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NASA Probe Blasts 461 Gigabytes of Moon Data Daily
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.
Their Cingular bill is going to suck.
But can it learn to love?
SJW: Someone who has run out of real oppression, and has to fake it.
I'm sure you can still beat the moon in latency.
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?
If I have nothing to hide, don't search me
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
But of course, "In Space, No One Can Hear You Spam"...
Now the internet is a series of vacuum tubes?
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.
Do you have ESP?
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.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
Anybody else think it's funny that in this case, a vacuum tube is a step up from a transistor?
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.
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.
* Carthago Delenda Est *
Tomorrow's headline: "RIAA Lobbies Congress to Shut Down NASA"
-William Brendel
"Traveling Wave Tube Amplifier" is the most silly name I have ever heard for a can of Pringles :)
____
nico
Nico-Live
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.
First rule of holes; When in one, stop digging.
Comment removed based on user account deletion
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.
Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
The best available at my house is 512Kbs DSL. I offered to lay the fiber myself for the final 2 1/2 miles or so, or pay them to do it, but they insist that there are legal reasons they can't serve me.
So, in typical geek fashion, I set up a P2P wifi link for that distance. It works, and I get about 50 Mbs on a good day. I get terrible packet loss when it rains hard, though.
Learn about Photography Basics.
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!
Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
Since it's orbiting I expect that it has a blackout period similar to that encountered by the Apollo spacecraft. Makes sense that it would have as fast a link as possible to offload data before the next blackout period.
All this talk about bandwidth, I'm more interested in the amount of storage space needed back here on earth to store all that data being transferred. 461GB of data per day is around 3.2TB of data per week or a little less than 1.7 Petabytes of data per year (I think.. if my math is correct). Once you add in all of their other storage needs that's one hell of a SAN.
...and asks for astronomical damages to be paid?
Ezekiel 23:20
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.
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.
if this is supposed to be a new economy, how come they still want my old fashioned money?
curious thing about tubes, they don't become useful until they're sealed in vacuum, and boiled out in a high RF magnetic field to take impurities off the elements. and then you have to flash the last of the gases off by igniting a getter inside the envelope.
that provides a higher vacuum on earth, inside the tube, than you can ever develop in space. and the electrons can do their work, instead of hitting stuff and just making a useless glow.
if this is supposed to be a new economy, how come they still want my old fashioned money?