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NASA's LLCD Tests Confirm Laser Communication Capabilities In Space
An anonymous reader writes "This week, NASA released the results of its Lunar Laser Communication Demonstration's (LLCD) 30-day test carried out by its Lunar Atmosphere and Dust Environment Explorer (LADEE) that is currently in orbit around the Moon. According to the space agency, the LLCD mission proved that laser communications are practical at a distance of a quarter of a million miles and that such a system could perform as well, if not better, than any NASA radio system."
Does this make what SETI is looking for pointless? Should they instead be looking for lasers if they work better for communication.
cat, just because we dont have a large manned space program does not mean we dont have a space program. I would say that we have found out more about space and moons and planets and stars in the previous 10 years than at any time in the past. Sure it is not as flashy as sending an astronaut to the moon or mars, which I am in agreement with you that we need to be working harder on our manned missions, but to say our space program is dead is just simply wrong
have you seen my sig? there are many others like it but none that are the same
SETI is about detecting ambient electromagentic waves that may be of an "intelligent" origin. Lasers, however, are a specific form of electromagnetic wave. So in some sense, SETI is already looking for them.
Now, lasers used for communications like this are of the utmost quality. Their dispersion (that is, how much the beam of light separates over time and distance) is very minimal. While a flashlight may have a large dispersion measured in meters a few centimeters from the light source, lasers used for communications usually have a dispersion of less than a tenth of a millimeter over hundreds of thousands of kilometers. This means that we're looking at dispersion of only a few millimeters after millions of kilometers. Even after traveling billions upon billions of kilometers, the dispersion is still measured in only a handful of meters.
Since there's so little dispersion of our modern-day high-quality laser beams, and it's likely that any other "intelligence" could very well have lasers far superior to ours, trying to detect them would be very, very difficult unless you're at the specific location you were targeted at. It's very unlikely that the laserbeam, given its relatively small size, would directly it a SETI detection device.
To put things in perspective, imagine that you're standing at one end of a football field. Then imagine your friend is at the other end. Your friend has a sewing needle, and is somehow able to throw it at you over that distance. The likelihood of SETI successfully capturing an arbitrary laser-based communication signal is still far, far less probable than you catching the sewing needle thrown by your friend from 100 meters away directly in your penis' urethra. I hope that puts it in perspective.
SETI should keep doing what they're doing, because while it's similar in nature to what'd be needed to detect laser-based signals, there's still the probability that any "intelligence" out there may have discovered radio technology first, and they are transmissions that are far easier and much more likely to be detected by non-target receivers.
...dealing with telepathic cats.
cat, just because we dont have a large manned space program does not mean we dont have a space program. I would say that we have found out more about space and moons and planets and stars in the previous 10 years than at any time in the past. Sure it is not as flashy as sending an astronaut to the moon or mars, which I am in agreement with you that we need to be working harder on our manned missions, but to say our space program is dead is just simply wrong
I hope this is not one of those five year technologies.
Slashdot is full of stories about this new technology and that new technology that will be ready in five years. These then just vanish after the story first appears.
After the story is published and we comment, it is forgotten and nobody is held accountable for publishing bullshit.
Maybe someone should do a review of stories published 5 years ago of new technologies that have never materialized. I remember five years ago there used to be so many stories of new storage technologies about storing in DNA, some crystal lattices. nano-structures and so on.
Sure it is not as flashy as creating an Immanuel Goldstein out of a nation that's not really such a threat to us, that we often armed and trained first, then spending many times the resources in order to go overseas to shoot up and blow up some brown people with unfamiliar names to keep the military industrial complex satiated, but to say our miniscule, neglected, space program (that no longer inspires the nation) is dead is just simply wrong
Fixed that for you. It must have really been something to have heard Kennedy declare that we choose to go to the moon, not because it is easy but because it is hard. A sense of purpose and a sort of pride that came from technical achievement and engineering marvels rather than the comparatively simple matter of sending the world's strongest military against some of the world's weakest militaries. This generation has nothing quite like that.
