Picture: NASA.
NASA has completed its first-ever attempt to move an asteroid as part of its planetary defense strategy.
The DART (Double Asteroid Redirection Test) probe targeted Dimorphos, a small egg-shaped asteroid that orbited the much larger Didymos. Neither of these two asteroids posed a threat to Earth, but NASA used DART to demonstrate that it was possible to hit an asteroid like Dimorphos if it were to discover a similar body in Earth’s path.
For Bill Nelson, Administrator of NASA, “reality met science fiction” when the space agency demonstrated that there really was “a way to protect the Earth”.
Divert the trajectory
The Dart probe slammed into Dimorphos at 7:14 p.m. EDT (1:14 a.m. French time), according to DART mission control at the Johns Hopkins Applied Physics Laboratory in Laurel, Md., which manages NASA’s planetary defense strategy.
The probe was destroyed after the impact succeeded. It is now a question of discovering to what extent it modified the orbit of Dimorphos around Didymos.
The impact was expected to shorten Dimorphos’ orbit by about 1%, or about 10 minutes. NASA now wants to measure precisely how much the asteroid has been deflected.
A technical feat
The impact on Dimorphos was a technical feat in itself. DART, a spacecraft the size of a small car, weighs only 570 kilograms. It headed towards its target at a speed of approximately 22,530 km/h. It was launched on November 24, 2021.
Dimorphos and Didymos are about 11 million kilometers from Earth. The first has a diameter of approximately 160 meters, while the second has a diameter of 780 meters. To give you an idea, its circumference is more than twice the height of the Eiffel Tower (which is around 300 meters).
The final seconds of footage taken by the EICC’s DRACO camera shows it passing the yam-shaped Didymos and heading directly towards Dimorphos, whose rocky surface fills the field of view before the camera swerves. turn off. The large antennas of the EICC allowed the DRACO to transmit the images live to Earth.
Mission accomplished ?
For Carolyn Ernst, DART DRACO specialist at the Johns Hopkins Applied Physics Laboratory, Dimorphos is an “amazing” and “terribly ovoid” asteroid.
“Once we saw Dimorphos, I think the team was convinced we were going to hit it,” says Mark Jensenius, DART smart ship guidance engineer at the same lab.
NASA has yet to determine if the target has been hit. Nevertheless, the agency has already announced that the exercise was a success, and that this should reassure the inhabitants of the planet.
Answer in a few months
“We were about 17 meters away, which allowed us to get very close, and we will have a better idea of our position thanks to the impact images which the investigation team will analyze for some time,” explains Lena Adams, DART’s mission systems engineer.
The latter specifies that it will probably take a few months to obtain a clear picture of the extent of the change in orbit of Dimorphos due to the impact.
“I definitely think that, as far as we can tell, our first planetary defense test was a success and I think we can applaud that. Yes, I think Earthlings should sleep better – in any case, I will, ”she reassures nevertheless.
Waiting for pictures
DART’s DRACO camera is no longer in service, but 15 days before impact it deployed the Italian Space Agency’s Light Italian CubeSat for Imaging of Asteroids (LICIACube).
This camera was used to capture images of the DART impact and the cloud of material ejected by the asteroid. It will provide images showing the effect of the collision, which will help researchers determine how effective a collision with the asteroid was in deflecting it.
LICIACube being devoid of antennas, the images will be transmitted to Earth one by one in the coming weeks, specifies NASA.
Source: ZDNet.com