NASA May Be About To Reveal The Discovery Of A New 'Earth'

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Yes, we know it sounds like a lavish PR stunt for the next major Hollywood sci-fi epic, but we've checked the speaker list and Tom Cruise isn't appearing.

At 17:00 GMT on 23 July, NASA will hold a press conference to announce the latest findings of its planet-hunting Kepler mission. There's a change they could make an announcement that could chance the course of... well, everything human kind is doing with space. Here's why.

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Launched in March 2009, NASA's Kepler spacecraft has been using one of the world's most powerful photometers (basically a telescope that looks for light) to probe the deepest, darkest corners of space. It's mission? To look for far off planets (or exoplanets, to be exact) - particularly those that hold the potential for the formation of liquid water and sit within a "habitable zone" of the star it orbits. They're looking for another Earth.

The "habitable zone" is hugely important for finding an Earth-like planet: too close to a star, and the surface will likely be a molten vat of horribleness, too far and it could be a frozen desert. 

The Kepler spots these planetary bodies by looking for a "transit event", which has nothing to do with white vans, but rather a tiny dip in the light levels given off by a distant star.

This indicates that something has passed in front of the star in its orbit, allowing NASA to determine a bunch of properties, from its size to whether it sits in a habitable zone.

So far, the Kepler mission has spotted 1,000 planets, and a further 3,000 possible planets. At their press briefing today, NASA will announce the Kepler's latest findings - which could well include an Earth-sized planet, sitting in a habitable zone.

Should that be the case, NASA could point a whole heap of equipment, researchers and tech, at the spot of sky that this Earth candidate sits in, allowing us to find out (or have a good guess) if it really could be awash with oceans, mountains and - just possibly - life.

It could be the first of many, or just a one-off - but it's the sort of discovery that means future trips into the big black could be pointed at this discovery. Sure, we won't visit it for a very, very long time, but it's something to aim at, right?

We'll find out for sure when NASA reveals all at 17:00. You'll be able to watch the press conference stream right here.

If you need us, we'll be watching Star Trek episodes on repeat until then.

(Images: NASA)