tonight, the hunt for extra planets.
Planets just like ours orbiting stars in different solar system.
Where are they hiding?
Can they support life?
And when exactly can we move there because we've screwed up this planet and I want to leave.
I'm Claire Reilly, welcome to Watch This Space.
From the CNET Studios in Sydney this is your weekly guide to everything on Earth you need to know about space.
And tonight, we're all alone in the Universe, or are we?
Well, probably, but maybe not.
We're on the hunt for exoplanets, and we're not going to stop looking under the giant intergalactic couch til we've found all of them.
Exoplanets are like regular planets, but they exist outside our solar system, orbiting around their own stars.
They're also called extrasolar planets Because just like your friend who turns up to every birthday party in a different Lures jumpsuit, they're just a little bit extra.
We've known about exoplanets for decades and we had our first confirm discovery of one in 1995.
Since then our exoplanet hunt has been going off like a frog in a sock.
According to NASA we've had more than 3,700 confirmed discoveries of exoplanets in just a couple of decades.
With a further 2,900 potential candidate planets that is still unconfirmed.
They could be a good match but scientists still haven't swapped right on them yet.
In total we've discovered more than 2,800 planetary systems.
Stars and have their own planets just hanging out nearby.
Just like the planets in our own solar system they are all really different.
Some of them might have rings like Saturn, others could have water.
Some of them are massive and some are close in size to Earth.
And then there's planets like HD189733B where it rains glass sideways And which Wikipedia has called a hot Jupiter with poor prospects for extraterrestrial life.
That's right, the popular girl at your Halloween party isn't the only one trying to be a hot Jupiter this year.
And speaking of HD 189733b, let's talk about those names Exoplanet names sound like they're pulled from the world's most boring index card catalog.
Or from your uncle's Star Trek fanfic.
Yeah, I'm looking at you, Draugr.
So why the weird names?
Well, because if we left it to an Internet vote, the public would probably try to name them all Pluto and McPluto Face, or Mr. Starry Pants.
So the International Astronomical Union has created a naming convention.
To help sort those thousands of exoplanets out.
Some are named after their star like 51 Pegasi B or the astronomer that catalogued them, like Gliese 581 named after German astronomer Wilhelm Gliese.
And then there are those named after the instrument that found them, like noted Super Earth Kepler-440B.
You've heard of Kepler.
I thought you might say that, that brings us to this week's edition of Kepler, I hardly knew her.
Over to you, Claire.
That's right Claire, Kepler is something of a superstar in the exo planet hunting game.
Launched in 2009 and named after 17th century astronomy bad boy, Yohan Kepler, the space craft's mission is to To find what NASA calls earth analogs, planets similar to our own orbiting a star like our sun.
Since blasting off almost a decade ago, Kepler has found more than 2,600 exoplanets Planets and almost 3,000 exoplanet candidates.
So how does it find them?
Well, it looks for dips in a star's brightness.
That kind of dimming could indicate that a planet is passing between Kepler and the star and that could be a sign of an orbiting exoplanet.
Kepler is equipped with a 95 megapixel camera array.
That's the largest camera ever launched into space according to NASA.
And its telescope is so powerful that even from space it could detect a single a porch light turning off at night.
Back to you in the studio, Claire.
I think I'll be leaving my porch lights on tonight.
There have been a whole raft of instruments that have helped us find extra planets from telescopes here on Earth to the hobble telescope and even the new transiting extra planet survey satellite or TES.
TES finally began science operations in 2018 but Kepler has been in action for years and it's big focus has been on finding Earth-like planets in the so-called habitable zone.
This is the orbital distance around the star where the conditions and temperatures are just right for life.
It's also known as the Goldilocks zone.
The Goldilocks zone is far enough from the sun, so.
It's not too hard, but close enough so it's not too cold.
The temperature has to be just right for liquid water to exist on the surface of the planet and not turn into terrifying sideways glass rain.
[SOUND] Cut to b roll.
It took about a billion years for life to appear after earth was formed, so these exoplanets can't little baby things.
That means, Goldilocks is gonna have to grow up a bit before she'll be able to grow any microscopic bacteria or algae slimes.
One day Goldilocks.
Either way Kepler could be the key to finding our planet's long lost cousin.
Our earth from another birth if you will.
But Kepler might not be around for long.
The spacecraft was originally slated to run out of fuel in 2018, and NASA doesn't know how much it has left.
It's been in and out of hibernation, going into sleep mode to conserve fuel, so it can use its last remaining energy to send back crucial observational data.
When Kepler does die and slip off into the great beyond, our search for exoplanets won't be over.
We'll still have tests to help us find weird and wonderful new worlds.
All right, that's it for this week's episode of Watch This Space.
If you've enjoyed the show, then be sure to click the Like button on your remote, and subscribe for more space news as it happens.
I'm Claire Reilly for CNet, goodnight and Godspeed.