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Beyond Contact: a Guide to SETI
Some readers may recall what Stephen Hawking said about his book, A Brief History of Time:
"Someone told me that each equation I included in the book would halve the sales. I therefore resolved not to have any equations at all. In the end, however, I did put in one famous equation, E=mc2. I hope that this will not scare off half my potential readers."
Hawking was facing the same challenge as Brian McConnell faces in this book. Both are trying to turn advanced knowledge of their field of endeavour (which requires heavy math, heavy astronomy, heavy physics, heavy programming, and so forth) into a work which can be comprehended by lesser beings. McConnell has taken a different path than Hawking - his book has plenty of advanced equations, diagrams, and concepts. McConnell does a reasonable (and often very good) job at trying to bring readers up to speed when he thinks he's going to go over their heads, but it is still not a book for the faint of heart or mathematically-challenged. There are enough equations in the book to bring its readership down to (.5)n -- oh, roughly zero, give or take.
In any case, it's a good book, but technical. You were warned.
The first couple of chapters cover the history of searching for extraterrestrial life, "are we alone?", the nature of intelligence, and similar areas. Drake's Equation is the famous set of fudge-factors that would tell us whether we were likely to find other life forms, if only we knew what the values of the variables were:
N = R * fs * fp * ne * fl * fi * fc * L
Fill in values for all of those and you'll be famous forever. But what it means, as our knowledge stands now, is that we have no clue at all whether there is likely to be life out there or not. Comforting, isn't it?
The next several chapters cover the technical aspects of communicating over interstellar distances. The electrical engineers in the audience will have a leg up here; everyone else has the opportunity to learn the basics of signal processing and the peculiarities specific to communication across galaxies. Pretty thorough and informative, without being overwhelming.
Finally, the latter half of the book covers the 64,000 lightyear question: what to say? How to communicate with an intelligence where you can't assume even the most basic things in common? Yes, yes, you've probably heard of the idea of starting with the periodic table or basic mathematics and working up. But that's sort of like a dot-com business plan:
- Establish Contact
- Send Periodic Chart
- ....
- Communicate!
McConnell fills in the "...." part, and it's obvious that a great amount of thought has been put into it. Pretty quickly McConnell is describing how to send entire self-executing programs (see Vernor Vinge's A Fire Upon the Deep).
This book is a bit of an oddity. If we're just talking about entertainment reading, it falls short - too technical. If I was grading it as a scientific work, again it would fall short - not technical enough. :) But as far as I know, this is the only work which tries to explain what SETI really is in terms that educated, reasonably bright laymen can understand, and as such, it does a fine job.
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3. Wait 40 more years
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-J
Alexis 'jeriqo' BRET
crunching? Missile ranges? Nuclear calculation?
A few sys admins at The Swedish Radio
where fired some time ago because they had seti@home running on some machines.
The management said that didn't know what seti@home acutely did.....and of course that it was a security threat....
Just my 0.02
Probably the single greatest challenge facing SETI-like projects is not the daunting task of acquiring and analysing the vaast ammounts of data, but the criticisms levelled at it by many politicians and scientists.
To date, most books on bioastronomy in general and seti in particular have been rather daunting and require a good grasp of not just physics and biology, but even philosophical issues such as anthropomorphsim and technical matters such as DSP; a popular book on the subject, such as this one, could go a long way to raising public knowledge of the subject past the "looking through telescopes for aliens" level.
"Alien Civilizations in a Nutshell" Then they could have put a cool animal on the cover. Now, what animal goes with SETI?
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fc is the fraction of intelligent species that develop the ability and desire to communicate with other civilizations : after the aliens realize the voice of the UN secretary general of the time on the Voyager probe recording was a fucking Nazi, probably 0.
Therefore, N=0.
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
There's little chance the current SETI program will find ET. The problem is that SETI has no dedicated, high-sensitivity telescopes. They simply can't afford it. The best they've been able to do is "piggyback" with other radio astronomy projects and listen in. /., we can thank Microsoft's Paul Allen for donating the $26 million to fund the Allen Telescope Array, to be built in California in the next five years (I think), which should alleviate this problem. It'll be a network of smaller telescope arrays programmed to act as a single, massive radio telescope.
And although this may be unpopular on
"Me Human, You Alien: How to Talk to an Extraterrestrial" by Jonathan Vos Post (c) 1996 by Emerald City Publishing an excerpt from a book entitled MAKING CONTACT: A SERIOUS HANDBOOK FOR LOCATING AND COMMUNICATING WITH EXTRATERRESTRIALS, edited by Bill Fawcett, July 1997, New York: William Morrow & Co. http://www.magicdragon.com/EmeraldCity/extraterres trials/alien.html
This has original ideas on how you, personally, should best prepare to communicate with ETs, including what to carry in your pockets. It also has the best review of Science Fiction approaches to the concept, as well as anthropology and linguistics.
