The Scotsman

Planet 1,400 light years away the most likely to support life, say scientists

- By JOHN VON RADOWITZ

0 Kepler 452b: the planet most likely to support alien life A “super-earth” 1,400 light years away has emerged as the exoplanet most likely of any known to support alien life.

Kepler 452b, discovered in 2015, lies in the middle of a newly identified “abiogenesi­s zone” where the right conditions exist for life to be spawned by starlight and chemistry.

The planet, which has a radi- us 1.5 times that of Earth, also orbits inside the “habitable” or “Goldilocks” zone with temperatur­es not too hot and not too cold to permit liquid surface water.

Almost 4,000 planets have now been discovered orbiting stars other than the sun. Of these, only about 50 are known to occupy their star’s habitable zone.

However, just one – Kepler 452b – also falls inside the abiogenesi­s zone.

A planet in the abiogenesi­s zone is bathed in the right level and type of ultraviole­t radiation from its star to kick-start chemical reactions thought to have given birth to life on Earth.

Scientists at Cambridge University coined the term after conducting a series of laboratory experiment­s mimicking the creation of life’s building blocks.

A leading theory for the way life began on Earth is that it emerged from chemical reactions involving hydrogen cyanide and hydrogen sulphite, powered by sunlight.

Duplicatin­g earlier work conducted in 2015, the Cambridge researcher­s created the precursors of lipids, amino acids and nucleotide­s – all essential components of living cells.

They then went a step further by comparing the UV light used in the laboratory to that generated by different stars.

Generally the most sun-like stars were found to emit the right sort of light to trigger the formation of life’s building blocks on planets.

Kepler 452, in the constellat­ion of Cygnus, is about 20 per cent brighter than the sun and some two billion years older.

The planet 452b has been called “Earth’s cousin”. Computer simulation­s suggest it has a thick atmosphere, liquid surface water, and active volcanoes.

 ??  ??

Newspapers in English

Newspapers from United Kingdom