage.

Lasers for interplanetary communication is another thing. It's one sender to one receiver, and then you can go radio for inside planetary systems. Eg, you could set up a Mars Relay Station that takes low power local radio transmissions and beams the info back to Earth via laser, and vice versa. You get the advantage of cheap, small radio technology plus the range and bandwidth of laser.

Re:Very specific uses (-1, Redundant)

Anonymous Coward | more than 9 years ago | (#10827412)

This will help with dispersion and the attenuation of radio coms, but at ranges where it is a problem, travel time is already a major factor. And then there is the extra difficulty of doing relativistic calculations in order to aim this communications laser correctly. I found another article on the subject, dealing with relativistic communications, over at How Stuff Works [howstuffworks.com] .

Re:Very specific uses (4, Interesting)

Naikrovek (667) | more than 9 years ago | (#10827510)

when i was a kid (early 80s) my dad set up a thing kinda like that. he used a focusable flashlight, hooked it up to an amplifier, and pointed at a sensor he had in the window of our detached garage.

whenever he'd go out there to work, he'd turn on a microphone in the house, and turn the reciever in the garage on. he originally built it when cordless phones were a high-priced luxury, and didn't want to wire a phone just for the garage, but he still wanted to hear the phone ring from in there. later he used it to listen to the TV while he worked outside.

he used a cadmium-sulfide cell on the recieving end. those change resistance according to light. conveniently, they ignore the signal bias (ambient light) and only respond to changes in light intensity. the amplifier inside the house changed the amount of current to the flashlight, and thus the brightness. that variable-intensity light got sent to the CdS cell and the variation in light was reproduced into sound. it sounded surprisingly clear. i don't remember a muffled sound at all.

you could update the design by using polarized light going in two directions. horizontal polarization for transmission, vertical for reception, or simply seperate them a little. our seperated garage had a window adjacent to our home, and light shined into the garage would bounce off the glass and back into the house. if we tried to do two-way then we would have had some signals bouncing off windows in weird ways, and probably some weird sound->light->sound->light feedback loop.

wonder what that would have sounded like...

anyway the setup worked great, and my dad used it until the day he died. good designs last.

I recently tried it again with a laser pointer, but it seems that they have voltage regulators in them that smooth out the variations far too much.

That's going to make for... (4, Funny)

Brad1138 (590148) | more than 9 years ago | (#10827275)

Some serious lag in UT2004

Re:That's going to make for... (1)

Anubis350 (772791) | more than 9 years ago | (#10827285)

from the article
For scientists eager to download bandwidth-intensive imagery and other data collected by planetary orbiters, probes and landers, the laser communications would offer a dramatic breakthrough in the amounts of information spacecraft can reliably transmit back to Earth.
itd be faster tdio signal.....
not sure, doesnt give nums, but it might be faster than 56k....

Re:That's going to make for... (1)

Anubis350 (772791) | more than 9 years ago | (#10827297)

woops, yes it does
NASA's Mars Odyssey orbiter, in contrast, transmits data at about 128,000 bits per second, or about twice as fast as a dial-up connection but a tenth the speed of the typical broadband Internet connection
I guess I was right....

Re:That's going to make for... (0)

Anonymous Coward | more than 9 years ago | (#10827338)

Bandwidth != Latency

Re:That's going to make for... (1)

Anubis350 (772791) | more than 9 years ago | (#10827350)

point taken, perhaps turn based multi-player games would be better....

Re:That's going to make for... (1)

dadjaka (827325) | more than 9 years ago | (#10827308)

Yes, especially considering that with the orbit we're on, any one part of the earth is not always going to have line of sight to Mars.

The delays could make the 40 min radio round trip look fast!

Obligatory shark reference (0, Redundant)

ExtremeGoatse! (778447) | more than 9 years ago | (#10827279)

So now we'll finally be able to send signals to those sharks with friggin laser beams on their heads.

4.3 Gigabytes (4, Interesting)

morcheeba (260908) | more than 9 years ago | (#10827283)

a little math...

344 million km / (0.3 million km/sec) = 1147 seconds travel time
1147 seconds * 30 megabits/sec peak rate = 4.3 Gigabytes in transit at any instant.

