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

Radar

[flyingfsck]

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.

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.

Vacuum

[Anonymous Coward]

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

Re:The moon vs. your house

[lwsimon]

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.

Does the math work?

[Anonymous Coward]

Or is this an example of someone not knowing bits versus bytes?

461 GB of data is 461*1024*1024*1024 bytes (yes, I do it right because unlike so many I understand storage) = 494,994,980,860 bytes. Times 8 for bits = 3,959,959,846,900 bits.

A day is 60*60*24 = 86,400 seconds.

# of bits claimed/# of seconds in day = 45,832,869 bps or 45,833 Kbps or 46 Mbps.

Yep, better than I get at home, too.

100 Mbps --> 8,640,000 Mbits/day, or 1,080,000 MB per day or about 1 TB/day possible bandwidth.

Re:Does the math work?

[minijedimaster]

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.

terabytes for Hadron Collider and large telescopes

[peter303]

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.