H. Zaun: Now it looks like that the planet hunters did find several habitable Earth-like-planets candidates!

Tarter: The experts predict that less than 10 to 20 percent of the Kepler exoplanet candidates will turn out to be false positives. So the preliminary catalog of potentially habitable world from the Kepler data release is mostly correct. There is still a lot of work to do but potentially habitable worlds are numerous. There are more data that have not yet been released. So we know that there is good reason to expect that most of these candidates will in fact turn into verified planets when there are enough ground based observations available to conduct the follow-up observations. And of course there will be many more observations to come. But to find an Earth-like planet around a Sun-like Star at a distance of about one Astronomical Unit (AU) requires three transits, and three years – that cannot be achieved, not yet.

H. Zaun: Where do you see the most essential paradigm shift in our field?

Tarter: I see two paradigm shifts. First the new exoplanet worlds I have talked about; since 1995 we know that they are real and not just a good theory. And next: extremophiles. Throughout my career I have been confronted with an amazing explosion of newly discovered, exotic, well-adapted life forms that can survive under extreme conditions nobody had previously imagined. When I was a student I learned the canonical axiom that life needs sunlight. If it is freezing or boiling it may not survive. But now what we are finding is blowing that all away! The latest extremophile appeared only a month ago – a monumental creature from hell. It is a millimeter in size and it lives down very deep in the Earth under extremely high temperatures and pressures.

H. Zaun: But extremophiles are not able to send radio or laser signals – they must reach a higher level ...

Tarter: (laughs) Yes, microbes cannot build transmitters, which is our current, pragmatic definition of intelligence. But it does mean that the real estate out there that could support habitable environments is not as confined as we once thought. And how would these possible extraterrestrial organisms end up being well suited to their extreme conditions through millions of years of evolution? The point is that it might be possible for evolution operating in different environments to produce telescopes and built transmitters like the ones we have – the manufactured technology, based upon physics, might be the same even if the biology is not.

H. Zaun: When will ATA start with new observations? How optimistic are you concerning this point?

Tarter: I am always optimistic. I hope it will happen soon.

H. Zaun: In the recent discussion about cosmological topics you find more religious tendencies like the intelligent design concept or creationism, respectively. In August 2006 the established scientific magazine SCIENCE reports that only 40 percent of the American population really believes in the concept of evolution!

Tarter: Isn't this disgusting? The apparent rise and believe in pseudoscience is very disturbing in our country. In our previous administration we had a faith-based-science. It was really absurd and not science at all. This is very scary for any country that wants to continue to advance.

H. Zaun: You are referring to Mr. George W. Bush

Tarter: Yes, certainly I am referring to him and to his whole administration. In the near, and not so distant, future we'll have huge challenges and we are supposed to solve a lot of technological problems in order to insure the survival of the human species on Earth. If we allow science to be mistaken for pseudoscience and if we allow our politicians to make decisions on the basis of nonsense, then we do not have a bright future.
I am always amazed when I talk to people to find how willing they are to believe absolutely absurd things, just because somebody told them. We have deniers of climate change and deniers of evolution despite the overwhelming preponderance of scientific facts.

H. Zaun: And deniers like dogmatic priests and preachers who have strong influences over the media ...

Tarter: Yes, that is very disconcerting, too. It is not a good way to run a country, and it is not a good way to sustain as an intelligent population. Like it or not, the universe is as it is, independent of what you may choose to believe.

H. Zaun: What is your personal opinion about scientists who practice Active SETI like the Russian Radio Astronomer Alexander Zaitsev.

Tarter: We are children. We are an emerging technology in very old galaxy. We do not know whether there are other technologies out there. If there are – we know they must be older. I think what we need to do is recognize the asymmetry of our situation. If 'they' exist, they will be older. If they are older it is statistically unlikely that our first contact will also be their first contact. They have done this before for sure. They know how it works. As the youngest kids on the block, we should listen first and learn. When we ourselves have grown old, then we can take on a harder job of transmitting with the fair assumption that perhaps we are the first. I do not think that we should transmit until we have expended an amount of effort that is required to draw the incredible conclusion of our primacy. If we do inevitably get to be an old civilization, if we can manage our population, if we can use technology to stabilize our environment and search diligently for evidence of someone else and do find nothing – then we should start to transmit. And in that case we may have a reason to start discussions about the next question: Who is going to speak for Earth?

H. Zaun: Do you think the minds of the authorities will be changed when we got contact to another civilization?

Tarter: Well, we have held meetings and asked this question of diplomats, religious leaders, social scientists, media specialists, and other authorities. The best they can tell us is that the world will react to the announcement of the detection of an ETI signal in terms of whatever political and believe systems are ruling in that time. The specific thing I am worried about is whether the source might have a very high or a very low declination, so that there would be an intrinsic geopolitically, north-south, have not tension. In this case some countries will not get access to a territory that could in fact detect a signal. I think that could be a problem unless it is immediately made clear that we will form a global organization to share the information with everyone.

H. Zaun: Did you know that in 1977 two scientists used the German Radio Telescope in Effelsberg and made a short SETI-observation lasting only two hours?

Tarter: Really, they did? I didn't know this. I was there in 1981 and I proposed to do an experiment with one of the relatively local VLBI tape recorders, the Mark 1 at Jodrell Bank in England. At the time there were blank hours on observing schedule of that telescope. Only a few people really used it and there was time between their observing programs. I just said: "I got targets all over the sky and I want to use the Mark 1 and I will observe when no one else has been awarded time on the telescope. My proposal was turned down at first. And then the director of the Max Planck Institute for Radio Astronomy (MPIfR), Peter Mezger, convinced the time allocation committee with the statement: "Do you really want to miss out on the biggest discovery of mankind?" (laughs) And he forced it through. So I was permitted to do it – unfortunately, I couldn't pull it off because the Mark 1 recorder that I had hoped to use could not be made operational. So actually I was never to do the experiment.