Re:4.3 Gigabytes (1)

ArbitraryConstant (763964) | more than 9 years ago | (#10827330)

Almost like mercury delay memory. :)

Re:4.3 Gigabytes (1)

jfengel (409917) | more than 9 years ago | (#10827398)

That's it! Instead of a hard disk I'll just put a reflector on Mars. (Too bad it's only available a few hours a day.)

I guess 4.3 gigs isn't a big hard disk any more. Better build one on Saturn instead.

Re:4.3 Gigabytes (5, Funny)

gnuman99 (746007) | more than 9 years ago | (#10827422)

That's it! Instead of a hard disk I'll just put a reflector on Mars.

Your seek time will be astronomical!

Re:4.3 Gigabytes (-1, Troll)

Anonymous Coward | more than 9 years ago | (#10827373)

a little math...

344 million km / (0.3 million km/sec) = 1147 seconds travel time
1147 seconds * 30 megabits/sec peak rate =
You'll still never get laid.

Re:4.3 Gigabytes (1, Redundant)

The Unabageler (669502) | more than 9 years ago | (#10827430)

so for pluto,

5913 km / 0.3 km/s = 19710 s
19710s * 30mbit/s = 591.3 TB in transit. How about a raid of laser planet storage devices? And then give them full boxen and make a beowulf....sorry I had to add that last bit.

Re:4.3 Gigabytes (1)

Bastian (66383) | more than 9 years ago | (#10827481)

You may laugh, but I knew a guy who was convinced that the future of mass storage was networks. The idea was exactly that - instead of putting stuff on a hard drive, send it to a computer across the network. That computer would just bounce the data back when it got it. When you needed info, you would just wait for the data to come back, then grab it.

The magic of all of this is you are using in-flight packets as storage!

OK, no, I don't get it, either.

Re:4.3 Gigabytes (1)

gingerTabs (532664) | more than 9 years ago | (#10827500)

1147 seconds * 30 megabits/sec peak rate = 4.3 Gigabytes in transit at any instant
But how does that compare to a shuttle full of DVDs for a comms link?

FTL commo the next step? (-1, Redundant)

Anonymous Coward | more than 9 years ago | (#10827290)

This will help with dispersion and the attenuation of radio coms, but at ranges where it is a problem, travel time is already a major factor. And then there is the extra difficulty of doing relativistic calculations in order to aim this communications laser correctly. I found another article on the subject, dealing with relativistic communications, over at How Stuff Works [slashdot.org] .

Radio is Light! *gasp* (4, Informative)

Dancin_Santa (265275) | more than 9 years ago | (#10827293)

Radio, or electromagnetic radiation, is a fancy name for a special spectrum of invisible light. Yes, Virginia, your radio is replaying music broadcast over light!

Also, a laser is a special form of coherent light. It just means that all the wavelengths in the beam of light are the same wavelength. It also means that the beam of light doesn't disperse very much unlike incoherent light (which no one can make heads or tails of what it is trying to say).

Since the radio requires a specific band to tune in to, it makes sense that the broadcasting station not waste time generating unnecessary wavelengths and focus on only those wavelengths that correspond to our chosen band. This restricts us to AM (amplitude modulation) bands only, but since we're trying to get data signals and not Martian stereo there is no big loss.

So why deal with visible light lasers when it could be invisible and work just as well?

Re:Radio is Light! *gasp* (4, Informative)

uberdave (526529) | more than 9 years ago | (#10827371)

All light is electromagnetic radiation, but not all electromagnetic radiation is light. Light is the small, visible portion of the elecromagnetic spectrum. So, Virginia's radio is *not* replaying music broadcast over light.

Re:Radio is Light! *gasp* (0)

Anonymous Coward | more than 9 years ago | (#10827389)

That's pretty arbitrary. Where do you set the cutoff? Some animals can see into the infrared range, some reach into the ultraviolet range. Blind people can't see any light at all. So what do you say is visible?

Re:Radio is Light! *gasp* (1)

dfn5 (524972) | more than 9 years ago | (#10827455)

So what do you say is visible?

Photonic forms of energy. Radio is not photonic, therefore is not visible. You can't shine a beam of light across a stretch of wire and get a current. They are different.

Re:Radio is Light! *gasp* (1)

Vellmont (569020) | more than 9 years ago | (#10827520)


Photonic forms of energy. Radio is not photonic, therefore is not visible.


Nope, all electromagnetic radiation is transmitted via photons. Photons just mean that energy is transmitted in discreet packets, and not continuously.

