Like looking for aliens? What puzzles and problems facing SETI


If the aliens are trying to talk to us (or if not trying), Jill Tarter will find them first. She established the Institute of search for extraterrestrial intelligence (SETI) in 1984 and headed its research center for many years. Inspired by her work, the Director made the film “Contact” (1997) with jodie foster in the lead role. Astrophysicist Maggie Turnbull, who currently works for the Governor of Wisconsin, joined Tarter in the late 90’s and is now associated with the SETI Institute. She’s working on a NASA telescope WFIRST, which will go into space in 2025.

These two scientists somewhat different approach to the search for extraterrestrial life. Tarter focused on finding evidence of the existence of advanced alien technology, while Turnbull is looking for biological signatures. Wired magazine talked with scientists at the festival in San Francisco. And although they are looking for a few different things, both believe in the essential idea: search for life beyond our planet can unite us.

In search of aliens: the SETI Institute and NASA

The properties, which can make the system potentially habitable, you are looking for in the first place?

Turnbull: first, durability. The brightest stars burn their fuel faster and they burn their hydrogen reserves and will swell to red giants before will appear on the planet. These stars are not in the target list. In addition, if the star does not contain any heavy metals, if we assume that the planets formed from the same material from which the star formed, are less likely to find in this system of the planet. So that the metal poverty, too bad.

In space exploration there is a kind of bifurcation between the search for biological signatures of life and the search for technological signatures. Can determine what it is?

Tarter: SETI is search for extraterrestrial intelligence, but we have no ideas about how to detect the mind directly. So we take the technology at hand and ask: “are There any technologies out there that change the environment so that we could detect this at interstellar distances?”. If we can find any technological hint, we would guess that at some point was reasonable and the technologists who created it.

On the planet dominated by bacteria. Microbial life is far more prolific than complex life, and probably will be in a different place. Perhaps we should be looking for microbes before we find complex life.

But now these areas are a little different?

Tarter: throughout history, we searched for signals in the electromagnetic spectrum. Was doing SETI. Recently, given the emergence of new ground-based telescopes, the construction of which we are engaged, and new space telescopes, whose construction we do, we wondered how to use them to find something that can only technology?

Signals still seem like a good idea, but it could be many other things that we find. The community of astrobiologists was schizophrenic for some time, and it was normal to look for microbes at the beginning of complex life. Then they said, “No, SETI is not for astrobiology”. But now we had again to reconsider this, as the astronomers prepare for the next ten-year review of all the details that we can take and put in priority. And the Committee of the National Academy of Sciences stares at the strategy of astrobiologists, and it is more prone to accept the idea that as thesignature and biosignature fall under the large umbrella of astrobiology observations.

What are your favorite examples of possible alien technology that could potentially be detected by our instruments?

Tarter: There is a fabulous star system or planetary system called Trappist-1. Seven planets revolve around tiny dwarf star. They are Packed very tightly, all orbits would be squeezed in the orbit of mercury, whether they are in our Solar system. Three of them are at a good distance from its star, so if they were atmosphere, they would be liquid water. Okay, now take these seven planets located at various distances from its star. And let’s say that when we have the opportunity to explore them, we know what they look like. They have the same temperature. They so and look identical. This is unlikely, given the whims of mother nature, but if any technological civilization will arise on one of these planets and decide that she needed more real estate, it is, in fact, can convert all planets in their system, to make them the same.

Maggie, tell us about the telescope you’re working on and what it can detect.

Turnbull: Now my the largest and most comprehensive project is the telescope WFIRST. (Closer to launch it will get more exciting name). But this means Wide Field Infrared Telescope. This Observatory mainly designed to work with the deep sky and look for dark energy and dark matter. Two of the most interesting topics in astrophysics… But even more interesting for the astrophysics of extrasolar planets and life. Thus, as a technology demonstration, we include the first born of the camera in space, to directly capture images of nearby planetary systems. It’s never been done before.

We plan to start with some planetary systems, the existence of which for sure. We found them at the gravitational pull that planets exert on their stars. We’ve never seen them directly, but make sure that they are there.

What will you look for?

Turnbull: Water in the atmosphere has very strong absorption capacity. Plants have a distinctive signature, because they are very dark. We think they are green because they reflect some green light. But for the most part the plants are very dark because all absorb light and use it as a source of energy for the construction of their bodies. And they also reflect in the infrared, and there are many theories about why. Perhaps this is the mechanism of cooling — and whatever the meaning, it really is seen. The vegetation is clearly visible and was signals that were broadcast in the form of reflected sunlight in the Universe for the last billion years. We could see it on the planet earth type.

Maggie, you work for the Governor of Wisconsin.

Turnbull: I almost forgot!

What is the role of the public in SETI research?

Tarter: Let’s ask the audience how many people launched the [email protected] on their computers. (Many raise their hands). She has been working for more than ten years, and I think that’s what develops distributed computing and citizen science together. SETI did not invent distributed computing. People used it to calculate Mersenne primes, but [email protected] they liked the fact that they can use their computers to analyze saved data in search of a signal.

