Cellular Phone Spectra and Earth's SETI Invisibility

astrobio writes: "How long will the Earth's technology be detectable to other worlds? From an article today by the Chairman of the SETI Institute: 'Not long, with shared transmission spectra. To transmit ever-increasing amounts of information, portions of the spectrum must be shared. This is only possible if signal strengths are reduced so that transmissions on the same frequency do not interfere with one another. The textbook example of this paradigm is the cellular phone system. This signal reduction means we are well on our way to becoming invisible.'"

Comments

Good.

[Violet Null]

Maybe now the three-eyed, ten-tongued aliens of Vega will be able to get some rest once we turn the noise down.

Bad intergalactic neighbors, that's what we are.

This is not a new theory

[eclectric]

SETI researchers have known this for a good while now. As we move from broadcast television and radio to digital formats, we will essentially be reducing and eventually completely shutting off runaway transmissions out into the cosmos. This is actually included in probability calculations in the success of SETI: you only have about 200 years in a given civilization in which to find them through their leftover radiation... after that time frame, there are certain signals (radio telescopes, for instance) that are detectable, but which don't travel in every direction.

One of the goals/projects of SETI is to keep transmitting data that appears to be from intelligent creatures... Prime numbers in binary is one proposed method. A simple SOS is even possible... anything that would look nonrandom.

This may be a Good Thing

[rpjs]

Because do we really want to let the universe know we're here? Contact with a more advanced civilisation might have unfortunate repercussions for us - look at the impact contact with the West had on so many indigenous cultures during the ages of exploration and imperialism.

And that's just assuming the ETs are benevolent and simply can't help having the effect on us that we have on a newly contacted tribe in the Amazon. What if the ETs are paranoid about competitor intelligences arising and have a policy of wiping out any new civilisation that pops its head up over the electro-magnetic parapet? That's one of the more pessimistic explanations for the Fermi Paradox.

Re:This may be a Good Thing

[whovian]

On the other hand, what if a civilization gets the idea of "aliens" for the first time by discovering patterned interstellar radio signals? It's an involuntary violation of the Prime Directive on our part. In the big scheme of the universe (whatever that may be) I don't think this is so serious.

On the other hand, that civiliation too would probably get sued under DMCA :P

Not True

[Perdo]

I thought of this years ago. Then realized I was wrong. How much power does your local AM radio station put out? 50,000 watts. Will the ammount of power required to broadcast to three states ever drop? Nope. How many 50,000 watt radio stations are there in the US alone? Over 8000.

Will XM sattelite radio change that? Has linux been able to break Microsoft's monopoly?

Re:A limited form of invisibility

[dzym]

There is no reason expect that oxygen is the basis for all life in the universe. The scientific community has become increasingly aware of small bacteria-sized creatures currently termed archaea. These creatures do not depend on photosynthesis for their nutrition but instead rely on varying and diverse elements (including some of the "heavy" ones) and presumably also do not require the existence of massive amounts of oxygen to survive/thrive.

Bottom line: don't assume that just because humans require oxygen to survive, that any other alien species must also, and that they would necessarily also search for oxygenated worlds.