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Quad Lasers Deliver Fast, Earth-Based Internet To the Moon
A joint project involving NASA and MIT researchers had demonstrated technology last year that could supply a lunar colony with broadband via lasers ("faster Internet access than many U.S. homes get") and has already demonstrated its worth in communications with spacecraft. From ComputerWorld's article: "The Lunar Laser Communication Demonstration (LLCD) kicked off last September with the launch of NASA's LADEE (Lunar Atmosphere and Dust Environment Explorer), a research satellite [formerly] orbiting the moon. NASA built a laser communications module into LADEE for use in the high-speed wireless experiment. LLCD has already proved itself, transmitting data from LADEE to Earth at 622Mbps (bits per second) and in the other direction at 19.44Mbps, according to MIT. It beat the fastest-ever radio communication to the moon by a factor of 4,800." Communicating at such distances means overcoming various challenges; one of the biggest is the variability in Earth's atmosphere. The LLCD didn't try to power through the atmosphere at only one spot, therefore, but used four separate beams in the New Mexico desert, each aimed "through a different column of air, where the light-bending effects of the atmosphere are slightly different. That increased the chance that at least one of the beams would reach the receiver on the LADEE. Test results [were] promising, according to MIT, with the 384,633-kilometer optical link providing error-free performance in both darkness and bright sunlight, through partly transparent thin clouds, and through atmospheric turbulence that affected signal power." At the CLEO: 2014 conference in June, researchers will provide a comprehensive explanation of how it worked.
"faster Internet access than many U.S. homes get"
That's not hard to do. In the United States, our high speed Internet is much like our high speed rail...
The moon, eh? This will be important when we get around to mining the moon into a block of Swiss cheese for whatever mineral riches it possesses. I predict China will be the first, and we Americans will follow soon after they have opened the door.
If you want news from today, you have to come back tomorrow.
Fuck everything, we are doing five beams!!!
Life is not for the lazy.
So show of hands here, who has a 622 Mbps at home? That's right, as of this article, your "last mile" officially sucks more than LADEE's last 250,000 miles
Just because you're paranoid doesn't mean they aren't out to get you
No one can defeat the quad laser. The bullet is enormous, there is no escaping.
their last one
Readers here should know that LADEE was crashed into the moon more than a month ago. Yes, NASA did research on laser communication using LADEE, but reporting it in present tense is misleading. (...and the last Slashdot article on LADEE incorrectly reported where it crashed.) Previous Slashdot articles already reported the laser communication research.
NASA can't even afford a decent space telescope, so why would anybody think they can afford to build a lunar colony that would require such as laser system ?
Well since the dominating factor in earth-moon communication is the speed of light with 2.6 seconds round trip you'll never have decent latency anyway, for the same reason we'll never have global FPS servers working well. Halfway around the the earth (20000 km) with light going about 2/3c in fiber optics is 100 ms just here on earth. And Mars is 8-40 minutes away round trip, which is a far more likely site for a colony. That said, if you were stuck in a cramped little base - the initial versions will probably make prisons look spacious - at least you'd have the latest Game of Thrones to watch.
Live today, because you never know what tomorrow brings
If you ever have extended occupancy a computer geek, and 8 lbs of discretionary cargo, there will be a game server on the moon. Maybe a few more pounds if you need your own power source.
gaming's going to suck
On the other hand, PR0N is going to rock! :-)
Lisias@Earth.SolarSystem.OrionArm.MilkyWay.Local.Virgo.Universe.org
Incoming power at the satellite is stated as a nanowatt. I'm pretty sure this puts it way below the threshold of most, if not all, solid state optical detectors. I'm thinking some kind of FAST photomultiplier tube, but I really have no idea. Any thoughts?
Think of using something like this to transmit terrestrially through air of many miles/kilometers distance RELIABLY rather than the one or (if you're lucky) two you get today: it would be a godsend and could replace a LOT of metro microwave (depending on which city and its local climate, of course) without having to lay fiber. Its the unlicensed holy grail, really.
On the other hand, PR0N is going to rock! :-)
Low gravity boobs and ceiling stains?
But wouldn't it be easier to have a satellite on earth orbit that was locked on the same apparent orbit than moon and then transmit data through that. By communicating with that satellite using radio and then from that satellite to moon using laser you wouldn't have to work the laser through the atmosphere and after you establish a stable station on moon with a line of sight to earth you would have a continuous beam channel going.