Re:Radio is Light! *gasp* (1)

uberdave (526529) | more than 9 years ago | (#10827472)

Talk to the FCC. They're the ones that divvy up the spectrum.

If we are just now experimenting with this..... (3, Insightful)

Conspiracy_Of_Doves (236787) | more than 9 years ago | (#10827298)

Does that mean that something like this might be in widespread use in advanced alien civilizations, and SETI has no chance of ever finding anything?

Re:If we are just now experimenting with this..... (5, Informative)

TheDayOfMe (808363) | more than 9 years ago | (#10827360)

That is why some are looking for lasers [harvard.edu]

Re:If we are just now experimenting with this..... (1)

iammaxus (683241) | more than 9 years ago | (#10827361)

Actually, we should be hoping that this is in widespread use with alien civilizations. This directed radiation leaks a lot less out of the solar system then relatively unfocused radio waves do. It has been speculated that we may not find advanced civilizations precisely because of reasons like this. There is no good reason to be just blasting radiation all over the place if you don't need to.

Re:If we are just now experimenting with this..... (0)

Anonymous Coward | more than 9 years ago | (#10827466)

Actually its highly likely that they're using some form of FTL Communication. One place for primitive earth scientists to look is EM radiation which travels faster than light, which does exist, but that has a different method of propagation.

This should have been realized decades ago (Tesla did talk about it and was ignored for his troubles) but the blind acceptance of Einstein's theories and fear of examing the anomalies in experiments meant to test his Theories of Relativity have obscured the ability of physicists to make any progress in FTL technology.

Probably not telescopes (3, Insightful)

reality-bytes (119275) | more than 9 years ago | (#10827301)

"... Does this mean we will soon have telescopes outside of our homes soon to pick up high definition TV signals instead of our current 18 inch dishes?"


Its unlikely because Optical Telescopes rely on somewhat precise pieces of equipment such as lenses which are not known for their 'year-round' hardiness.

Speaking from experience, line-of-sight laser communications systems can be a right-royal pain to keep maintained when they are within meters.

I don't know for sure, but I would image that initial targetting of your telescope would be a very tricky operation (and you know that sat dishes are hard enough). And then, once installed, the fixings would need to be exceptionally heavy-duty to hold the telescope on target during gales etc.

High frequency EMR? (2, Informative)

AlphaWolf_HK (692722) | more than 9 years ago | (#10827306)

AFAIK the higher frequency electromagnetic radiation you use, the more susceptable the signal is to physical interference (although the energy "particles" dissipate less so that it can have a more reliable signal over further distances.) I somehow doubt we would ever see HDTV coming in via telescope, unless of course you can find a cure for bad weather.

I only recently started taking chemistry courses though, somebody correct me if I am wrong.

Re:High frequency EMR? (1)

squidinkcalligraphy (558677) | more than 9 years ago | (#10827526)

Then how to you explain that both radio waves (low frequency) and x-rays/gamma rays (high frequency) can pass through most solids but visible light cannot?

Maybe the high energy of high frequency waves can just ram them through most things?

Typical (5, Insightful)

Anonymous Coward | more than 9 years ago | (#10827307)

Here's a story about an ambitious plan to build a laser-based interplanetary communications network and the only thing the story submitter is concerned with is how this will influence his TV reception.

This, my friends, is why the human race is doomed. Here on slashdot, where we care more about science than most people, all some people can think about is how a new technological advancement can facilitate the transmission of market-research-constructed-SitComs or advertisements for the latest yuppie gizmo to their home.

submitter was being a smartass, but they're right (3, Informative)

ArbitraryConstant (763964) | more than 9 years ago | (#10827309)

One of the limitations for geosynchronous satelites is that their proximity to each other is limited due to the unavoidable spread of the signal. Shorter wavelength means a tighter signal, which means more satelites.

Of course... cloud cover is a problem, but there are ways around that (like those robot blimps that loiter in a given area above the clouds).

LOL!!!!!! (1, Funny)

Anonymous Coward | more than 9 years ago | (#10827312)

"Does this mean we will soon have telescopes outside of our homes soon to pick up high definition TV signals instead of our current 18 inch dishes?"

Yes!!!! I get it!!! This is a joke in English!!!! Ha ha ha ha ha!!!!!!!! I am laughing at the joke!!!!!!!!!!!!!!!!!!

