The Double Asteroid Redirection Test (DART) has been conducted to see whether humanity has a chance of preventing a catastrophe comparable to the extinction of the dinosaurs.
NASA successfully rammed a spacecraft into an asteroid located seven million kilometers from Earth.
The final photograph captured by the “size of a vending machine” collider revealed the surface of the asteroid Dimorphos mere seconds before the collision.
DART is the first test of a “planetary defense system.
If a device put into space can alter the orbit of an asteroid, humanity may have a chance of avoiding the type of catastrophe that wiped out the dinosaurs.
NASA and their worldwide team of astronomers chose their target with great care. To demonstrate success, they required an asteroid that can be closely monitored after the strike. Additionally, they had to ensure that any hit would not send a previously innocuous rock hurtling toward Earth.
They chose two asteroids: the 780-meter-wide Didymos and its 160-meter-wide moon Dimorphos, which is roughly the size of the Great Pyramid.
Because Dimorphos is already orbiting its larger companion safely, the altered behavior it exhibited after the impact may be studied.
Asteroid Dimorphos is also a rather common size. Although substantially smaller than a kilometer-wide “planet killer,” it is readily capable of destroying a metropolis.
Betsy Congdon, DART’s mechanical systems engineer at Johns Hopkins University in Maryland, explains, “What Dart is going to demonstrate is that we have a system for kinetic deflection, nudging things away and nudging them off course.”
Prepare for minor disappointment if you’ve seen the Hollywood disaster films Deep Impact, Armageddon, or more recently Don’t Look Up.
Despite crashing a half-tonne spacecraft into Dimorphos at close to 15,000 miles per hour, the impact on the asteroid is predicted to be negligible, slowing it by only 0.4mm per second.
However, this should have a measurable impact on its orbit over time. To determine the outcome of the test, a variety of terrestrial and space-based observatories, including NASA and ESA’s new James Webb Space Telescope, will examine the asteroid.
Although it is a small objective, the engineering required to achieve it was extensive. Didymos is too small and distant for the DART spacecraft to reach Earth.
The probe had to employ an automated guiding system to target the asteroid, which was so small that it was not visible to DART’s cameras until approximately 50 minutes before impact. However, the sat-nav seemed to have performed flawlessly.
If the impact is sufficiently far, it is hoped that a little nudge will be sufficient to deflect a future asteroid on a collision course with Earth.
Astronomers estimate that they have traced the orbits of 95 percent of asteroids huge enough to wipe out all life on Earth, and none of them are currently on a crash route.
However, there are several smaller ones. According to NASA, no asteroids larger than 140 meters in diameter are expected to strike Earth during the next 100 years. However, they estimate that they have only located 40% of them.
Before 66 million years ago, a 10-kilometer-wide asteroid struck the Yucatan Peninsula of Mexico. It left behind a 110-mile-wide, 12-mile-deep crater.
It is believed that the resultant change in the planet’s temperature produced the Cretaceous-Paleogene extinction disaster. The impact wiped off 75 percent of Earth’s animal and plant species, including the flightless dinosaurs.
However, even little space objects might cause problems on Earth. In 2013, a 20-meter-wide asteroid erupted over the Russian city of Chelyabinsk in the Ural area.
About a third of the force of the Hiroshima bomb, the explosion was comparable to 500 tonnes of TNT. While no fatalities were reported, there were over 1,400 injuries, some of which were severe.
Prof. Colin Snodgrass of the University of Edinburgh, who is a member of the DART team, said, “An asteroid impact is the only type of natural calamity that might be predicted decades in advance.”
He assisted in the installation of a telescope in Kenya to observe Earth’s impact. If one [of the magnitude of Dimorphos] were ever discovered approaching Earth, it would seem prudent to have the technology to deal with it.