N = R * fs * fp * ne * fl * fi * fc * L
R = the rate of formation of stars in the galaxy
fs = the fraction of stars that are suitable suns for planetary systems
fp = the fraction of those stars with planets (thought to be around 1/2)
ne = the number of "earths" per planetary system i.e., planets suitable for liquid water
fl = the fraction of those planets where life develops
fi = the fraction of planets with life where intelligence develops
fc = the fraction of those planets that achieve technology which releases detectable signals into space
L = the lifetime of such communicative civilizations
2. Let's be generous and say there is a one in a thousand shot of a star having planet capable of supporting life (right distance from the star so that it's between 250-350 K at the surface, enough atmospheric pressuse so that water can exist as a liquid, protected by massive outer planets against constant meteor bombardment, far above-average abundance of Oxygen, Sulphur, Nitrogen, and Phosphorous, etc, etc.) That puts the number of *potential* life supporting planets in the galaxy at 400 million.
3. Let's be very, very generous and estimate that life actually *does* form on one in every thousand potential life-supporting planets. Most molecular biologists will tell you that even the most basic life is so complex that the odds of it forming from inanimate matter are staggeringly small, and we should count ourselves lucky that it managed to happen once in the entire history of the Universe. But we'll be liberal and say one in a thousand. That puts the number of planets in the galaxy with any sort of life at 400 thousand.
4. There is no reason to assume that just because life exists, it will become intelligent and start using EM communications that we can receive. I don't know how you could put odds on something like that. Let's just go nuts and say that ALL planets with life eventually give rise to intelligent life. So 400 thousand planets out there in our own galaxy will have intelligent life at some point in their history.
5. Now, here's the depressing part. Our planet has been around for 4 billion years. We've been using EM waves to communicate for roughly 100 years. So, in the whole history of our planet, civilization has only been detectable for 0.0000025 *percent* of the time. Let's say your typical advanced civilization (using radio waves) can last 1000 years before nuking itself into oblivion, and your typical planet exists for 5 billion years. That would mean that out of the 400 thousand planets with life, chances are only 0.00002 percent of them, or 0.08 total, are broadcasting at the same time we are receiving.
Thus, even with the most wildly optimistic estimates, there is only an 8% chance that there is even one civilization out there that we can listen to, in the entire galaxy. Forget about there being one within 100, or even 1000 light years.
Of course, you could simply throw those numbers out, and believe in a God who likes to put intelligent life on planets all over the place. But that wouldn't be very scientific.
dinner: it's what's for beer
Fermi's objection to the existence of extraterrestrial civilizations goes something like this: It should take a spacefaring civilization about 1-10 million years to colonize a space the size of the galaxy, even without faster than light travel (the idea is exponential growth -- we send two colonies, then they send two colonies each, and so on). Since 10 million years is short with respect to the amount of time the galaxy has existed (10 billion years) and the amount of time that life has existed on Earth (4 billion years), there should be evidence of colonization everywhere, even if there is as few as one advanced civilization. So, where is everybody?
I'd like to know if the book discusses this. Many SETI researchers are approaching the conclusion that humanity is the most advanced form of life in our own galaxy, at least.
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I confess to not having read the book, but I've never seen any decimal used in proposed SETI communications (nor, I suspect, have you).
Most "number" transmissions I have seen have been unary (in other words, three pulses equals three). I know binary was used on the plaque in (ummm) Voyager, was it? but that wasn't a serious attempt to communicate with other species.
Mathematicians aren't stupid, and I promise you that they know perfectly well that aliens aren't likely to use base 10.
ZFS: because love is never having to say fsck
If you happen to be talking with someone via radio who has never seen a clock, try to explain to him what "clockwise" works. Maybe you would turn to the rising and falling of the sun and moon as a reference point, but if this person has never been outside or lives in a different solar system? Where is the common reference point?
How we know is more important than what we know.
If there are other lifeforms out there, what are the chances that they would be on the same technological level as us?
Even if they had something more advanced than radio waves (whatever that might be), certainly they would realize that RF is a cheap, simple, robust solution to certain problems -- such as, say, navigational beacons. Even on Earth, with GPS and other hi-tech navigational aids governing the waterways, we still use lighthouses to say "stay away" in the clearest possible language.
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Danny.
I have written over 900 book reviews
I remember a stand-up comedy routine where the guy said that in order to ensure that First Contact goes smoothly, all Earth citizens should carry chewing gum at all times, in case they are the first to meet ET. That way a friendly encounter is assured:
Alien: beep. beep.
Human: Want...some.....gum?
Liberal (adj.): Free from bigotry; open to progress; tolerant of others.
I just realized that hardcore seti geeks are so mad that if they personally actually met some aliens they would get really excited...
alien: how are you gentlemen! We are aliens!
seti geek: omg! fuck! real aliens!
alien: take us to your leader!
seti geek: do you have alien computers?
alien: indeed
seti geek: are they really advanced compared to ours ?
alien: indeed
seti geek: Do you mind if I run seti@home on them ?
graspee
Calculate your own values for the drake equation here
Scientists Decode the First Message From an Alien Civilization...
Simply send 6 x 10^50 atoms of hydrogen to the star system at the top of the list, cross off that star system, then put your star system at the bottom of the list and send it to 100 other star systems. Within one-tenth of a galactic rotation you will receive enough hydrogen to power your civilization until entropy reaches its maximum! IT REALLY WORKS!
M@
Krispy Cream is people