This is a good day friends!!!!!!! Let as laugh together like old comrades!!!!! :D :D :D :D

That's really cool, but....why? (3, Insightful)

Zen Punk (785385) | more than 9 years ago | (#10827323)

Perhaps I need to read TFA more closely, but I am left wondering what the advantages of using lasers for interplanetary communications would have over our traditional RF or microwave systems. After all, it's all EM radiation, so it's speed of light, and the lasers they're using apparently can't reach through clouds, so what are the reasons why you would want to use lasers instead of radio antennas?

BECAUSE LASERS ARE FUCKING COOL (1, Interesting)

Anonymous Coward | more than 9 years ago | (#10827331)

You idiot.

WTF? (0)

Anonymous Coward | more than 9 years ago | (#10827336)

Perhaps I need to read TFA more closely, but I am left wondering what the advantages of using lasers for interplanetary communications would have over our traditional RF or microwave systems.

Dude, because it's being done with lasers! That's reason enough.

Ask another question like that and we'll revoke your slashdot membership. You have been warned.

Re:That's really cool, but....why? (1)

DarkTempes (822722) | more than 9 years ago | (#10827413)

I don't understand how, but the article does point out why. The whole reason is that apparently using lasers instead of radio allows for more data to be transfered per a second (not necessarily 'faster' transfer since yes it is all the speed of light) and their estimates for th elaser speed (1mbit worst to 30mbit best) are far greater than the 128kbit that their current radio technology does...

Re:That's really cool, but....why? (0)

Anonymous Coward | more than 9 years ago | (#10827426)

Not to mention that lasers are the REAL ULTIMATE POWER! Lasers are so awesome! Sometimes just flip out and start zapping people for no reason at all! They'll just blow someone away and won't even think twice about it!

Re:That's really cool, but....why? (1)

uberdave (526529) | more than 9 years ago | (#10827449)

From another "Fancy Article" on the mission:

That leap in capacity is due to the different wavelengths of light carrying the data. The laser will use infrared light with a wavelength of 1.06 microns, which is thousands of times shorter than radio waves. Since all light travels at the same speed through space, shorter wavelengths carry more information in the same time.

Re:That's really cool, but....why? (4, Interesting)

jfengel (409917) | more than 9 years ago | (#10827467)

The advantage is that lasers are collimated, which means that the light doesn't spread out in a cone. Since you're concentrating the energy on a few hundred square miles rather than a few million square miles, you can broadcast with a lot less power. You can also make much more reliable communications, which means your bandwidth is higher.

In theory you can do this with any wavelength of light; if you do it with microwaves it's called a maser rather than a laser. Higher frequencies mean more bits, which is a good reason to choose light over microwaves, but the light is absorbed by clouds. I'm not sure about microwave frequencies, and I'm not sure if anybody's ever built a laser-type thing for radio frequencies (raser? I find people joking about it on the Internet but it doesn't seem unreasonable to me).

Eventually you might want a relay system: Mars to earth-orbiting satellite via laser, which then amplifies it and relays it to the earth on a frequency which cuts through coulds better, or just saves it up for a time when it can get through. But the first step is to see if you can get light accurately aimed at the Earth.

Re:That's really cool, but....why? (1)

Zen Punk (785385) | more than 9 years ago | (#10827479)

Thanks. I hope someone mods you up, I thought "LASERS ARE TEH AWESOME YOU DUMMY" was the best response I was going to get.

Re:That's really cool, but....why? (0)

Anonymous Coward | more than 9 years ago | (#10827488)

Because with radio waves, it's somewhat difficult to create a tight beam. The wider the beam, the more energy you need so that after the energy has dispersed at such massive distances you have enough to reconstruct your signal. Lasers are nice because you can form very tight beams and once you're on target, you get a crapload of bandwidth. NASA is interested in these for very long distance communcations and the military wants this because it offers extremely high speed, very jam resistant comm links. And atleast the military doesn't have a huge problem with clouds, they've already tested stuff that works through clouds.

To give you an idea of why this is so important... When you're way out around say Jupiter, you can really only communicate around a few bytes per second. I believe some of the extreme deep space probes operate around a couple BITS per second using essentially state of the art gear. With laser comm tech, you'd be dealing with megabytes per second. Slow by broadband standards but a quantum leap in terms of long distance communcations. And military comms are rather primitive too, the stuff they're launching in a year will give them a couple hundred T1 speed lines and a few thousand low speed (something like 2400baud if memory serves) lines. That would change to a LOT of mobile extremely high data rate (Gb/s) which would be able to service mobile terminals via some extremely sweet high speed pointing technology with all sorts of very awesome stuff like space based radar images.

