Galaxy ‘could be filled with Earth-like planets’

JUST as imagined in the TV series Star Trek, the galaxy really could be filled with Earth-like planets capable of supporting life, new research suggests.

A study of nearby stars similar to the Sun shows that almost one in four could have Earth-size planets.

They have only not been detected yet because of the technical difficulties involved, scientists believe.

Many of these worlds may occupy the fabled “Goldilocks zone” — the orbital path where conditions are not too hot or cold but “just right” to support liquid surface water, and possibly life.

Astronomers in the US came to the conclusion after spending five years studying 166 Sun-like stars within 80 light years of Earth.

They found increasing numbers of smaller planets, with the highest proportion being so-called “super- Earths” which are the smallest size detectable today.

Dr Andrew Howard, from the University of California at Berkeley, said: “Of about 100 typical Sun-like stars, one or two have planets the size of Jupiter, roughly six have a planet the size of Neptune, and about 12 have super-Earths between three and 10 Earth masses.

“If we extrapolate down to Earth-size planets — between one-half and two times the mass of Earth — we predict that you’d find about 23 for every 100 stars.”

The technique the astronomers used could only detect planets close to their stars. Taking this into account, there could be an even higher proportion of Earth-size planets at greater distances, including ones within the habitable “Goldilocks zone”.

Over the next decade, new methods of planet detection and more powerful telescopes could soon be uncovering true Earth-like worlds orbiting distant stars, the scientists said.

The findings, reported in the journal Science, conflict with current models of planet formation which predict empty “deserts” in the inner regions of solar systems.

In reality, the inner zones appeared to contain the greatest numbers of planets.