Are we alone in the universe? This question has haunted humans ever since they started gazing at stars. Today, the search for answers is backed by technology: radio telescopes and computers to scan the universe. However, any astronomical phenomenon which offers a hint of an answer to this question sparks off speculation. Last week, the focus was on the news that astronomers were picking up ‘strange signals’ from Ross 128, a red dwarf star 11 light years away. The signals were detected by researchers at the Arecibo Observatory in Puerto Rico on May 12. There was speculation that the signals were sent by aliens. The conclusion of the scientists, given below, however, was not widely reported.
Professor Abel Mendez, Director of the Planetary Habitability Laboratory at the University of Puerto Rico dubbed the signal as ‘Weird! Signal’, in the fashion of another signal dubbed as ‘Wow! Signal’ in 1997. The Ohio State Search for Extraterrestrial Intelligence (SETI) programme gained fame when Jerry Ehman, a project volunteer, noticed a strong signal received by the radio telescope. He scribbled “Wow!” in the margin of the printout. Dubbed the “Wow! Signal”, it is considered the best candidate for a radio signal from an artificial, extraterrestrial source so far, but it has not been detected again despite several searches. It also did not contain any message.
Since the Weird! Signal could not be explained, the team at Puerto Rico took more observations of Ross 128 and asked SETI groups to join in. Mendez wrote in his blog:
“After a careful analysis of the observations performed last Sunday from the Arecibo Observatory, together with SETI Berkeley from the Green Bank Telescope and the SETI Institute’s ATA, we are now confident about the source of the Weird! Signal. The best explanation is that the signals are transmissions from one or more geostationary satellites. This explains why the signals were within the satellite’s frequencies and only appeared and persisted in Ross 128; the star is close to the celestial equator where many geostationary satellites are placed.”
Mendez and his team were studying red dwarf stars. However, many scientists are busy searching the universe for signals from extraterrestrial life. According to Prof Jill Tarter, in 2012 it cost around “$2 million per year to keep SETI research going at the SETI Institute” and 10 times that to support “all kinds of SETI activity around the world.”
Millions of dollars have been spent on radio telescopes and scanning of the skies for more than 50 years, but till today, no significant signal has been recorded.
SETI attempts are still on. In 2015, Stephen Hawking and Russian billionaire Yuri Milner announced the Breakthrough Initiatives to expand SETI efforts. Breakthrough Listen is a $100 million programme of astronomical observations in search of evidence of intelligent life beyond Earth. A survey of the 1 million nearest stars and 100 nearest galaxies will be done and all data will be open to the public.
Scientists are divided over the existence of ETI. In November 2013, astronomers reported, based on Kepler space mission data, that there could be as many as 40 billion Earth-sized planets in the Milky Way Galaxy and the nearest planet in the habitable zone may be only 12
However, the Rare Earth Hypothesis by Peter Ward and Donald Brownlee, argues that planets with complex life, like Earth, are exceptionally rare.
Carl Sagan thought scientists should study the Unidentified Flying Objects (UFOs), today also known as Unexplained Aerial Phenomena (UAP), because there was widespread public interest in UFO reports. To argue that the Earth was being chosen for regular visitations, Sagan said, one would have to assume that the planet is unique.
And that assumption “goes exactly against the idea that there are lots of civilisations around. Because if there are then our sort of civilisation must be pretty common. And if we’re not pretty common, then there aren’t going to be many civilisations advanced enough to send visitors.”
This argument, called “Sagan’s paradox,” strengthened the line of thinking that extraterrestrial life exists but has nothing to do with UFOs. This motivated scientists to search the universe for intelligent life without being bothered by the stigma associated with UAP. However, scientists ought to study these UAP with an open mind and expose them, whether they are natural phenomena or figments of imagination.
Today, no scientist is willing to study UAPs out of fear of ruining his or her career. But at some stage, scientists should be bold enough to cross the limits of man-made stigma.