First Contact Within 20 Years: Shostak

Space Daily ^ | Mountain View CA (SPX) Jul 22, 2004

[ckilmer]

EXO WORLDS

First Contact Within 20 Years: Shostak

Will the 20s see ET roar onto center stage Mountain View CA (SPX) Jul 22, 2004 If Intelligent life exists elsewhere in our galaxy, advances in computer processing power and radio telescope technology will ensure we detect their transmissions within two decades. That's the bold prediction from a leading light at the Search for Extraterrestrial Intelligence Institute in Mountain View, California. Seth Shostak, the SETI Institute's senior astronomer, based his prediction on accepted assumptions about the likelihood of alien civilisations existing, combined with projected increases in computing power.

Shostak, whose calculations will be published in a forthcoming edition of the space science journal Acta Astronautica, first estimated the number of alien civilisations in our galaxy that might currently be broadcasting radio signals.

For this he used a formula created in 1961 by astronomer Frank Drake which factors in aspects such the number of stars with planets, how many of those planets might be expected to have life, and so on. Shostak came up with an estimate of between 10,000 and 1 million radio transmitters in the galaxy.

To find them will involve observing and inspecting radio emissions from most of the galaxy's 100 billion stars. The time necessary for this formidable task can be estimated from the capabilities of planned radio telescopes- such as SETI's 1-hectare Allen Telescope Array and the internationally run Square Kilometre Array- and expected increases in the power of the microchips that sift through radio signals from space.

Shostak assumed that computer processing power will continue to double every 18 months until 2015- as it has done for the past 40 years. From then on, he assumes a more conservative doubling time of 36 months as transistors get too small to scale down as easily as they have till now.

Within a generation, radio emissions from enough stars will be observed and analysed to find the first alien civilisation, Shostak estimates. But because they will probably be between 200 and 1000 light years away, sending a radio message back will take centuries.

Paul Shuch, executive director of the SETI League, a separate organisation in New Jersey, says Shostak's prediction ignores one important factor. "It is altogether reasonable to project the development of human technology, based upon past trends and planned investments," he says.

"But predicting the date, the decade or even the century of contact is another matter because the 'other end' of the communications link is completely out of our hands. It would be nice to think we know something about the existence, distribution, technology and motivation of our potential communications partners in space, but in fact, we don't."

Shostak admits that there are myriad uncertainties surrounding his prediction, but he defends the basis on which he made it. "I have made this prediction using the assumptions adopted by the SETI research community itself."

[this_ol_patriot]

I installed BOINC on my work computer this week. I still have been able to download any information for it to work on. Any suggestions?

I just did 3 small WU's this morning but I am empty now and have had no work available since 16:51 Eastern. What I do then is try to update manually a few times and if that doesn't retrieve any WU's I just let it be. I did have Predictor@Home sharing 50/50 with SETI@Home but that is down now too. Some say to run the old classic SETI when this happens, leave BOINC up and see if it tries to get more WU's but you may have to manually update to check for more work if BOINC runs at a lower priority.

As long as you have contacted the server as shown in the logs like such:

SETI@home - 2004-07-24 17:17:04 - Sending request to scheduler: http://setiboincdata.ssl.berkeley.edu/sah_cgi/cgi
SETI@home - 2004-07-24 17:17:08 - Scheduler RPC to http://setiboincdata.ssl.berkeley.edu/sah_cgi/cgi succeeded
SETI@home - 2004-07-24 17:17:08 - Message from server: No work available
SETI@home - 2004-07-24 17:17:08 - No work from project
SETI@home - 2004-07-24 17:17:08 - Deferring communication with project for 1 hours, 0 minutes, and 0 seconds
--- - 2004-07-24 17:23:20 - Fewer active results than CPUs; requesting more work
SETI@home - 2004-07-24 17:23:20 - Requesting 78704 seconds of work
SETI@home - 2004-07-24 17:23:20 - Sending request to scheduler: http://setiboincdata.ssl.berkeley.edu/sah_cgi/cgi
SETI@home - 2004-07-24 17:23:23 - Scheduler RPC to http://setiboincdata.ssl.berkeley.edu/sah_cgi/cgi succeeded
SETI@home - 2004-07-24 17:23:23 - Message from server: No work available

you did all you can. Like I said earlier they have a few growing pains. Also they only crunch each WU 3 times as compared to many, many times for the classis S@H, so each WU you do get will be of more importance but they'll run out quicker or so they say. You could try varying the cache size to see if that changes things.

[RadioAstronomer]

LOL! I should buy it!

[Professional Engineer]

That's the kind of data my status screen shows. Good to know. Thanks for the info.

I tried to install the regular 3.08 and had some issue, so figured what the heck and do BOINC. I'll try again on that machine.

[RadioAstronomer]

And RadioAstronomer - how many have currently joined the 'net' to link for the search, or what ever you all it?

This I have no idea. I am just one of many running SETI@Home

[RadioAstronomer]

Hi FRiend. How're you doing these days?

Doing well. :-) Thanks for the hi! Been awfully busy as of late though.

[tet68]

Of course the problem has always been, what if they find us first!

We have only been transmitting for little over a hundred years,103 to be exact so our signal hasn't gotten very far
but who knows where they might be listening from.

[RadioAstronomer]

What if radio waves are as lethal as gamma radiation to most life forms?

Radio waves and gamma are the very same thing. Just that gamma radiation is at a much higher frequency. Note: energy increases with frequency E=hv (Where h is Planck's constant and v is frequency).

Since radio waves do not have the energy that gamma has, I find it unlikely that a species would evolve with a zero tolerance to radio waves.

