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Moon NASA Shark Science

NASA Achieves Laser Communication With Lunar Satellite 99

New submitter EngnrFrmrlyKnownAsAC writes "Communicating with lasers has become the hot new thing. While most researchers are seeking faster throughput, NASA set its sights in a different direction: the moon. They recently announced the first successful one-way laser communication 'at planetary distances.' What did they send? An image of the Mona Lisa, of course. 'Precise timing was the key to transmitting the image. Sun and colleagues divided the Mona Lisa image into an array of 152 pixels by 200 pixels. Every pixel was converted into a shade of gray, represented by a number between zero and 4,095. Each pixel was transmitted by a laser pulse, with the pulse being fired in one of 4,096 possible time slots during a brief time window allotted for laser tracking. The complete image was transmitted at a data rate of about 300 bits per second.'"
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NASA Achieves Laser Communication With Lunar Satellite

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  • 300 bits per second? (Score:4, Interesting)

    by SternisheFan ( 2529412 ) on Saturday January 19, 2013 @06:09PM (#42635531)
    No budget left over to get FIOS?
  • What about Lenna? (Score:5, Interesting)

    by ericcc65 ( 2663835 ) on Saturday January 19, 2013 @06:32PM (#42635623)

    The Mona Lisa? Are you serious? Way to break tradition NASA, my heart weeps for Lenna: []

  • I don't get it... (Score:2, Interesting)

    by Charliemopps ( 1157495 ) on Saturday January 19, 2013 @07:34PM (#42635919)

    They have mirrors on the moon, that we routinely bounce lasers off of to measure distances and do Relativity experiments with. It's suddenly difficult to transmit information via laser? Why so slow? Why was this an accomplishment?

  • Fermi Paradox (Score:5, Interesting)

    by yanom ( 2512780 ) on Saturday January 19, 2013 @08:43PM (#42636291)
    If laser communication overtakes radio for our own space equipment, it might explain the Fermi paradox - we cannot detect alien civilizations because the communicate with lasers (emitting no radio signals at all), making them undetectable to those not in the path of the beam.
  • by Anonymous Coward on Saturday January 19, 2013 @09:42PM (#42636519)

    As I've been saying for years SETI doesn't have a hope in h**l finding the aliens because they use the much more efficient point to point message casting as opposed to the broadcasting in every direction used here on earth. Why use the inefficient method sending your message/data/... everywhere when it is really only destined for 1 place.

    I think in 100 years we'll look back and see that the use or radio and the inefficient broadcasting methods was a short segment in our history. It will likely be the same for other developing races.

    I recall a few years back they actually found something that looked like real alien communication. It couldn't be captured again. Of course it coul'n't be found again. We were no longer behind the target of the message beam.

  • by dissy ( 172727 ) on Saturday January 19, 2013 @11:06PM (#42636833)

    Would you like to play a game?

    0. What is your FidoNet node address?

    1. What number of in & out dials have you?
    7 / 1 (8 chans of a frac pri)

    2. What is the land area coverage of an unladen local call?
    About half of the area code, guessing 100 square miles?

    I never understood why some parts of 614 were local but others were long distance, while at the same time a small part of 740 was local to me yet a different area code.
    I had to route mail to another board across town in 614, where he could reach the other half of 614 locally, just to avoid minutely charges.

    My 8 PRI channels were to my home (well, to my parents home at the time) and mostly for dialin. I rocked Oblivion/X by the time I was on fido. One line floated for scheduled callouts, but none dedicated to that.
    Once I discovered the Internet in '89, first one then later two channels were dedicated to PPP.
    By '92 I was getting less than 5 calls a day to the board, and shortly converted my whole frac PRI to be dedicated Internet, and I pretty much gave up the sysop role for good in exchange for EFnet as things turned out. Even ran an efnet server for a short time back in '95 i think it was.

    While I can say for certain that communications have only changed for the better as far as the Internet goes, there is still a lot I miss from those days, even though I wouldn't want to go back to that for anything.

Exceptions prove the rule, and wreck the budget. -- Miller