In order, radio sucks compared to laser comm which is why laser comm is THE FUTURE of basicly all the new milsatcom initiatives like Tacsat.

Women (4, Funny)

3770 (560838) | more than 9 years ago | (#10827335)

I'd be happy if I could communicate with women. Why don't they work on that first?

Re:Women (1)

TheDayOfMe (808363) | more than 9 years ago | (#10827381)

With luck the Martian females are easier to talk to :)

Re:Women (0)

Anonymous Coward | more than 9 years ago | (#10827407)

That's more a problem of cracking the encryption instead of broadcasting. You typically don't want to broadcast your pathetic "Yes Dear" whimperings, anyhow. Or your accepting blame for all sorts of random things just so you can get sex that night.

Re:Women (0)

Anonymous Coward | more than 9 years ago | (#10827417)

Not only that, but communication between women is the fastest, most efficient thing known to exist. Tell one of 'em something and before you realize it, they all know.

Re:Women (1)

GreyWolf3000 (468618) | more than 9 years ago | (#10827433)

Now I know where BitTorrent came from.

Re:Women (0)

Anonymous Coward | more than 9 years ago | (#10827448)

You're never going to get ACK without SYN.

Grow some balls, talk confidently and honestly to as many femmes as you can. You'll find that not only do they speak the same language, but they sometimes share our interests, all without the use of lasers.

Knowing bush... (-1, Offtopic)

Anonymous Coward | more than 9 years ago | (#10827339)

he will turn the lasar from a communication laser into a blasting Iran or whereever there is oil.

The obvious thing to say is... (4, Funny)

hunterx11 (778171) | more than 9 years ago | (#10827347)

Suck on this, inverse-square law!

Free laser surgery... (1)

decipher_saint (72686) | more than 9 years ago | (#10827354)

Just aim your telescope at Mars and hope someone miscalculates the reply message coordinates.

BZAP!

Neutrinos (1, Informative)

Anonymous Coward | more than 9 years ago | (#10827392)

The ultimate system for communications would be using neutrinos. Only two downsides. One producing enough neutrinos to create a signal and coming up with a compact means of detecting them. With current technology it would probably take a detector the size of a football field to recieve a binary SOS and the only major source of them are events like super nova. The benefits would be enormous given a single signal from a single point could reach the entire planet passing directly through the earth with little or no loss. It's doubtful there will ever be a practicle way of doing it but it would be a way of sending a signal with little interference except for naturally occuring neutrinos.

Answered ... (1, Funny)

Anonymous Coward | more than 9 years ago | (#10827393)

"Does this mean we will soon have telescopes outside of our homes soon to pick up high definition TV signals instead of our current 18 inch dishes?" Yep, I looked into the near-future

No. (-1, Troll)

Lord Kano (13027) | more than 9 years ago | (#10827397)

Does this mean we will soon have telescopes outside of our homes soon to pick up high definition TV signals instead of our current 18 inch dishes?

Somebody let me know when science develops a way to eliminate stupid questions.

LK

It's a pretty cool idea. And I really like the way (3, Interesting)

multiplexo (27356) | more than 9 years ago | (#10827408)

they're getting more use out of the big scope at Palomar. Both Palomar and Lick, which until the 1980s housed the largest telescopes in the world (200 inch and 120 inch respectively) have been impacted by light pollution from encroaching urban areas and air pollution. But here's a way to use these scopes for something that can't be affected much by either. Cool!

Well, OK (5, Informative)

Anonymous Coward | more than 9 years ago | (#10827438)

Hams object, not because it's a good and valid method of delivering bits, but because it interferes with emergency communications.

There's lots of ways to get good Internet feeds to folks; just look at what Robert X. Cringely has done with 802.11b. Look in the archives of his columns at www.pbs.org and see there are untapped alternatives.

To understand why we're concerned, go switch your hi-fi to AM, tune to a vacant spot between stations, and turn up the volume about half way. Then, try to have a phone conversation over a bad cellular connection with your ear six inches from the speakers, and you will still have an easier time communicating than hams will when we experience the 16 db over S9 interference already demonstrated by BPL.