[longshadow]

"e" equals "haich nu" to you too placemarker

[ckilmer]

sci fi guys and computer people talk about an inflection point somewhere about 2039. they figure at that time if computers keep increasing their speed at current rates then they'll produce something sentient. and things will become unpredictable.

[RightWhale]

What if radio waves are as lethal as gamma radiation to most life forms?

A valid question. Radio waves are too long to interact with chemical bonds, but a form of life made of gas rather than fluids and DNA polymers might be disrupted by radio.

[boris]

"Could it be that Light and Gravity propogate at different speeds?"

No. GR tells us that the "couple" that you think would disrupt the Solar System by generating extra momentum for each planet is precisely cancelled out by gravity waves eminating from the N-body (or 2-body, if you consider only each planet and the Sun) system.

Also, my dictionary advises me not to take scientific advise from someone who cannot spell "propagate" correctly.

--Boris

[GOPJ]

It's odd no intelligent patterns have been found so far. Wasn't it assumed the Universe would be teeming with life?

[muir_redwoods]

It's been said (Arthur Clarke?) That the failure of contact is our failure of imagination. We are trapped looking for ourselves and the others are so sufficiently different that we do not (cannot?) imagine how to contact them.

Depressing

[Southack]

"GR tells us that the "couple" that you think would disrupt the Solar System by generating extra momentum for each planet is precisely cancelled out by gravity waves eminating from the N-body (or 2-body, if you consider only each planet and the Sun) system."

Except, I'm thinking of no such "couple."

What I'm thinking of instead is that our solar system itself is moving, in fact, it is moving at an angle roughly 60 degrees offset from our planets' orbital plane around the Sun. So in 8 minutes, our Sun has moved several thousand miles NorthWest. In that same time, the Earth has likewise moved several thousand miles NorthWest, as well as moved laterally some small distance around the Sun. In the meantime, the light from the Sun's previous position is just now reaching the Earth.

So where we see the Sun is where the Sun was located a little over 8 minutes ago.

But, our lateral revolving orbital plane has continued to track the Sun's NorthWest movement...we continue to orbit around the point of the Sun that we won't see until a future 8.3 minutes has passed.

Yet Gravity isn't psychic. It doesn't "know" where the Sun will be located in 8 minutes. It only knows where the Sun is located at this very moment.

And that's the point that we revolve around: where the Sun is now.

But we don't see where the Sun is now. We see where the Sun was 8.3 minutes ago...because it takes Light that long to make the trip between the Sun and Earth.

So how does Gravity see the present Sun, rather than the Sun that Light sees 8.3 minutes ago?

One potential answer is that Gravity is much, much faster than Light.

5 Legislative Days Left Until The AWB Expires

[js1138]

placemarker.

[ChicagoHebrew]

They might have life, but a water-based civilization would have a hell of a time becoming advanced for one reason: lack of fire!

[boris]

"What I'm thinking of instead is that our solar system itself is moving, in fact, it is moving at an angle roughly 60 degrees offset from our planets' orbital plane around the Sun. So in 8 minutes, our Sun has moved several thousand miles NorthWest. In that same time, the Earth has likewise moved several thousand miles NorthWest, as well as moved laterally some small distance around the Sun. In the meantime, the light from the Sun's previous position is just now reaching the Earth. So where we see the Sun is where the Sun was located a little over 8 minutes ago. But, our lateral revolving orbital plane has continued to track the Sun's NorthWest movement...we continue to orbit around the point of the Sun that we won't see until a future 8.3 minutes has passed."

You are thinking of a phenomenon similar to the "abberation of star light" which is called the "abberation of sunlight". The abberation of light is real because it travels at finite speed. It is responsible for the Poynting-Robeson effect, which causes a slight pressure which opposes the earth's orbital motion.

Applying the same (invalid) logic to gravity will tell you that there is an "inverse Poynting-Robeson" effect due to the "abberation of gravity", which will tend to accelerate the planets and eject them from the solar system in a very brief time (thousands of years).

The problem, as I said, is that GR shows that the acceleration of the "inverse Poynting-Robeson" effect is precisely cancelled out by emission of gravity waves, so that the planets really DO orbit the sun as if gravity travelled at infinite speed.

Do us all a favor and do some research on this topic, which has been beaten to death elsewhere. Correspond with Dr. Carlip as I did. Educate yourself. Please.

--Boris

[Southack]

"The problem, as I said, is that GR shows that the acceleration of the "inverse Poynting-Robeson" effect is precisely cancelled out by emission of gravity waves, so that the planets really DO orbit the sun as if gravity travelled at infinite speed."

Indeed, that's the appearance, and perhaps Gravity really is that fast (or nearly so). If Gravity is almost infinitely fast, then one would expect advanced alien civilizations to consider using it instead of electromagnetic waves for communication.

Of course, if the effect is merely one of appearance, then such may not be the case for alien civilizations at all.

I would like to point out, however, that *each* of your posts to me have included condescension, nitpicking, and often outright insults.

Yet in the end you came around to my original point about the appearance of the speed of Gravity.

Perhaps in the future either you'll be better behaved, or else I'll be less civil to you in return.

For this thread, I've given you a pass on your behavior. Don't count on such charity from me in the future.

5 Legislative Days Left Until The AWB Expires

[boris]

"I would like to point out, however, that *each* of your posts to me have included condescension, nitpicking, and often outright insults."

Richly deserved. I do not tolerate fools easily.

[Southack]

If our current level of science is wrong, and if gravity propagation is actually faster than radio waves, then advanced civilizations may not be using radio at all, except for a brief period early in their development. - Southack, Post #16

"...the planets really DO orbit the sun as if gravity travelled at infinite speed." - Boris, Post #137

My original observation was not a foolish one, and you came around to agreeing with it in the end.

5 Legislative Days Left Until The AWB Expires