American space agency Nasa on Wednesday launched a mission to deliberately smash a spacecraft into an asteroid from California. “Asteroid Dimorphos: we’re coming for you!” Nasa tweeted after the launch.
This may sound like science fiction, but the DART (Double Asteroid Redirection Test) is a real proof-of-concept experiment, should humanity ever need to stop a giant space rock from wiping out life on Earth.
The DART lifted off at 10:21 pm Pacific Time Tuesday (0621 GMT Wednesday) aboard a SpaceX rocket from Vandenberg Space Force Base.
What’s the goal of the mission?
The goal is to slightly alter the trajectory of Dimorphos, a “moonlet” around 525 feet (160 meters, or two Statues of Liberty) wide that circles a much larger asteroid called Didymos (2,500 feet in diameter). The pair orbit the Sun together.
When will the impact take place?
Impact should take place in the fall of 2022, between September 26 and October 1, according to Nasa’s planetary defense coordination office. It will be the same time when the binary asteroid system will be 6.8 million miles (11 million kilometers) from Earth, the nearest they ever get, reported news agency AFP.
“What we’re trying to learn is how to deflect a threat,” NASA’s top scientist Thomas Zuburchen said of the $330 million project, the first of its kind.
Do asteroids pose a threat?
To be clear, the asteroids in question pose no threat to our planet. But they belong to a class of bodies known as Near-Earth Objects (NEOs), which approach within 30 million miles.
NASA’s Planetary Defense Coordination Office is most interested in those larger than 460 feet in size, which have the potential to level entire cities or regions with many times the energy of average nuclear bombs.
There are 10,000 known near-Earth asteroids 460 feet in size or greater, but none has a significant chance to hit in the next 100 years. One major caveat: scientists think there are still 15,000 more such objects waiting to be discovered.
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.
(With agency inputs)
