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New Telescope Array Goes Live For SETI
The Skinny writes "Today is a historic day for the SETI program. The New York Times reports that astronomers are flipping the switch today on the Allen Telescope Array — 350 antennas, each 20 feet in diameter — which will, among other things, extend the search for extraterrestrial life a thousandfold. From the article: ' There are some 200 billion stars in the galaxy, and a significant fraction of them have planets. Estimates of the number of intelligent civilizations in the galaxy have ranged from one (or none, if you are particularly discouraged about human affairs) into the millions. Dr. Shostak calculated that the full Allen array would be able to detect a signal from as far as 500 light years that is only a few times more powerful than what can now be sent by the Arecibo radio telescope, a 1,000-foot-diameter dish in Puerto Rico that is the world's largest (although it is in danger of being shut down to save money). That translates to about a million stars, which he said was getting into a promising number. Dr. Shostak described the expanded search as looking for the needle in the proverbial haystack with a shovel instead of a spoon.'"
I think the better metaphor would be "trying to move a mountain with a spoon instead of a pen cap." Seriously, taking into account the number of stars, the number of planets orbiting the stars, and the span of time that they're likely to be spewing radio waves, the task is monumental compared to any resources that SETI may get. The work is still important, but let's not underestimate the task.
With 200 billion stars in OUR galaxy alone, and billions of other galaxies in our universe, anybody that thinks we are unique (usually religious type folks) are seriously fooled.
There has to be hundreds of thousands of life forms out there (at least). The sooner science finds it, the better.
IANAS but I think it will, sooner or later, catch some informations that can be useful to non alien-related studies
!sig
I always find it amusing when people say money is "wasted". If I took a stack of bill and burned them, or buried them never to be seen again, that would be wasting them.
If they spent $100mill on a telescope array, where did the money go? It went to some firms who do that, who in turn paid their employees and their suppliers, who paid their employees, etc. Those employees bought groceries, sent their kid to the dentist, sent their kid to college, bought a new car.. the money flowed through the economy. Assuming a large percentage of the firms and suppliers are in this country, then the money stayed in the national economy.
When the economy is flowing actively, more of those people downstream will be willing to donate their time and money to what you'd probably classify as "good things". When it slows down, or the Government is taking a big chunk at every step as taxes, then they'll be less inclined to do so.
I keep tellin em but they never listen. Aliens gave up on radio eons ago. Poor range, prone to interference, and a host of other disadvantages. If you want to eavesdrop on what's being said about us in the universe, you gots to gets your hands on one of them newfangled SHF gravity wave radios.
If I didn't have absolutely NOTHING to do, I wouldn't be here.
with a spoon, you could easily see the needle... with a shovel of a hay, the needle becomes a little more hard to see.
Did I mention its not backwards wednesday?
I dont mean to flame but...
I'm in the EE field, specifically wireless/radio communications.
The calculation for path loss is:
Loss dB = 32.44 + 20 log (dist in km) + 20 log (freq in MHz)
Lets take absolute optimal conditions..proxima centauri is roughly 4 light years away. This is roughly 3.78x10^13 km away. One of the most common frequencies monitored is the "hydrogen line" (1420.40575 MHz) since this is the resonant frequency of hydrogen and is more likely to be used by aliens since we'd most likely be looking there.
So, lets fill in the equation:
32.44+ 20log(3.78x10^13)+20log(1420.41)= 367.038 db of loss...
So lets say they are transmitting with a million watts(90dBm), and there is a 60db dish on both ends(huuge dish)...This gives us a receive level of -157.038dBm. This is a good bit below what any normal radio will receive at. The noise floor is certainly higher than this. Now keep in mind this is the very closest star, which I don't think even has any livable planets.
Our galaxy is 70-100 thousand light years across and we are right near the edge. So if you take a star not even close to that distance, say 500 light years (still somewhat close on a galactic scale) then the calculations work out to a receive signal of -198dBm. The equipment doesn't exist to pick the signal out of the noise at levels like that.
God forbid trying to pick the signal out of another galaxy, the nearest being Andromeda. some 2.5 million light years away. Giving Rx signal levels of ~ -273dBm. Safe to say the noise floor is MUCH MUCH higher than this.
I think SETI is a hopeless pipe dream. That being said, I DO think there is intelligent life out there, probably in our galaxy. There are just too many stars with too many planets to think otherwise.
It's easier to fight for one's principles than to live up to them.
"If you destroy currency you are removing it from circulation, which will cause prices to go down due to deflation.
If you truly want to waste money, you should buy something of value to others and destroy that thing."
Not at all. Either way, you remove value from the world. Whether in the form of a physical object of a particular value, or in the form of cash (a physical representation of abstract value), your destructive act has the same effect on the wider economy. Which is to say, not much unless it's an awful lot of money - value is constantly being created at a fantastic rate.
As far as whether money spent on SETI is "wasted", the point is not whether any good thing (like feeding the builders kids) comes out of it. The point is whether *more* good things would come out of spending that money on some other thing. That same builder could get paid, and feed his kids, building something in support of some more worthy cause. Is there a more worthy cause? Well, I think so, but it isn't my money.
"Research is almost always valuable, even if it turns up nothing."
For one thing quite a bit of research is utter garbage that neither proves nor disproves anything except that a particular researcher can't set up a good experiment; a fact of rather small value.
But more generally, there are always far more interesting research questions than we (as a society) can afford to pursue. That a particular program will learn "something" is too low a bar to decide which ones are worthwhile.
It is only reasonable to estimate SETI's chance of finding something, and the usefulness of that find, multiply the two together, and ask how much it's worth to spend on it. The answer obviously depends on your estimates. Mine come out to not very much.
"If we find no sign of extraterrestrial intelligence in our search we will know more than we did before about the abundance or scarcity of intelligence in our galaxy."
No, we won't. We have no way to judge the accuracy of our search technique.