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The Earth-like planet was originally seen crossing its star by Nasa's Kepler space telescope.

Nasa's enormous Hubble telescope will spend about five days over the next year carefully investigating K2-3d.

The hope is that they find a hydrogen-rich atmosphere, or a blanket of clouds, says Dr Björn Benneke at the California Institute of Technology.

Both would be signs of planetary life.

If observations reveal the molecular signature of water, methane or ammonia in K2-3d's atmosphere, it would mean we have a real chance to look for extraterrestrial life.

'If we found any signal, then we would hit K2-3d extremely hard with James Webb Space Telescope [Nasa's successor to the Hubble telescope, which will launch in 2018],' Dr Benneke told New Scientist.

'There's no doubt about that.'

K2-3d is an extrasolar planet, meaning it lies outside of our solar system.

The 'super-Earth' is 1.5 times larger than our planet, and sits around 150 million light years away from Earth.

The planet orbits its host star, a small red star known as 'EPIC 201367065', every 45 days.

The planet orbits very closely to its host star, but because the small star's temperature is so low, K2-3d has a warm, Earth-like climate.

It's possible that liquid water could exist on the surface of the planet, heightening the potential for alien life.

Impending scientific observations will attempt to decipher how likely it is that extraterrestrials lurk on the planet's warm surface.

Typically, such detailed observations can only be made while the planet is partially eclipsing, or in 'transit' of, the host star that it orbits.

And with a transit coming up next year, astronomers are preparing to investigate the planet's atmosphere for life closer than ever before.

Scientists will use enormous telescopes to scour the planet's atmosphere for signs of molecules related to life, such as oxygen and nitrogen.

A team of scientists based at the Okayama Astrophysical Observatory in Japan have now made it possible to view the Super-Earth K2-3d in greater detail than ever before.

The planet's distance from Earth means that observations can only take place when the it is backlit as it eclipses its host star during transit.

Researchers will have to carefully analyse how much starlight is blocked during the transit at a range of wavelengths to precisely calculate the composition of K2-3d's atmosphere.