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NASA Moon Space

NASA Probe Blasts 461 Gigabytes of Moon Data Daily 203

Posted by CmdrTaco
from the thats-a-lotta-bits dept.
coondoggie writes "On its current space scouting mission, NASA's Lunar Reconnaissance Orbiter (LRO) is using a pumped up communications device to deliver 461 gigabytes of data and images per day, at a rate of up to 100 Mbps. As the first high data rate K-band transmitter to fly on a NASA spacecraft, the 13-inch-long tube, called a Traveling Wave Tube Amplifier, is making it possible for NASA scientists to receive massive amounts of images and data about the moon's surface and environment. The amplifier was built by L-3 Communications Electron Technologies in conjunction with NASA's Glenn Research Center. The device uses electrodes in a vacuum tube to amplify microwave signals to high power. It's ideal for sending large amounts of data over a long distance because it provides more power and more efficiency than its alternative, the transistor amplifier, NASA stated." It kills me that the moon has better bandwidth than my house.
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NASA Probe Blasts 461 Gigabytes of Moon Data Daily

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  • Insane (Score:5, Funny)

    by DoofusOfDeath (636671) on Thursday August 20, 2009 @08:33AM (#29132069)

    Their Cingular bill is going to suck.

  • by elrous0 (869638) * on Thursday August 20, 2009 @08:34AM (#29132073)
    But can it learn to love?
  • by Shin-LaC (1333529) on Thursday August 20, 2009 @08:34AM (#29132075)
    I'm sure you can still beat the moon in latency.
  • Hope they don't try anything over bittorrent.. that could add a bit of latency
  • by corsec67 (627446) on Thursday August 20, 2009 @08:36AM (#29132101) Homepage Journal

    It may have better BW than your house, but the ping is going to suck.

    Or would you like your internet connection to be served by a SUV carrying hard drives?

    • How many hard drives are we talking about here?
      • And can I keep the hard disks???

    • by dissy (172727) on Thursday August 20, 2009 @08:55AM (#29132317)

      Or would you like your internet connection to be served by a SUV carrying hard drives?

      Never underestimate the bandwidth of a fedex truck packed with 250 lbs of hard disks!

      Depending on the file size of what you would be downloading and with what technology, overnight shipping might STILL be better latency too!

      • Re: (Score:3, Funny)

        by snookums (48954)

        Or would you like your internet connection to be served by a SUV carrying hard drives?

        Never underestimate the bandwidth of a fedex truck packed with 250 lbs of hard disks!

        Depending on the file size of what you would be downloading and with what technology, overnight shipping might STILL be better latency too!

        Right, but remember that full hard drives weigh more than empty ones, so you only want to buy about 200 lb of empty drives if you have a 250 lb limit.

  • better bandwidth? (Score:3, Informative)

    by erbbysam (964606) on Thursday August 20, 2009 @08:39AM (#29132125) Homepage
    It may have better bandwidth, but I hope you have less latency then the 1.25 sec on the moon(1).

    1 - http://www.vendian.org/envelope/dir0/light_delay.html [vendian.org]
  • Spam (Score:3, Funny)

    by tsdguy (991042) on Thursday August 20, 2009 @08:39AM (#29132127)
    But of course, "In Space, No One Can Hear You Spam"...
    • "In space, no one can eat ice cream"? (One of the not best b grade movies)

      And what the hell? Vacuum tubes over transistors? Seriously? Are they super vacuum-ized because they are used in the vacuum of space? Makes me think of one of those medical shows where a surgeon is like "we need more suction". Vacuums FTW!

      • Re:Spam (Score:4, Informative)

        by Anonymous Coward on Thursday August 20, 2009 @09:29AM (#29132749)

        Vacuum tubes have always had higher frequency limits than transistors, since WWII in fact. Take a look at THz radiation sources, all tubes. No tranny is going to touch that for a while. And then tubes will have gotten better too.
        http://en.wikipedia.org/wiki/Backward_wave_oscillator
        Tubes just have more geometric freedoms to create bizarre fields and strange structures to do whatever you need.

      • by Gordonjcp (186804)

        And what the hell? Vacuum tubes over transistors? Seriously?

        Seriously. Pretty much all television transmitters use klystron valves - transistors are only used for very low power transmitters, typically below 25kW output.