I will make a small wager with you, shaka999. If you live within North America, I'll wager your state's or province's emergency plan counts on hams. So does your county's emergency plan, and your city's.

You see, hams _practice_ at getting data through emergency conditions. We do it at our expense, with equipment we buy, build and maintain ourselves, without government funds.

There's even a subsection of every national ham organization dedicated to emergency services. Yeah, I belong to one, and was out in the last ice storm, two months ago, delivering nurses to the local hospital because the roads were otherwise impassible, and the locals had already overloaded the cellular network to the point where a fast busy tone or "All Circuits Busy" signal was as likely as dial tone.

BPL threatens the entire ability to function on the frequencies needed the most for long-range communications, the HF bands. If this interfered with TV (VHF and UHF), well, everyone would kvetch, but instead the power companies have designed these systems to use HF (aka shortwave) frequencies.

Long range radio relies on HF, because it takes those lower frequencies to effectively bounce off the inner layer(s) of the ionosphere. Higher frequencies (VHF, UHF, SHF, microwave) just zip right through the F, F1 & F2 layers, so we can't do bank shots to get a signal from Earthquakestan to Resourceland to let them know how many units of Type A to send.

Satellite? Well, gee, that presumes the ground stations survived that quake/tornado/hurricane/typhoon, that the power didn't fail, and the phone lines to the earth station still work. Oh, yeah, and IF there's a free satellite channel for us, which NASA's problems have not made any easier.

Now, America's three-quarters of a million hams are not alone here, as you make it seem. The NTIA (National Telecommunications and Information Administration), who you'd expect to be gung-ho over more bandwidth to previously underserved areas, and also FEMA (Federal Emergency Management Agency), have gone on record to object. They document that BPL was a complete disaster, interference-wise, when tried in Japan. The Austrian trials are on hold because the power companies there were not able to rein in the interference.

But, it's Politics with a Capital P; who is beholden to whom, and who bought whom.

Now, you might say, 'well, if there's a disater, the power's down, right'? Not necessarily. BPL can cause interference for miles and miles, but if a hospital needs to call for blood, what's the power company supposed to do, shut down the entire grid?

Besides, remember that hams buy their own gear to practice and learn with. If we can't use HF, well, no one will buy new HF gear, no one will learn the tricks of HF (which is _very_ different than the skills needed for the garden-variety, talk-around-town two meter and 70 cm band users), and no one will bother to keep the automated packet netowrks in service, the digital backbones of the ham world which move the vast majority of message traffic.

Sometimes, _nothing_ but Morse ("the original digital") will get through, but with BPL jamming the HF spectrum, morse will become a dead letter.

I mean, man, you can put a bra on Michael Powell, and yuk it up all you want (see URL) but, damnit, these changes will *kill* people.
http://www.wweek.com/story.php?story=4858

Hmm... (2, Funny)

flamechocobo (792168) | more than 9 years ago | (#10827444)

*walking along street* Hmm hmm hmm hmm hmm (humming a tune)... Wha? *looks up* AUUGGGHHHH!!! MY EEEEEEYEEEEESSSSS!!!

The benefits of lasers (4, Funny)

Fussen (753791) | more than 9 years ago | (#10827456)

When you add lasers to anything, the net benefit is multiplied by %5555. Interstella 5555 is a prime example.

Ninjas also benefit from lasers ovbiously.

Re:The benefits of lasers (0)

Anonymous Coward | more than 9 years ago | (#10827477)


Ninjas also benefit from lasers ovbiously.

Rubbish, Ninjas benefit from microwaves!

Obligitory... (-1, Offtopic)

IBeatUpNerds (827376) | more than 9 years ago | (#10827463)

I, for one, welcome our new interplanetary laser communication overlords.

and

Man, how I'd like a beowulf cluster of these babys!

Grab Your Tinfoil Hat (0)

Anonymous Coward | more than 9 years ago | (#10827474)

Obviously NASA doesn't wany anyone eavesdropping on all the nifty hi-res pictures they intend to take of all the alien tech laying around on Mars. Hey, if flying saucers have crashed on Earth, why not there, too?

re: radio dishes (1)

pyth (87680) | more than 9 years ago | (#10827518)

No. Broadcast is difficult with lasers, you fool.
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