Monday 26 September 2022 04:47 PM Space experts deliver their verdict on NASA's DART mission to knock an asteroid ... trends now
Tonight, NASA may just pull off one of its most ambitious feats in its 64-year history.
A NASA spacecraft called DART is due to crash into an asteroid that's about 6.8 million miles away from Earth.
DART was launched from California last November – and finally completes its 10-month journey in the early hours of Tuesday, UK time.
DART's target is the small asteroid Dimorphos, which orbits a larger asteroid called Didymos, around 6.8 million miles away from our planet.
DART will hit the space rock at 15,000mph and be destroyed upon impact, while Dimorphos will merely receive a 'small nudge' to alter its trajectory by a fraction.
If this sounds like the plot from a sci-fi disaster movie, rest assured - neither Dimorphos nor Didymos pose any danger to Earth.
The $325 million (£298 million) mission is merely a rehearsal of what may be required if a space rock does one day threaten our planet.
If a large asteroid was to hit Earth, it could wipe out the human race – much like the demise of the dinosaurs 66 million years ago.
MailOnline has spoken to experts about how the DART mission will be judged a success – and any implications for Earthlings if it fails.
Brace for impact: NASA's first ever 'planetary defence' spacecraft - sent to deflect an asteroid 6.8 million miles from Earth – is set to hit its target on Monday, September 26. The graphic above shows how the mission will work
This artist's illustration obtained from NASA shows the DART spacecraft prior to impact with the asteroid Dimorphos
DART – which is being referred to as a planetary defence mission – marks humanity's first attempt at deflecting an asteroid.
The impact is due to take place on Monday (September 26) at 19:14 ET (00:14 BST Tuesday) and can be watched live on NASA TV and the agency's YouTube channel.
Professor Alan Fitzsimmons from Queen's University Belfast, told MailOnline that completion of the DART mission will give experts 'a much better idea how to protect ourselves against a catastrophic impact'.
'I've been waiting 20 years for a planetary defence test to be performed,' he said.
'DART will give us our first proof that we have the technology to prevent a small asteroid hitting Earth.'
Colin Snodgrass, an astronomer at the University of Edinburgh, said there is the possibility it won't work, but that if this is the case 'there is no real problem'.
'This has never been tried before, it is an experiment,' he told MailOnline. 'So there is always a risk that it doesn't work.
'That is why we do these tests now rather than waiting until we found an asteroid that was actually a danger and we need to do it for real.
'If the mission fails, for example by missing the target, there is no real problem as it is just a test – and NASA would learn from analysis of what went wrong to be able to make sure a future mission would succeed.'
Dr Jonathan McDowell, an astronomer at the Harvard-Smithsonian Center for Astrophysics, highlighted potential issues that could occur tonight.
'The worst case scenario is that we don't get any information back from the mission, due to a communications system failure or something like that,' Dr McDowell told MailOnline.
'The other main way the mission can fail is if there's a problem in the targeting system and DART misses Dimorphos instead of hitting it, in which case it will sail on around the sun.'
DART will smash into Dimorphos, which orbits a larger asteroid called Didymos, at 13,500 miles per hour (21,700 km per hour). The smaller Dimorphos is depicted here to scale with Rome's Colosseum
Dimorphos and Didymos are depicted here to scale with some of Earth's most famous landmarks