A huge space rock will likely hit Earth again one day, as it did bringing an end to the dinosaurs 66 million years ago. For all the talk of planetary defence by NASA and the European Space Agency (ESA), there is nothing that can be done to stop an asteroid if it is on a collision course with Earth. That, at least, is according to Robert Frost, instructor and flight controller at NASA.
Mr Frost wrote on Q&A site Quora: “Nothing could be done at the present time or in the near future. Any designs on how to prevent such an event are in the speculation and conjecture stages.”
He said there are two options when it comes to prevent an asteroid strike and that is either destroying the space rock or deflecting it from its path.
However, experts do not currently have the means to do either.
Mr Frost continued: “Estimates for the size of Chicxulub, the asteroid that may have killed the dinosaurs 65 million years ago, range from 3 miles (5 km) across to 12 miles (19 km) across.
“Destroying such a massive object would require an immense amount of energy. We currently have neither the capability to destroy such an object nor the capability to reach it far enough away from Earth to inflict such a blow.
“The preferred option is to change the trajectory of the object so that it misses us. A small deflection far away can be a large deflection by the time it reaches us.
“There are designs to perform such deflections, but the technology still needs to be developed.”
While the chances of a major asteroid hitting Earth are small – NASA believes there is a one-in-300,000 chance every year that a space rock which could cause regional damage will hit – the devastating prospect is not impossible.
This is why there are now plans in the pipeline which could help Earth from asteroids.
NASA is currently studying Asteroid Bennu, where its OSIRIS-Rex spacecraft arrived last year.
Its OSIRIS-Rex spacecraft is gathering information about the space rock, which is 500 metres in length.
NASA fears the asteroid, which has the potential to wipe out an entire country on Earth, could hit our planet within the next 120 years, with the next close flyby in 2135.
The mission will give vital information on how to deflect asteroids from their collision course with Earth.
But NASA said while there is a small chance Earth could be impacted, “over millions of years, of all of the planets, Bennu is most likely to hit Venus.”
The ESA has invested £21million in projects such as the Human Exploration Research Analog (Hera) mission, which will study the Didymos binary asteroid, set to fly past Earth in 2022.
Studies such as Hera will help the ESA better understand how it can protect our planet from killer asteroid strikes.