There are new telescopes in operation

What telescopes? The paper I linked suggests only JWST-class and E-ELT-class telescopes can do the job.

and better ones coming

Yes, but they will come in 8 years. Arecibo is available right now.

Earth has had life for about 3.6 billion years but the first radio transmission was only 160 years ago. If I were a betting man my money is on the microbes.

It's not a matter of how long we are showing our presence to ET, but a matter of what we can detect from ET. Right now we can detect only ET messages, not biomarkers[1].

Apart from that, we aren't really sure about what biomarkers are relevant for alien life, we are using terrestrial biomarkers in the hope they also signal life outside Earth. For example, we are using ozone and oxygen as biomarkers, but Earth didn't have any of them until 2 billion years after the origin of life. Another biomarker is methane, but it's abundant in Titan and possibly of non-biological origin.

In his talk yesterday Eric showed a sky map with a lot of interesting astropulse data, some of which was seen more than once, so results are happeneing. Unfortunately for the impatient astronomy often takes decades or more.

Let's hope he will publish a more detailed explanation soon. I wan't to know what kind of signals have been found.

[1] Actually, some biomarkers have been detected in hot Jupiters and hot Neptunes, but we don't expect they host life, and only one or two biomarkers have been detected for each planet, not enough to confirm life. OTOH, to detect biomarkers in terrestrial planets on the habitable zone, we need JWST and E-ELT. Hot Jupiters and hot Neptunes aren't in the habitable zone, so, if they harbor life, it isn't life as we know it, so terrestrial biomarkers are pointless.

[1] Actually, some biomarkers have been detected in hot Jupiters and hot Neptunes, but we don't expect they host life, and only one or two biomarkers have been detected for each planet, not enough to confirm life. OTOH, to detect biomarkers in terrestrial planets on the habitable zone, we need JWST and E-ELT. Hot Jupiters and hot Neptunes aren't in the habitable zone, so, if they harbor life, it isn't life as we know it, so terrestrial biomarkers are pointless.

I would not conceed that but I would agree that other biomarkers are possible.

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We have to assume that ETI (extra terrestrial INTELLIGENCE) wants us to find them and therefore they will be broadcasting on the simplest form of long range communication. The other very remote possibility is that we might intercept some form of private signal not intended for us which could be some other exotic form. But that would mean that the earth is sitting on direct line between two alien worlds or ships. I seriously doubt that type of discovery will ever be made.

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Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.

I would not conceed that but I would agree that other biomarkers are possible.

Do you think that if, say, oxygen is detected in a hot Jupiter, it can be produced by plants, in a 2000 K atmosphere?

I would not conceed that but I would agree that other biomarkers are possible.

Do you think that if, say, oxygen is detected in a hot Jupiter, it can be produced by plants, in a 2000 K atmosphere?

Not at all, but metane in a cooler planet might be a biomarker. I'm just saying look for as many as possible.

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Not at all, but metane in a cooler planet might be a biomarker. I'm just saying look for as many as possible.

Cows don't have radios but they produce massive amounts of gas.

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Bacteria in the soil of swamps, lakes and seas produce more methane than cows :P

I don't think that single biomarkers can be signs of life. The important thing is the chemical equilibrium of the whole atmosphere. If it's far away from equilibrium and you can't explain why it is so, then probably it's produced by life.

Discussion of whether the signs of basic life can be detected on exo-planets many light years away is an interesting topic but not pertinent to finding signals from intelligent beings which is what the seti project is looking for.

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Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.

Discussion of whether the signs of basic life can be detected on exo-planets many light years away is an interesting topic but not pertinent to finding signals from intelligent beings which is what the seti project is looking for.

If I was going to attempt to tune in to Klingon soap operas I would look where Klingons are likely to be. First we find a planet in the "goldilocks zone", then we sniff for Klingon gas, then we watch Star Trek as filmed from a "bird of pray".

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I don't think that single biomarkers can be signs of life. The important thing is the chemical equilibrium of the whole atmosphere. If it's far away from equilibrium and you can't explain why it is so, then probably it's produced by life.

maybe you are interrested in a quote i found in a book:

The idea is that gas byproducts from metabolic redox reactions can accumulate in the atmosphere and would be recognized as biosignauters because abiotic processes are unlikly to create a redox disequilibrium. indeed earth's atmosphere has oxygen (a highly oxidized species) and methane (a highly reduced spcies) several orders of magnitude out of the thermochmical redox equilibrium.

In practice it could be difficult to detect redox disequilibrium molecular featurs. The earth as an exoplanet, for example, has a relatively prominet oxygen absorption feature at 0,76um, whereas methane at presentday levels of 1,6 ppm has only extremly weak spectral features. During early earth CH4 may have been present at much higher levels (1000 ppm or even 1%), as possibly produced by widespread methanogen bacteria (Haqq-Misara et. al 2008). Such high CH4 concentrations would be easier to detect, but since the earth was not oxygenatd during erly times the O2-CH4 redox dissequilibrium would not be detectable concurrently (des marias et al. 2002)

I have a colleague at work who asks me the same question every day. Have you guys found an alien yet Julie? And every time my answer is, ask me that again in 20 years Tom:))

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rOZZ
Music
Pictures

Carlo Rubbia says he found aliens in the Italian Senate, where he was nominated for life by President Napolitano.I imagine he feels like a fish out of water.
Tullio

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maybe you are interrested in a quote i found in a book:

The idea is that gas byproducts from metabolic redox reactions can accumulate in the atmosphere and would be recognized as biosignauters because abiotic processes are unlikly to create a redox disequilibrium. indeed earth's atmosphere has oxygen (a highly oxidized species) and methane (a highly reduced spcies) several orders of magnitude out of the thermochmical redox equilibrium.

In practice it could be difficult to detect redox disequilibrium molecular featurs. The earth as an exoplanet, for example, has a relatively prominet oxygen absorption feature at 0,76um, whereas methane at presentday levels of 1,6 ppm has only extremly weak spectral features. During early earth CH4 may have been present at much higher levels (1000 ppm or even 1%), as possibly produced by widespread methanogen bacteria (Haqq-Misara et. al 2008). Such high CH4 concentrations would be easier to detect, but since the earth was not oxygenatd during erly times the O2-CH4 redox dissequilibrium would not be detectable concurrently (des marias et al. 2002)

Yeah, that's it.