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.

Comments

Insane

[DoofusOfDeath]

Their Cingular bill is going to suck.

Re:Insane

[CecilPL]

Actually 10base is 10Mbps, or 1.25 MB/s.

5.46MB/s is close to half of a 100BaseT.

Re:Insane

[tomhudson]

Did anyone notice that it's all based on vacuum tubes?

My question is why you need a vacuum tube in a vacuum? Just put the parts out in open space, save a bit of weight, no problem with the tube getting deposits on it over time, or thermal expansion and contraction stressing the tube, etc.

Don't feel bad, CmdrTaco

[Shin-LaC]

I'm sure you can still beat the moon in latency.

This is not exactly a new device...

[Manuka]

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.

Re:This is not exactly a new device...

[aicrules]

The article admits that the Traveling Wave Tubes are not new, but it also lists several points that make this implementation better and very much noteworthy compared to its predecessors. You seem to have an interest in/knowledge of these communication devices, so I would say that the article is actually a worthwhile read for you.

Re:This is not exactly a new device...

[MiniMike]

That is the most eloquent "RTFA" I've ever seen...

Re:Sure, it can blast huge amounts of data

[shadowblaster]

Sure it can, after all it's got a 13 inch "tube".

Vacuum

[Anonymous Coward]

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

Traveling Wave Tube Amplifier?

[Spazholio]

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.

Re:Don't try this in Space

[wbren]

Tomorrow's headline: "RIAA Lobbies Congress to Shut Down NASA"

Re:Vacuum Tube?

[Andy Dodd]

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:Spam

[ovu]

I have never before heard a serious conversation pitting the respective benefits of trannys vs. tubes in this context...