An asteroid is hurdling toward Earth, and NASA is going to stop it. At 1:21 a.m. EST, Nov. 24 (06:21 UTC), the Double Asteroid Redirection Test (DART) spacecraft is scheduled to launch from Vandenberg Air Force Base in California, embarking on a suicide mission to deflect an asteroid’s trajectory.
Humans shouldn’t be too worried; the 558-foot asteroid named Dimorphos poses no actual threat to Earth. The mission, however, will be the world’s first test of asteroid deflection technology in preparation for a real code-red scenario down the line. Data from the demonstration will help scientists prevent all of us from ending up like the dinosaurs.
Almost 310 million miles away, Dimorphos is orbiting the Sun on a path that will sling it near Earth’s orbit and past Mars. Despite stretching about one-and-a-half football fields long, it pales in comparison to its nearly five times bigger sister, Didymos, with which it forms a double asteroid system.
Dart is much smaller (only about the mass of a brown bear), but it only needs a small punch to slightly alter Dimorphos’s trajectory. It is unique for being a spacecraft NASA builds with the intention of destroying.
After Dart lifts off on a SpaceX Falcon 9 rocket, onlookers will be able to watch it pass over the west coast of South America then east across the Atlantic, finally appearing above the horizon as seen from Australia.
Sixty minutes from launch, the spacecraft will separate from the launcher, its transponder will turn on, and ESA’s antenna in Australia will capture its very first words – the “acquisition of signal.”
Then begins its 11-month journey toward certain death. As NASA monitors the spacecraft, it will home in on Dimorphos before striking the asteroid at a speed of 4.1 miles per second in October 2022.
ESA’s antennae in Australia and Argentina will allow mission controllers to know the precise position of DART hundreds of millions of miles away. With a line of communication open, NASA can ensure the spacecraft’s well-being and send commands to it if necessary.
By the time Dart intercepts Dimorphos, it will be within seven million miles from Earth.
Ten days before impact, as Dimorphos comes into view, Dart will deploy the LICIACube, a hand-sized CubeSat from the Italian Space Agency. As if taking a selfie before driving into a brick wall, Dart’s collision and subsequent plume of materials will be streamed home via the LICIACube.
In addition to the spectacle, the live footage will provide NASA with 24/7 observations of the target asteroid, something NASA’s Deep Space Network cannot provide on its own.
In November 2024, ESA’s Hera mission will head towards the Didymos binary system, then conduct a “crime scene investigation” of the asteroids in late 2026.
The data gathered will hopefully help scientists develop a reliable method of deflecting asteroids.
While no known asteroid larger than 459 feet in size has a significant chance to hit Earth for the next 100 years, only about 40 percent of those asteroids have been found as of October 2021.