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Scientists identify 45 planets that could support alien life

seven planetsImage source, NASA
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There are seven planets in the TRAPPIST-1 system among the 45 that could support alien life

According to a new study by astronomers, there are 45 planets that could be our best bet for finding alien life.

They were selected from more than 6,000 identified planets. All of them have rocky surfaces and could, in theory, contain water.

Some of them even have weather systems - including cloud cover, humidity, and wind patterns - similar to what we experience on Earth.

These planets are located in an area known as the TRAPPIST system - also known as the Goldilocks zone.

A bit like the bears' porridge in the famous story, the water on the surface of these planets is not so hot that it boils away and not so cold that it remains permanently frozen - it's just right.

For life to exist as we know it, a planet would also need an atmosphere, a stable climate and the right chemical balance to be a safe habitat.

A planet with half-frozen ocean.Image source, Getty Images
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A planet needs water to sustain life

Among them is a roughly Earth-sized planet circling the nearest star to the Sun, named Proxima Centauri b.

This planet is about 4.2 light years away - more than a whopping 24 trillion miles from Earth!

This means that even if astronauts boarded Voyager 1, the fastest spacecraft yet to leave the solar system, it would take roughly 75,000 years to get there.

So for now, these worlds will have to be explored using the most powerful telescopes we have.

Abigail Bohl of Cornell University, a co-author of the study, explained that her team have used our solar system as a benchmark to analyse the other planets, which are described as exoplanets.

An exoplanet is a planet located outside our solar system, meaning it orbits a star other than our Sun.

"We know Earth is habitable, while Venus and Mars are not," she said.

"We can use our solar system as a reference to search for exoplanets that receive stellar energy between what Venus and Mars get," she said.