Jodie Foster’s character in the Hollywood blockbuster ‘Contact’ was inspired by you. Are the two of you alike?
?
How did you get involved in founding the SETI Institute?
I worked on one of the first minicomputers, known as the PDP-8/S, during my Master’s programme. It actually fit on a desk, and I learned how to programme it. Years later, when I was leaving university, Stu Bowyer asked me to join his team – because I could programme the old computer! (Charles Stuart Bowyer was the head of SERENDIP, an early attempt to use radio telescopes in the search for extraterrestrial intelligence.)
He gave me a copy of the Project Cyclops report. It was about the technological and financial challenges mankind would face if we were to attempt largescale interstellar communication. I read it from cover to cover, not because of the technical aspects of telescopes – the frequency, bandwidth, etc. – but because I realised something. For millennia, we have been trying to answer the question “Are we alone?” by asking priests and philosophers. But now – for the first time in history – mankind has been given tools that actually allow us to find the answer ourselves.
This was when I realised that if we ever found a signal that was provably from an alien civilisation, it would completely change our perception of ourselves and our place in the universe. So I was hooked! And in 1984, I co-founded SETI – the Search for Extraterrestrial Intelligence Institute – which explores the possibility of life in the universe.
It is true that Jodie Foster’s character, Ellie Arroway, in the film ‘Contact’ is based on me and my work.
In 1985, I had met Carl Sagan (famous astronomer and proponent of the idea of searching for life in the universe), who invited me to dinner at his home near Cornell University. He was working on a fiction book, and I later learned that one of the characters was based on me – a woman scientist who, like me, searches for life in space.
So the film had many similarities with my life. Ellie Arroway, played by Jodie Foster, and I had both lost our parents at an early age, and struggled with being women in a male-dominated world.
The film conveyed the essence of SETI’s work – but it also involved scientific errors that annoyed me a little. A potential signal from an extraterrestrial civilisation would not be as immediately clear and understandable as it is in the film (in the movie, the message consists of our own TV and radio broadcasts being sent back to Earth by an alien civilisation). In reality, a signal from space would likely require significant analysis and verification to ensure that it is indeed extraterrestrial in origin, and not just noise or interference.
But overall, the film was a positive experience.
We have no evidence of life yet. Has research progressed in a way that makes you confident that we will find it?
The fact that we have not found life out there yet does not mean it does not exist. The universe is huge, and we have not looked very hard until now – in fact, we have barely started searching.
And in recent times, we have witnessed two landmark breakthroughs. The first is the discovery of
“I realised that if we ever found a signal that was provably from another civilisation, it would completely change our entire perception of ourselves and our place in the universe.” JILL TARTER on why she co-founded the SETI Institute
exoplanets. When we started looking, we didn’t know of any planets other than those found in our own Solar System. And back then, the big question was whether other stars had planets.
Now we know that the universe includes more exoplanets than stars: each star has at least one planet on average, making it more reasonable to consider the possibility of life on some of these planets. NASA’s Kepler space telescope has discovered thousands, many of which are in their star’s ‘habitable zone’, where conditions could be right for life.
In addition, we have also found places in our own Solar System – such as Mars and some of the outer Solar System’s ice moons – that could involve the right conditions for life.
The second discovery is extremophiles: life forms on Earth that can survive very hostile conditions. Organisms exist near boiling hot and toxic ‘black smokers’ in the deep sea; these manage to survive with only one particle of light every half hour.
In other words, a planet does not have to be well-tempered and have exactly the right pressure and pH value for life to thrive.
Of course organisms that exist under such conditions may not be able to build radio telescopes. But they are alive. And that expands the areas out there that might be able to support life.
Has SETI changed the way the institute looks and listens for life?
SETI ‘listens’ for life aided by radio telescopes. In the early days, we focused on the hydrogen band or ‘21cm line’, the radio frequency where neutral hydrogen emits or absorbs energy. This frequency [around 1420MHz] was chosen because hydrogen is the most common element in the universe, so it seemed a logical place for an alien civilisation to send signals.
Since then, we have expanded our search to include more frequency bands. Modern radio telescopes can be set to ‘listen’ over a very wide range of frequencies, and sophisticated algorithms can analyse data from different frequencies faster and more efficiently than before. When it comes to systematic searches I have calculated that we can now do 1014 times [100,000 billion times] better compared to what we started with.
We do not know what alien civilisations look like. How do we know what to listen or look for?
Correct. We do not know how alien civilisations will manifest themselves. And so we basically do not know who and what to look for.
We also do not know how long a civilisation will last – whether it will survive long enough for us to make contact. After all, if mankind were to perish tomorrow, we would just disappear into the darkness without a trace! And if that is the case – if civilisa
In 1961, astrophysicist Frank Drake devised an equation bringing together all the variables that need to be known to estimate the number of intelligent civilisations in our galaxy. Scientists can give good guesses regarding the first variables, but the last four are highly uncertain.