What should we do if we find a dangerous asteroid on course to hit Earth?
Well, there are a number of possible deflection techniques, ranging from extreme nuclear blasts or using a heavy spacecraft which uses gravity to change the course of the asteroid. In such a case, slamming one or more spacecraft into the asteroid at high speed to change its orbit and move Earth out of the crosshairs. This technique works particularly well if used far in advance.
DART, NASA's Double Asteroid Redirection Test, is the first space mission to test this or any other asteroid deflection technique. With the success of the mission and the altering of the orbit of the asteroid Dimorphos, NASA did the unthinkable.
For the first time in history, humans were able to shake and move a celestial body. The collision of the spacecraft with the asteroid was supposed to move it away from its usual orbit. This event has just avoided another dinosaur-extinction event.
Before the mission, NASA had set some tangible goals which would tell if the mission gave desired results or not. One of them was a change in the asteroid's orbital velocity. The target was a change of 73 seconds or more in Dimorphos orbital speed. Astoundingly, NASA has beaten this target by more than 25 times.
The investigation team has confirmed the alteration.
The administrator of NASA, Bill Nelson said, 'All of us have a responsibility to protect our home.' The success of the mission shows that NASA is trying to be ready for whatever the universe throws at us. It has proven that we are as serious as a defender of the planet. This is a watershed moment for planetary defense and all of humanity.
The job is still not over yet. The focus will now shift towards measuring the efficiency of momentum transfer from DART's roughly collision with its target. This will also include analyzing the asteroidal rock and dust that got dispersed into space as a result of the impact. If the efficiency of momentum transfer would be low, NASA would work to improve the spacecraft further.
Indeed, this is a very exciting and promising result for planetary defense.
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