Humans have been trying to find alien life for a century or longer, and we tend to think it must be many light years away, in the deepest recess of a distant galaxy.
But Nasa – who know more than most of us – think it could be in our own celestial backyard, and will be launching a rocket this afternoon to try and find it.
At 5.06pm UK time, a spacecraft is scheduled to launch on a journey which will take it 1.8 billion miles through our solar system, to the biggest planet Jupiter where it will study one of its many moons, called Europa.
‘There’s scientific evidence that the ingredients for life may exist on Europa right now,’ Nasa said.
Although scientists are not expecting to find evidence of little green men living beneath the moon’s icy shell, they will look at whether there are conditions which could potentially allow lifeforms to exist there.
If they do find microbes or even something more complex, it would show that life formed independently in two places around the same star (the sun).
This would suggest that life could spring up ‘fairly easily once the necessary ingredients are present, and that life might be found throughout our galaxy and the universe,’ Nasa said.
Europa is thought to contain more water than even our own planet, but its salt water ocean is locked underneath thick layers of ice.
Inside that icy water-world, there could be the building blocks for life. And if so, it could indicate we’re not as lonely as we thought in space.
Europa Clipper will orbit Jupiter and conduct 49 close flybys of its fourth-largest moon in the £3.8 billion mission.
It will be a while before it reports back, however, because it won’t even get there until April 2030, even if all goes to plan.
The launch from the Kennedy Space Centre in Florida from was meant to take place last week, but had to be delayed while Hurricane Milton cut a devastating track through the state.
Conditions are now good for the craft to be launched today on its journey from a SpaceX Falcon Heavy rocket.
Europa, Jupiter’s fourth largest moon
From previous observations, scientists think Europa’s ice shell is 10 to 15 miles thick, floating on an ocean 40 to 100 miles deep. While Europa is only a quarter of the size of Earth, its ocean could have twice as much water.
With a diameter of 1,940 miles, Europa is about 90% the size of Earth’s Moon.
Although it is a similar size, it is much brighter, because the water ice on its surface reflects over five times the amount of sunlight as our own rocky moon.
Life on the surface of Europa could not survive as it would be blasted by radiation from Jupiter.
But it is thought that the radiation may create fuel for life in an ocean below the surface.
Source: Nasa.
It will not have enough fuel to power it all the way to Jupiter, so to get there it will take a helping hand from the gravity of Earth and then Mars like a slingshot, before the engines fire back up when it gets closer.
Europe is considered one of the most promising ‘potentially habitable’ environments in the solar system.
The spacecraft, the largest NASA has ever developed for a planetary mission, will carry a suite of nine instruments along with a gravity experiment that will investigate the ocean beneath Europa’s surface.
If you want to watch along this afternoon, the launch will be live streamed by Nasa.
Get in touch with our news team by emailing us at [email protected].
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