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Posted

i just saw a t.v. show about finding a planet and how hard it is. I was wondering if the earth is just as hard to see. If there are any intelligent life out there they probably dont know where to look either. i was wondering if there is any kind of satellite or some technology we could put in orbit that would help earth be more noticible. like a lighthouse, something that would not occur naturally.

 

jason

Posted

If we built a large number of high wattage transmitters that broadcast in different frequencies, ET would have a chance of hearing the transmissions. This is actually exactly what we’ve been doing for decades with radio, television, military and many other signals we produce here on earth. This would either be luck or unlucky for us if ET shows up having followed Spongebob Squarepants to the source depending on ET’s intentions.

 

Also, some 30 years ago astronomers used Arecibo to transmit a very powerful message to a distinct group of stars in a globular cluster inhabiting our galaxy. As I recall the message had a picture of DNA and stick figures of people. Most likely ET will see this as a distress signal saying we need DNA or we will starve :)

 

- modest

Posted

I found this article rather interesting.

 

Time is the biggest factor really. By the time our messages reach intelligent life and the intelligent life responds, it could be hundreds of millions of years (conservatively). Signal degradation also seems to be an issue with broadcasting to distant parts of the universe.

 

I think SETI should continue indefinitely because there is that "more than any kind of lottery" chance that we'll get a sign(al). That sign would be profound enough to warrant SETI imho.

Still, I don't think we'll have much luck ever meeting E.T., even if we hear it's distant murmur, millions of years later.

Posted

i got this message back from nasa;

 

SEARCH FOR NANOSECOND OPTICAL PULSES FROM NEARBY SOLAR-TYPE STARS

 

Andrew W. Howard,1 Paul Horowitz,1 David T. Wilkinson,2, 3 Charles M. Coldwell,1 Edward J. Groth,2 Norm Jarosik,2

 

David W. Latham,4 Robert P. Stefanik,4 Alexander J. Willman, Jr.,5 Jonathan Wolff,1 and Joseph M. Zajac4

 

Receivved 2004 March 16; accepted 2004 June 11

 

ABSTRACT

 

With ‘‘Earth 2000’’ technology we could generate a directed laser pulse that outshines the broadband visible

 

light of the Sun by 4 orders of magnitude. This is a conservative lower bound for the technical capability of a

 

communicating civilization; optical interstellar communication is thus technically plausible. We have built a pair

 

of systems to detect nanosecond pulsed optical signals from a target list that includes some 13,000 Sun-like stars,

 

and we have made some 16,000 observations totaling nearly 2400 hr during five years of operation. A beam

 

splitter–fed pair of hybrid avalanche photodetectors at the 1.5 m Wyeth Telescope at the Harvard/Smithsonian

 

Oak Ridge Observatory (Agassiz Station) triggers on a coincident pulse pair, initiating measurement of pulse

 

width and intensity at subnanosecond resolution. An identical system at the 0.9 m Cassegrain at Princeton’s

 

Fitz-Randolph Observatory performs synchronized observations with 0.1 s event timing, permitting unambiguous

 

identification of even a solitary pulse. Among the 11,600 artifact-free observations at Harvard , the

 

distribution of 274 observed events shows no pattern of repetition, and is consistent with a model with uniform

 

event rate, independent of target. With one possible exception (HIP 107395), no valid event has been seen

 

simultaneously at the two observatories. We describe the search and candidate events and set limits on the

 

prevalence of civilizations transmitting intense optical pulses.

 

Subject headinggs: astrobiology — extraterrestrial intelligence — instrumentation: detectors —

Posted

I found an interesting article at New Scientist's website:

 

Alien astronomers could discern Earth's features

 

Aliens spying on us from another star system might be able to discern continents and oceans on our planet, using technology barely more advanced than our own.

 

In imaginary form, these inquisitive extraterrestrials have been helping astronomers work out how much detail the next generation of space telescopes could reveal on Earth-like planets orbiting other stars.

 

Alien astronomers could discern Earth's features - space - 21 December 2007 - New Scientist Space

Posted
i just saw a t.v. show about finding a planet and how hard it is. I was wondering if the earth is just as hard to see. If there are any intelligent life out there they probably dont know where to look either. i was wondering if there is any kind of satellite or some technology we could put in orbit that would help earth be more noticible. like a lighthouse, something that would not occur naturally.

 

jason

 

 

Yeah I dont think it is necessary any ET just two thousand years more advanced than us would know our planet is a living one but probably dont realise our planet has intelligent life on it just yet for reference just look at the terrestial planet finder project that was shelved by NASA that will happen in the next 50 years.

 

IMO any ET civ that was 10 to 20 thousand years more advanced than us would be interstellar and using technology we cant even imagine as yet.

 

they would probably know we have intelligent life on the planet but just arent interested in us probably a good thing too, IMO I think living planets are common with planets having intelligent species on them quite rare but still that leaves a lot of civs out there, even in our galaxy alone I expect there to be thousands at various stages of tech development but because of the vast distances involved will probably never meet or will take millions of years before they do meet.

 

Interesting to think about though isnt it.

 

Peace

:rolleyes:

Posted

I'll still stand by my initial premise that time is the biggest factor to consider.

Even if we picked up alien radio waves from Alpha Centauri (our closest star), then it would still take us 4.37 light years to get there. Traveling at 1/16 the speed of light (impossible by today's standards) we would reach there in about 70 years. That's the CLOSEST star system!!

 

So even if we do receive a signal from some distant star, we have little chance of actually making contact with them. By the time we got there, it'd be a whole different evolution at that point, or perhaps extinction.

Posted
I'll still stand by my initial premise that time is the biggest factor to consider.

Even if we picked up alien radio waves from Alpha Centauri (our closest star), then it would still take us 4.37 light years to get there. Traveling at 1/16 the speed of light (impossible by today's standards) we would reach there in about 70 years. That's the CLOSEST star system!!

 

So even if we do receive a signal from some distant star, we have little chance of actually making contact with them. By the time we got there, it'd be a whole different evolution at that point, or perhaps extinction.

 

I agree and it got me thinking about the exponential nature of life in relation to stellar exploration.

 

If an alien civilization sent 2 stellar cruisers off to the 2 nearest stars with natural resources one could expect the process to continue after the cruisers make a 'home' of their new star. They would send 2 new cruisers off and the process would continue exponentially.

 

There are about 200 billion stars in the milky way, so... 2^x = 2.0 x 10^9... where x is the number of 'steps' in time needed to visit every star in the galaxy. Here x = about 38. If it takes 1 million years to process a star system for resources and move on to the next star then a galaxy would be fully populated in 38 million years. That's not long by galactic standards.

 

Would it be logical to say there is no very-intelligent life in the milky way because they are not populating a majority of stars including our own? In other words, why assume E.T. is in one star system. Perhaps each galaxy has or will have one intelligent species inhabiting the entire galaxy.

 

- modesr

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