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SETI Project Scientist Discusses Prospects
An anonymous reader writes "Today Astrobiology Magazine interviewed SETI@home Project Scientist, Dan Wertheimer, about subjects including the first detailed 'best of SETI' candidate reobservations for repeating telescope acquisition on the most promising 166 star candidates. Their policy is not to release precise sky coordinates on the best ones yet (so far a signal called SHGb11+15a), with this type of Gaussian signal shape. The candidates number some 400 million Gaussians and 5.7 billion spikes."
They do.
here.
Click on each of the signals.
Iraq: war to save the U
Try upwards of 25%! On my 1.6GHz Win XP machine with screen saver client it would take approx. 20 hours for one WU. With command line that number is reduced to 4 hours. I haven't tested a pure Linux command line yet (no X server running).
that's not SHGb11+15a...
that's the sound of the signal from Contact.
Spooked me a little before I realised what it was, though.
Yes, it's a real radio telescope - they're pretty simple beasts really. Big dish, tuned receiver at the right frequency (or a frequency-converter, and a normal radio receiver), and a computer at the other end.
:-) external receiver tuned to the Water Hole frequencies (the gap between the OH line and the H2 line in the radio spectrum, at around 1420 MHz - pretty typical for radio astronomy, it's a relatively quiet part of the spectrum.
I use a WinRadio (despite the name, it's a universal box
Simon
Physicists get Hadrons!
A "pea" travelling at 90% of the speed of light contains a lot of kinetic energy. Say, 0.01 grams for the pea at 2.7e8 m/s. That works out to 7.3e11 J. That is about the same energy as exploding 175 tons of TNT per pea.
Set aside the issue of engineering the "peashooter" to fire them, you are talking about throwing some potentially destructive material at a neighboring star system. Firing them continuously looks like you intentially want to hit something. I think this might be a bad idea from a "just saying hello" viewpoint.
The improvement in performance over commandline is insane! Very little is spent on display output and this cannot be understate. I remeber once having to stuff a database with testing information -- some random numbers and strings. 1 million records on a machine twice my speed took almost a day (yes, it was access 97). It was using printf("%d\r",count); after every iteration. When I did the same thing, I did it with only printf every 10k iterations. It completed in just under 3 hours!
What SETI is looking for is actually power spikes. They are looking for places where the signal to noise ratio is obviously great (i.e. a "spike" above background noise), and hence, a signal is "detected." Once these interesting signals are detected however, it is another thing entirely to prove they are intelligent. Pulsars at first sound a lot like 101010101010. But no one thinks they're from an alien race (at least not yet ;).
It's in a box at 11h RA, +15 Dec.
No.
You can't copyright something you didn't write. Not counting works for hire and such -- but if they're claiming that they have aliens in far away galaxies working for them, they've got worse problems than copyright infringement.
Your argument are full of crap.
It's quite easy, even with a transmition over multiple frequencies, to detect that you have an artficial signal at frequency X. You may have are really hard time deconding it, but the transmition will still be very easy to detect.
When you yak on your cell phone, I may have a difficult time to capture and decrypt everything (especially if I have no prior knowledge on how the tramsition is done) but I will have no trouble locating you because of all the carrier signal you emit that don't look like any natural phenonema.
SETI is not trying to decrypt any signal, they are just trying to find if some signal appear artificial.
You really have a bad understanding of what SETI is looking for.
In fact, you don't even need a dish. The first radio telescopes were just dipoles. You can google around and find tons of descriptions of how to build radio telescopes on the cheap. It's particularly easy now with computers interfaced to radios.
That's a false assumption you've made. SETI admits that it has very little chance of detecting a civilization like our own - one that is just haplessly sending out signals - unless that civilization was very very close by. SETI is looking for more advanced civilizations that intentionally make their presence known by intentionally transmitting signals in ways that have been purposefully selected to be obviously non-natural. That's why SETI checks frequencies like pi*H and the space between OH and H2.
So, you're right. There's probably little chance that an alien civilization is using radio in a way we can detect. They are probably using fiberoptic cables for most traffic and transmissions that are so well compressed they are indistinguishable from noise for the rest. If they have colonies the communications between them are probably so highly directional we'll never pick them up. But maybe they went through the same process of searching that we are going through. And maybe, when they didn't hear anything, they decided to announce their presence. That's what SETI is looking for. OK?
None of the known extrasolar planets are supposed to be particularly good candidates for life, though that Vega case maybe indicates a solar system a little like ours, with rocky planets in the interior orbits... or that's the speculation.
We've still got a ways to go in refining our way of just looking for the things. To narrow any search based on them would be premature.
"Fundamentalism" isn't about divine morality. It's about human authority.
Any compression advanced enough is indistinguishable from noise. That might be a difficult task then.
-Adam
#!/bin/csh cat $0
This is false, and a confusion of data from transmission. Compressed data does in fact look fairly random (in fact, the less random it looks, the poorer your compression is). However, the only way to get the random data is to decipher the transmission, which is bloody obvious and would stand out like a sore thumb. Assuming what you're saying is true, we'll receive signals we have no hope of deciphering, but they will not look natural by any means. The data is random, but the transmission that carries that random data will look quite unlike white noise or anything of the sort.
Look at it this way: if an ancient civilization had stopped chiseling plain text on stone tablets and started chiseling compressed data streams, we would look at the compressed data and have no hope of ever understanding the message. But we wouldn't look at the symbols chiselled on the rock and say, "I don't understand this message, it must be natural phenomenon."
If you broadcast compressed and encrypted data by radio, or heck, if your broadcast a stream of random bits, it's still every bit as obvious as the chiseled stone tablets. Your "small 'hearable' window" is in fact huge. We would be able to hear the transmissions just fine. We just won't understand what they're saying.
But at that point, we just send them an unencrypted, easy to understand signal, and wait for a response. (We might even get one before they get ours, as they may be doing the same thing we are and have already detected our untranslatable babble and want clarification...)
"Convictions are more dangerous enemies of truth than lies."
Universal box, but what do you use to gather and present your data? The digital suite that is sold seems to be only for windows.
Like most things worth having, a solution will eventually present itself, especially on Linux. There is a Linux, open source, solution in the form of Linradio. Enjoy.
Jumpstart the tartan drive.
I love tossing this one out. Go out and read a translated copy of the Dead Sea scrolls.
You want to know why the Catholic Church declared them heresy?
Because everything in the Old Testament is in them and more. Funny thing, they all outdate the Christian religion by a LONG time.
No it's not. We already have dozens, if not hundreds, of applications (like GPS) that reside below the background level of noise and require advanced processing to extract the information. It's a very simple concept; if no one knew the frequency or code of GPS, it would be virtually impossible to find the signal below the noise level. And that's a system that was invented 20 years ago.