A Belfast astronomer is on a mission.
Professor Alan Fitzsimmons is calling for amateur astronomers to help a multinational space mission which could ultimately help save Earth.
The Queens University Belfast professor says the Hera mission is designed to calculate how to stop asteroids colliding with the planet but they need help deciding which asteroids to observe.
Is there a potentially lethal asteroid out there, just waiting for us?
"We will get a serious asteroid impact sometime," says Prof Fitzsimmons.
"It may not be in our lifetime, but mother nature controls when that will happen.
"We will need to do something about it. We'll need to move that asteroid so it misses us and and doesn't hit us," explains Prof Fitzsimmons.
"We can do as many calculations as we like and we have done on paper but until you try it and check your calculations you don't know if you're going to succeed or not.
"That's why Hera is so important - it's our test to see whether or not we can shift an asteroid so it doesn't hit Earth."
Learning 'to deflect asteroids'
Nasa's Double Asteroid Redirection Test (Dart) and European Space Agency's (ESA) Hera will be on their way to assess mankind's chance of stopping an asteroid that is much bigger.
The Hera spacecraft, launching in 2024, is on a mission to measure the movement of a small asteroid moon beside a bigger one called Didymos.
It will have been moving, because a couple of years earlier NASA is going to hit the moon of an asteroid with its own spacecraft, leaving the Europeans with the Hera mission to measure how good a job they did.
"We're just happy we can go there now and find out how we can deflect asteroids in the future," he says.
Prof Fitzsimmons now needs the help of some amateur astronomers for the time Hera passes through the asteroid belt on its way to do the job.
"Asteroid research is one area of astronomy where amateur observes continue to make an essential contribution," he says.
"There are many out there both in Ireland, the UK, Europe and around the world who regularly track asteroids and even measure how their brightness changes with time.
"That's particularly what we're looking for - these advanced amateurs," he adds.
So, if you want help the world's foremost space agencies watch the skies, now is your time.