Breakthrough Listen project: Indian member harassed by calls about contact with aliens

Sujan Sengupta, an associate professor at Indian Institute of Astrophysics, Bengaluru, is a much harassed man nowadays - harassed by unsolicited callers. One wanted to know if the scientist has come in contact with an alien. Another reported that he had found something that could be an alien signal. "I am tired of these guys," says Sengupta.

The calls started on July 20, when Russian billionaire Yuri Milner announced the $100 million Breakthrough Listen project to look for extraterrestrial intelligence. The money was big, but so were the men Milner got to rub shoulders with: Stephen Hawking, the world's most famous theoretical physicist; Martin Reese, the British cosmologist after whom an asteroid is named; Geoffrey Marcy, the American astronomer who discovered 70 of the first 100 extra-solar planets man could find; and Pete Worden, former Nasa Ames Research Centre director. The only Indian in the Breakthrough Listen team is Sujan Sengupta.

"If you forget the calls," says the scientist who has been studying extra-solar planets and brown dwarfs, "I am quite excited." The search for extraterrestrial intelligence (SETI) dates back to the late 19th century when physicist Nikola Tesla suggested that humans could send electrical signals to Martians. But SETI got its name only in 1960 when American astrophysicist Frank Drake launched Project Ozma that used a 26m radio telescope to 'listen' to signals from outer space, some of which he thought could be from aliens. Breakthrough Listen will use the 100m telescope at the Green Bank Observatory, West Virginia, and the 64m telescope at Parkes Observatory in Australia for hundreds of hours, for ten years. It will also search for optical signals using the Automated Planet Finder of Lick Observatory in California.

Breakthrough Listen spells out its first two initiatives on its homepage. One: A complete survey of one million nearest stars, the plane and centre of our galaxy, and the 100 nearest galaxies. All data will be open to the public. Two: A $1million competition to design a message representing Earth and humanity that could potentially be understood by another civilization.



"It's a funny project because we are looking for something which we know nothing about," says Sengupta. "But then, there are 200 billion stars in our galaxy and there are some 200 billion galaxies in the visible universe, so there must be someone sending a signal from somewhere," says Sengupta.

How do we know if some signals the radio telescopes receive are from ET, when celestial objects continuously send out radio pulses? The thumb rule has been that if a set of signals is systematic and regular, without the sidereal characters associated with celestial bodies, it should be from an intelligent source. In 1967, Antony Hewish and Jocelyn Bell Burnell were excited when they recorded pulses separated by 1.33 seconds emanating from the same location in the sky. They named them LGM (little green men). Soon they turned out to be coming from a hitherto unknown celestial source. And Hewish went on to get the Nobel Prize in 1974 for aiding the discovery of pulsars.

Breakthrough Listen, however, is not all about listening, it will also send out some radio signals for ET to detect. Astrophysicists remain sharply divided on the origin of the universe - many hailing Hawking's Big Bang theory, and some others like Jayant Narlikar who flay it as pseudoscience - but everyone agrees on the possibility of existence of extraterrestrial intelligent life.

Hawking, who has been cautioning against sending radio signals since advanced extraterrestrials could ruin us, seems to have partially come around with the Breakthrough project. Hawking, who said in 2010 that aliens would be "looking to conquer and colonize whatever planets they could reach", has now said: "We are alive. We are intelligent. We must know."

To know, an array of radio telescopes at Tata Institute of Fundamental Research in Pune has been tuning in for alien signals, so far with no luck. However, Jayant Narlikar, founder of Inter-University Centre for Astronomy and Astrophysics in Pune, went a different way. His team sent out balloons from Hyderabad in 2001, and collected microbes from an altitude of 41km, in sterilized cans. They didn't find much more than a few varieties which are unusually resistant to UV radiation. The team tried the experiment again with improved methods in 2005, and got three types of microbes which were so far not seen on Earth. "Did they rise from Earth or were they falling to Earth?" says Narlikar. "And we don't have the answer yet." For this, he is planning another round of experiments including isotope analysis of the microbes.

The two missions are looking for different ways to answer the same question - is there life beyond Earth? Breakthrough, though, is looking at intelligent life. Former Indian Space Research Organization (Isro) chairman U R Rao, who was part of Narlikar's experiments, says listening is the best thing to do now. "As we send out radio signals for ETs, they must be sending out signals to us. We are asking each other physicist Enrico Fermi's famous question: Where's everybody? One day we hope to find a watering hole where buffaloes from Earth and those from another planet can chill out," says Rao.

But, returning to Hawking's fear, what could happen when we finally communicate with the aliens? A radio signal from a probable intelligent civilization takes light years to reach Earth, which means that civilization is light years ahead of us in terms of prowess. If they decide to check out the source of our signals and set out on their spaceships earthwards, what would they do? Holler 'what on earth are you doing here?' or croon 'honey, I'm home'? Nobody knows.