It is a miracle that curiosity survives formal education. - Einstein
Yes, but they won't have fins.
rewriting history since 2109
I remember 1961 fondly. I was 31 then. You need to understand that those were very different times. That was pre-Boomer America, which I can assure you was much better than the post-Boomer America we have to deal with now. I'm not looking back through rose-colored glasses, either. The people and accomplishments speak for themselves.
Back then, America was a meritocracy. Those who were were good, regardless of origin or background, succeeded. Those who were great excelled. Those who couldn't were rightfully shunned. Resources were funneled to those who could accomplish great things. And as would be expected, great things were accomplished. July 20, 1969 is a perfect example of this.
But then the Baby Boomers came onto the scene in the mid-1960s. It's safe to say that, as a generation, they have managed to destroy America. Coming from unearned privilege, they did not realize the importance of merit and hard work. Everything was just handed to them. They extended that mentality to everything they got involved with.
As time progressed, Boomers got involved with government and business. Rather than being a limited tool to help society achieve initiatives where the direct financial profit may be small or nonexistent, but the social benefits still large nevertheless, the Boomers converted government into a vehicle for handouts.
Just look where we are today, thanks to the Boomers. Their ruination of government now results in huge sums of money going toward poor, useless, dumb-as-dirt Southerners who waste it on junk food. Then there's the so-called "corporate welfare" going to inefficient, uncompetitive private enterprises. Meanwhile, the budgets of NASA and other actually useful organizations have been slashed to nearly nothing.
Baby Boomers do not know how to properly allocate resources, and that's why so much of America's economy is in turmoil, and its scientific research capabilities severely compromised. Baby Boomers, in a single generation, managed to destroy what was the most productive and capable society that has ever existed. It's one of the greatest shames of history.
Not really sure what any of what you just said had to do with what I was saying. Good attempt to paint what I said into something political when it was in fact not. I am a firm believer that we should be spending more on nasa, a good 5X-10X more than what we do.
have you seen my sig? there are many others like it but none that are the same
By golly if we can put a laser for communicating in space we should be able to put a laser for communicating on a cell phone!
I give you: http://theplayzer.com/
Ah, just to clarify - the space race was most definitely a military endeavor. We show off our state-of-the-art ICBM technology (carrying a human payload into space) to the Russians, they do the same to us. Rinse and repeat until the Soviet Union imploded, at which point both space programs lost their military importance, and with it most of their funding.
It made for great PR films, but the people that cared about science, exploration, and pushing the boundaries of human accomplishment were always riding on the coat tails of the military. Once that stopped being possible it was really only the usefulness of satellites that kept us in space at all. They pay for the launch, and we mostly make do with whatever science we can squeeze in while we're up there.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
after I destroy Washington D.C... I will destroy another major city every hour on the hour. That is, unless, of course, you pay me... one million dollars
It isn't unusual to see argue their point by appealing to a work of fiction, such as Randians making references to Atlas Shrugged, but I think this is a first for me to see someone argue a point by appealing to I Dream of Jeanie!
That's always been a cute fairy tale put forward by the Pentagon fantasy factory, but it's never been true. The military assisted in the space race, especially in the beginning when they had the only functional launchers, but the necessities of space exploration quickly surpassed the really rather primitive needs of the military. The Apollo 1 booster was already larger and more powerful than any ICBM would ever need to be, and took so long to assemble, prep and fuel that it could never be useful as a weapon. The Pentagon never needed a booster powerful enough to send a 700 kilo spacecraft to the edge of interplanetary space, much less send two spacecraft and an electric car to the moon, nor did the Kremlin.
Von Braun and Korolev worked on military projects during the first part of their because that was the only way they could get funding. They achieved their greatest accomplishments working on the civilian programs. Von Braun made no secret that the Moon had always been his goal, and Korolev upbraided a Kremlin general that wanted to usurp some of his funding by telling him, "These rockets are much more important to our future than your missiles."
"Think about how stupid the average person is. Now, realise that half of them are dumber than that." - George Carlin
...porn will be readily available on the Moon and beyond and we can always take a troll through deep space.
What happens when you have to replace the gbic-equivalent on the moon???
Circle the wagons and fire inward. Entropy increases without bounds.