US space agency NASA recently revealed its Mars Curiosity rover detected surprising quantities of methane – a sign of life on Earth – on the Red Planet. The find briefly fuelled hopes that evidence of alien life might finally been discovered, until the methane was later found to only be “methane transient plumes”. However, the news has not deterred a growing scientific consensus who believe intelligent alien life really could exist elsewhere in the Universe.
Dr Lewis Dartnell, professor of Science Communication at the University of Westminster, told Mashable India “intelligent life could well be out there.”
And this alien life could even resemble animals on Earth, thanks to a process called convergent evolution.
Dr Dartnell said: “If you look at evolution of biology on earth, we can identify some features which we think are for convergence in evolution.
“Convergent evolution is when the same solution is fixed upon by organisms in very different lineages.
“For example, a camera like design of your eye is a very effective way of seeing the world around you and vertebrates have a camera lens type eye which is virtually identical to the one which is evolved by the Octopus.”
“You have a very good reason to expect complex animal life from another planet which have an eye designed similar to ours, because it works in terms of physics and engineering.”
Intelligent life almost certainly does not exist in the solar system outside of Earth.
However, the most basic forms of life could survive on “Mars or maybe the moons of Jupiter”, Dr Dartnell claims.
He said: “We are considering extremophile bacteria like life – hardy micro-organisms, hardy single-celled life.
“But possibly on a more Earth-like planet orbiting another star in our galaxy, there might be a possibility for life to become more complex, the evolution has the opportunity to progress beyond single-celled life.
“We have not discovered a particularly earth like planet yet and we have not certainly not found any life on them yet.
“But if life is there, you can ask yourself what that life might be like.
“What can we deduce or protect from our understanding of evolutionary biology and the principles of physics and designs to predict what compact any life might look like.”
The news comes as astronomers have assembled a “fingerprint” for Earth, capable of identifying an exoplanet able of supporting life.
McGill physics student Evelyn Macdonald and her supervisor Professor Nicolas Cowan used more than a decade of observations of Earth’s atmosphere taken by the SCISAT satellite to construct a type of fingerprint for Earth’s atmosphere in infrared light.
This shows the presence of key molecules in the search for habitable worlds.
This includes the simultaneous presence of ozone and methane, which scientists expect to see only when there is an organic source of these compounds on the planet.
Such a detection is known as a “biosignature.”
Professor Cowan said: ”A handful of researchers have tried to simulate Earth’s transit spectrum, but this is the first empirical infrared transit spectrum of Earth.
“This is what alien astronomers would see if they observed a transit of Earth.”