  • So wait... (Score:3, Funny)

    by Anonymous Coward on Thursday August 20, 2009 @08:39AM (#29132129)
    Now the internet is a series of vacuum tubes?
  • by Manuka (4415) on Thursday August 20, 2009 @08:40AM (#29132135)

    Traveling Wave Tubes have been a mainstay of microwave communications and radar systems for the better part of a century. They're a very efficient way of amplifying microwave signals to the very high power levels needed to cross long distances.

  • by Trailer Trash (60756) on Thursday August 20, 2009 @08:43AM (#29132175) Homepage

    It kills me that the moon has better bandwidth than my house.

  • Radar (Score:4, Interesting)

    by flyingfsck (986395) on Thursday August 20, 2009 @08:47AM (#29132215)
    They are using a radar set as a data link. I'm wondering whether they are still using it as a radar to map the moon too, by using a different set of antennas.
    • Well, as it happens, yes, the LRO does have a Synthetic Aperture Radar payload (called MiniRF).

      But it's separate.

  • by dunelin (111356) on Thursday August 20, 2009 @08:52AM (#29132271)

    Anybody else think it's funny that in this case, a vacuum tube is a step up from a transistor?

    • Re:Vacuum Tube? (Score:4, Informative)

      by confused one (671304) on Thursday August 20, 2009 @09:21AM (#29132635)
      vacuum tubes are common in high power applications
    • Re:Vacuum Tube? (Score:5, Informative)

      by Andy Dodd (701) <atd7&cornell,edu> on Thursday August 20, 2009 @09:25AM (#29132705) Homepage

      When you need to make serious power, tubes are still the way to go. Transistors have a significant reliability benefit.

      Also, for 99% of applications, transistors are better. For the other 1%, you have very application-specific tube designs such as TWTs and magnetrons, which rearrange the tubes in such a manner as to negate its usual disadvantage (large size USUALLY translates to nasty frequency limits - TWTs and magnetrons are exceptions that use various Neat Tricks to allow microwave operation from a large device.)

      BTW, one of the other common microwave tubes (magnetrons), while it is a "niche" device, it is a VERY widely deployed niche - basically all microwave ovens use magnetron tubes.

    • Re: (Score:3, Insightful)

      by Lumpy (12016)

      no because they always have kicked the arse of a transistor.

      Show me a 10,000 watt transistor.. Oh wait, you haveto use a Tube for that kind of power....

      Tubes have kicked the Transistors butt forever when you need high power comms.

    • by darkonc (47285)
      Yeah, but what happens if the vacuum tube springs a leak? That's always been a problem with vacuum tubes. I mean it's not like someone is going to do a house call in lunar orbit.
      :-)
  • Vacuum (Score:5, Interesting)

    by Anonymous Coward on Thursday August 20, 2009 @08:53AM (#29132281)

    Did they even bother to seal the tube, or are they using the vacuum of space?

  • You just KNOW that the original name for the device was "Traveling Wave Amplified Tube" until some NASA jackass noticed the acronym and ruined it for everyone.
    • by goodmanj (234846)

      Dammit, you stole my joke. :(

    • by MadCow42 (243108)

      At an old company, our lead tech kept talking about how to configure one of our digital scanners, using the acronym for "Scanner Look-Up Table"... even writing it in big, bold letters on the board. Being a 50+year-old Vietnamese guy, it didn't mean anything to him, and he just kept on going.

      We peed ourselves laughing... our boss didn't when he walked into the room to see a huge "SLUT" written on the board. :)

      MadCow.

    • by argStyopa (232550)

      Probably because someone told him "But Bill, we named it after you!"

      Which didn't help either.

  • That much data and Comcast would throttle it no matter what the scientists said. If AT&T had it going through their "unlimited" 3G connection, NASA would be hosed and we would be increasing the national debt by trillions.

    One last thing, I m wondering if the **AA doesn't want access to the data stream to make sure it isn't a bittorrent containing their precious copyrighted work. After all, we all know there is no legitimate use for that much bandwidth.

