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An Interplanetary Laser Communications System
caffiend666 writes "A news article at Yahoo states NASA is planning on testing the first laser-based interplanetary communications system on the Mars Telecommunications Orbiter to be launched in 2009. 'Unlike radio frequency signals that wash over the entire Earth, Fitzgerald and his colleagues will be shooting for a much smaller target - the southwestern corner of the United States.' Does this mean we will soon have telescopes outside of our homes soon to pick up high definition TV signals instead of our current 18 inch dishes?"
Does this mean we will soon have telescopes outside of our homes soon to pick up high definition TV signals instead of our current 18 inch dishes?"
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No.
Because for television broadcast to the general population you want to wash the signal over the whole earth, rather than trying to target each receiver. And if you think your reception sucks when it's raining out now. .
KFG
Does that mean that something like this might be in widespread use in advanced alien civilizations, and SETI has no chance of ever finding anything?
Technoli
Its unlikely because Optical Telescopes rely on somewhat precise pieces of equipment such as lenses which are not known for their 'year-round' hardiness.
Speaking from experience, line-of-sight laser communications systems can be a right-royal pain to keep maintained when they are within meters.
I don't know for sure, but I would image that initial targetting of your telescope would be a very tricky operation (and you know that sat dishes are hard enough). And then, once installed, the fixings would need to be exceptionally heavy-duty to hold the telescope on target during gales etc.
Ripping an new rectum in the fabric of spacetime.
Here's a story about an ambitious plan to build a laser-based interplanetary communications network and the only thing the story submitter is concerned with is how this will influence his TV reception.
This, my friends, is why the human race is doomed. Here on slashdot, where we care more about science than most people, all some people can think about is how a new technological advancement can facilitate the transmission of market-research-constructed-SitComs or advertisements for the latest yuppie gizmo to their home.
Perhaps I need to read TFA more closely, but I am left wondering what the advantages of using lasers for interplanetary communications would have over our traditional RF or microwave systems. After all, it's all EM radiation, so it's speed of light, and the lasers they're using apparently can't reach through clouds, so what are the reasons why you would want to use lasers instead of radio antennas?
Sleep is futile.
Yes they're all the same without difference. Everything is light. That is why they are using visible EMR instead of X-rays in hospitals. It's all the same and should be called the same!
Actually, he lives across the street from The Beast.
664 and 668 live next door.
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