If anyone finds a signal, what would it look like?

Tarter: the Computer will report on some of the discovered parameters. At the University of California at Berkeley, where they are processed, they will fall into a great filter along with your other messages and will go through the analysis of whether the signal came from one point in the sky and moves as do the stars. It then creates a list of candidates from 10, 20 or 100 signals, then sends a request to reserve time on the telescope to re-research each of these places.

To attract people to the SETI incredibly important for another reason: it gives us the opportunity to change the point of view of each. It’s like, to raise the mirror and say: “See you all there on the Ground, you’re all the same, if you compare with something else that might be out there somewhere”. And creating a global network to address and work on this issue, I think it would be well to address other problems that we have on the planet that have no relation to national borders, but which need to be addressed systematically.

The blurring of the distinction between us is the best it can do SETI. This is the reason why we want to involve the whole world.

Astronomers would tell you that there are hundreds of billions of galaxies, each containing hundreds of billions of stars or something like that. So, mathematically, statistically, there is a huge number of planets that support life. But there are also people who claim that life had to appear on Earth due to a specific chain of events and the possibility that it will happen again, infinitely small. Have you ever thought about what might have devoted my career to search for something you never find?

Turnbull: No. I like it when everything in the palm of your hand. There are really good arguments for both possible answers. And I think that as a scientist, you must feel with the two options simultaneously. It’s like a quantum state that has not yet collapsed, but which you can submit at the same time. “Can’t be that to happen again!” and “They must be everywhere!”.

I think we’re talking about the brightest scientific field on the planet. It is so multidisciplinary. There are so many different lines of evidence and requests which are of importance for the search of life.

Tarter: When I was a young scientist, Philip Morrison, one of the founders of SETI, told me: “Any topic in which the margins of error are exponents, so we do not know is the limits of the tens, hundreds or millions, is not a theoretical science, it is science that is making progress through observation”.

And if you say, “Okay. You need to look for electromagnetic signals”, now there are nine different variables that could describe such a signal. So, you have the nine-dimensional search space. Take this amount of space to search for and apply it relative to the earth’s oceans. How many we captured? When I was doing the calculations ten years ago, I counted about a Cup of water of all the oceans of the Earth, so much space we explored. Last week the students published a revision of this thesis and claim that now it looks like the tub or a small pool. Much remains to be done. We barely started the search, it may not even be electromagnetic signals — it could be something else.

In the movie “Contact” jodie foster’s character discovers an alien civilization. During the interview for admission to work in a visit to the aliens, asked her what would be her only question to them. What would I ask you?

Tarter: I should note my bias because I was present at that interview with Carl Sagan, and my question would be: “How did you do it? How did you manage to pass the stage of technological maturity in which we are on Earth, and become old, stable, technological civilization?”.

Turnbull: I would probably have asked: “How many, how many of us here?”

The Fermi paradox States that if there were so many inhabited planets, we would probably would have received some evidence of this now. But we have not received. Because, perhaps, they come in contact, because they want to destroy you. And Stephen Hawking said that the search for extraterrestrial intelligence is a bad idea, because if they do come, they colonizing us, like Columbus colonized the New world. What do you think about this?

Tarter: If you asked the question: “is There in the ocean fish?” and then conducted an experiment, scooping up a glass of water from the ocean, or found in the fish, I don’t think you would come to the conclusion that no fish there.

This is the Fermi paradox. We were just looking for enough to be able to tell if someone’s here. And Maggie stole my favorite argument against Hawking’s statements, which is that it is difficult to become old, long-lived technological civilization, not getting rid of aggression and thus becoming intelligent in the first place. So if they arrive, to be honest, I don’t think we should worry about.

What happens when you look at our Solar system, what kind of signatures and information you receive about our Solar system?

Tarter: We spent some time on a number of radar studies of Lagrangian points. Many have suggested that the asteroids might be a good place to host the artifact, so we’re going to visit them. This part of the search thesignature. We don’t know what might find, so just going to find out what is in the Lagrange points L4 and L5. What are these clouds Kordylevskogo?

Jill, can you tell the audience what I think behind the scenes of some mysterious signals.

Tarter: we in radio astronomy is a mystery — what is a fast radio bursts? We think at least 10,000 appears in the sky every day. They live a millisecond or less, and we don’t know what it is.

Maybe it’s just the wormhole open and close around the sky for transportation. This was my idea for a sequel to “Contact”. But these bursts is a real mystery and we’re trying to build tools for research.

If we compare with the space program, are there any things that you create and which find applications in other areas?

Tarter: Some of the algorithms that we use to detect signals in real time have applications in other areas. A long time ago we were looking for a certain type of transform — the radon transform — and it was a great way to detect microcalcification when screening for breast cancer and mammograms. He passed the first stage of the research. It turned out that it’s too expensive and not applicable on a commercial scale. But he finds patterns in the noise. There are many different applications of this capability. Now we hope that what comes out of industry and University systems, neural networks, will help us to sift through data without a specific sample to search for. We allow neural networks to tell us, is there anything else besides noise.

Neural networks find? Tell us in our chat in Telegram.