  • Silly name (Score:2, Funny)

    by nsebban (513339)
    "Traveling Wave Tube Amplifier" is the most silly name I have ever heard for a can of Pringles :)
  • by TheHawke (237817) <{rchapin} {at} {pelicancoast.net}> on Thursday August 20, 2009 @09:16AM (#29132549)

    TWT amps have been used in microwave systems since the 2nd world war. The use of TWT in satellites are recent, as in 25-30 years ago. The NSA's LACROSSE and the new ONYX satellites use TWT amps in the finals on their radar systems. The Soviet ROARSAT's probably use them as well, or something similar, they love to overbuild their stuff.

    Hell, the YF-12a used 2 TWT's in tandem in its Hughes AN/ASG-18 radar, putting out over 10MW of raw power.

    But they are power gobblers, The YF-12A's ate over 40KVA of juice to operate.

    • by stefanb (21140) *

      The use of TWT in satellites are recent, as in 25-30 years ago.

      Huh?! Traveling-wave tube [wikipedia.org]:

      On July 10, 1962, the first communications satellite, Telstar 1, was launched with a 2 W, 4 GHz RCA-designed TWT transponder used for transmitting RF signals back to the earth. Syncom 2, the first synchronous satellite (Syncom 1 did not reach its final orbit), launched on July 26, 1963 with two 2 W, 1850 MHz Hughes-designed TWT transponders (one active and one spare).

    • by evilviper (135110)

      The use of TWT in satellites are recent, as in 25-30 years ago.

      30 years ago is recent in satellite tech? As opposed to those 200 year-old satellites up in orbit, propelled by horse and buggy...?

  • I'm sure you could get that kind of bandwidth at your house, too, if you paid enough for it.
  • not only does the moon have faster data transfer rates than your house, but often times its transmitting far more interesting and pertanent data than the connection at your house.

    unless 4chan has a section for materials science and physics now?
  • by pz (113803) on Thursday August 20, 2009 @10:00AM (#29133079) Journal

    CmdTaco comments in the original posting:

    It kills me that the moon has better bandwidth than my house.

    I know that Taco's trying to be funny here, but, seriously, the moon should most certainly have better bandwidth. That is to say, a research project that is able to afford a custom solution to a highly specialized problem with plenty of money to throw at had damned well better have better performance than what is available to commodity markets. I expect this to be true just as nearly every other bit of the hardware they send up will be better, faster, stronger, lighter, and more able to withstand ionizing radiation than the equivalent, when available, from K-Mart. There's a good reason these projects cost hundreds of millions of dollars for a probe to be sent somewhere. The Mars rovers, as another example, are using a 256 kbps channel -- deployed five years ago when DSL was still considered fast -- over a distance that ranges 55 to 400 million miles. Now *that's* performance.

    It actually rather amazes me that Taco's or anyone else's house has close to the bandwidth available from the moon.

    • by brusk (135896)
      Also, it kills me that the rocket that took the LRO up there goes faster than my car.
  • It kills me that the moon has better bandwidth than my house.

    That why its called "Rocket Science".

  • Tone (Score:3, Funny)

    by kheldan (1460303) on Thursday August 20, 2009 @10:46AM (#29133735) Journal

    Traveling Wave Tube Amplifier

    ..and there's always the advantage of having data with a warmer, richer feel to it than using a solid-state amp. Just think how much better the data will be once they start storing it on vinyl!

  • Now we only need to know how many Library of Congress can be transfer each day?
    or should we switch our Library of Congress unit to Data transmitted per day from the Moon?

  • by peter303 (12292) on Thursday August 20, 2009 @01:03PM (#29136005)
    In fact the limited factor is recording speed and capacity. The large atom-smashers run the receptor data through a preliminary A.I. discrmination programs which save the small fraction deemed interesting. Then slaving grad students will spend years on tiny pieces extacting the significant discoveries.

    Some of the large ground telescopes are partnering with Google and MicroSoft to put large portions of their data online. The computer programs and main scientists only have enough time to give a cursory glance at it. Maybe it will be a kid in a junior high school science lab that looks at something more closely and makes a discovery. Some of this is occuring with google earth imagery now.
  • by swschrad (312009) on Thursday August 20, 2009 @01:40PM (#29136479) Homepage Journal

    but for high power, squirrelly conditions, and reliability under real world conditions, tubes are still the go-to player in a lot of situations. a solar storm will roach semiconductor outputs, but it takes a monster pulse straight down the gullet to take a tube out.

  • It kills me that the moon has better bandwidth than my house.

    You wouldn't like the latency though.

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