During a mission to deflect a distant asteroid, NASA performed an exceeding expectation on Tuesday, and it was able to demonstrate humanity''s capability to prevent an incoming cosmic object from ruining life on Earth.
On September 26, a fridge-sized Double Asteroid Redirection Test (DART) impactor was deliberately smashed into Dimorphos, causing it to reach a smaller, faster space around its big brother Didymos, according to NASA''s bill Nelson.
That cut the course of orbit by four percent, or 32 minutes from 11 hour 55 minutes to 11 hour 23 minutes, boosting the chance of ten minutes.
"At some point in the future, if we find an asteroid that is threatening to hit Earth, and would be large enough to really do some damage, we will have had this successful test," Nelson told AFP.
Every 2.1 years, the asteroid pair loop together around our Sun, and they pose no threat to our planet.
They are ideal for exploring the "kinetic impact" method of planetary defense.
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DART''s success as a proof-of-concept has allowed for what was once science fiction, particularly "Armageddon," "Deep Impact," and "Don''t Look Up."
Dimorphos, which is 530 feet (160 meters) long or roughly the size of a huge Egyptian pyramid, appeared as a speck of light around an hour before its impact was never actually photographed.
In the last few moments, DART finally came up close to it, reaching around 14,500 miles per hour.
Pseudo-comet
In the days following, astronomers marveled at how matter spreads out thousands of miles pictures collected by Earth and space telescopes, as well as a tiny companion satellite that flew to the zone with DART.
Dimorphos has evolved into a man-made comet owing to its rocky new tail.
For assessing how well the experiment performed, it took a few weeks to clear the difference.
At its launch, the binary asteroid system, which was approximately 6.8 million miles (11 million kilometres) from Earth, is only visible as a single point from the ground.
As Dimorphos approaches to Didymos, the dot''s brightness changes, which is significantly bigger at half-a-mile wide.
According to NASA planetary scientist Nancy Chabot, four optical telescopes were involved in measuring the orbital period in Chile and South Africa.
The experiment also showed scientists that the asteroid is less like a solid rock, rather than a "rubbish pile" of boulders bound by mutual gravity.
If an asteroid is stronger, the spaceship''s momentum will be limited. However, if significant mass is pushed at high velocity in the opposite direction to impact, there will be a bigger boost.
"It appears to be that the recoil from the ejecta blast off the surface was a significant contribution to the global push given to the asteroid," said NASA scientist Tom Statler at a briefing.
He added that the test will serve as a "anchor point" for simulations and calculations regarding the outcome of future impacts.
Mass extinction
According to NASA, no known asteroid that is more than 140 meters in height and enough to devastate a city has a significant chance to strike Earth for the next 100 years.
Wait long enough to get things done.
The geological record demonstrates, for example, that a six-mile wide asteroid struck Earth 66 million years ago, plunging the world into a long winter that resulted in the mass extinction of dinosaurs along with 75 percent of all species.
The agency plans to launch in 2026 a telescope called the Near-Earth Object (NEO) surveyor, which measures potentially dangerous 140-meter asteroids and comets.
So far, less than half of the estimated 25,000 NEOs of 140 meters have been discovered.
Kinetic impact with a spaceship is only one technique to protect the planet, even if it''s the only way to use it with the current technology.
A spaceship might be sent to fly alongside the ship for long enough to divert its path via the ship''s gravitational pull, resulting in a so-called gravity tractor.
Nuclear explosives would be used to redirect or destroy an asteroid, according to the next scenario.
NASA believes that such weapons would be deployed at a distance, without blowing the asteroid to smithers, which would put the Earth in jeopardy.