NASA launched a mission to smash a spacecraft into an asteroid to protect the Earth should this giant space rock wipe out life on Earth.
The SpaceX rocket carrying the experiment lifted off from California on Wednesday at 1:21 a.m. Eastern time, NASA launched a mission where the Double Asteroid Redirection Test mission, or DART, from a U.S. Space Force base in California (Tuesday local time) a 1,200-pound, refrigerator-sized spacecraft, the size of a car, will trek around the sun to crash into a small asteroid named Dimorphos ‘moonlet’ at 15,000 miles per hour next year. If the mission succeeds, it could exhibit for the first time humanity’s ability to strike and destroy a potentially perilous asteroid away from Earth.
The attack should take place in the third quarter of 2022 when the binary asteroid system is 11 million kilometres (6.8 million miles) from Earth, almost the nearest point they ever get.
“What we’re trying to learn is how to deflect a threat,” NASA’s top scientist Thomas Zuburchen said of the $330m project is the first of its kind.
While asteroids, in general, pose no threat to the planet, they belong to a class of bodies known as Near-Earth Objects (NEOs), which approach within 48 million kilometres (30 million miles).
NASA’s Planetary Defense Coordination Office is most interested in those larger than 140 metres (460 feet) in size, which have the potential to level entire cities or regions with many times the energy of the average nuclear bomb.
There are 10,000 known near-Earth asteroids that size or greater, but none has a significant chance of hitting in the next 100 years. One big caveat: scientists think there are still 15,000 more such objects waiting to be discovered.
Planetary scientist Essam Heggy said while the NASA mission sounds like science fiction, the threat to the planet is real if the fate of the dinosaurs 80 million years ago is recalled.
“The chances of getting hit again by an asteroid is far from science fiction,” he told Al Jazeera. “Asteroids 100 metres and greater are a threat to the Earth, and we need to quantify our deflection capability to these threats.”
Scientists say the Didymos-Dimorphos system is an “ideal natural laboratory” because Earth-based telescopes can easily measure the brightness variation of the pair and judge the time it takes the moonlet to orbit its big brother.
Since the current orbit period is known, the change will reveal the effect of the collision, scheduled to occur between September 26 and October 1, 2022.
What is more, since the asteroids’ orbit never intersects Earth, they are thought safer to study.
There is some uncertainty about how much energy will be transferred by the impact because the moonlet’s internal composition and porosity are not known.
The more debris that is generated, the more push will be imparted on Dimorphos.
The DART spacecraft also contains sophisticated instruments for navigation and imaging, including the Italian Space Agency’s Light Italian CubeSat for Imaging of Asteroids (LICIACube) to watch the crash and its after-effects.
“The CubeSat is going to give us, we hope, the shot – the most spectacular image of DART’s impact and the ejecta plume coming off the asteroid. That will be a truly historic, spectacular image,” said Tom Statler, DART’s programme scientist.
The so-called “kinetic impactor” method is not the only way to divert an asteroid, but it is the only technique ready to deploy with current technology.
Others that have been hypothesised include flying a spacecraft close by to impart a small gravitational force.
It is believed that asteroids that are 10km (6 miles) or wider – such as the one that struck 66 million years ago led to the extinction of most life on Earth, including the dinosaurs – and this occurs every 100-200 million years.
DART is the latest of several NASA missions of recent years to explore and interact with asteroids, primordial rocky remnants from the solar system’s formation 4.6 billion years ago.
Last month, NASA launched a probe on a voyage to the Trojan asteroid clusters orbiting near Jupiter, while the grab-and-go spacecraft OSIRES-REx is on its way back to Earth with a sample collected last October from the asteroid Bennu.
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