European Space Agency’s space probe Hera, now set to switch fields to a
detective, as ESA gears up to launch it on monday to investigate a crash
site at an asteroid.
A scene sounding straight out of science fiction played out as a spacecraft
intentionally crashed into the pyramid-sized asteroid Dimorphos last year,
some 11 million kilometers (6.8 million miles) from Earth. A fridge-sized impactor used in the Double Asteroid Redirection Test knocks the asteroid completely off its course.
The DART effectively demonstrated that the concept worked: mankind may no longer stand powerless against potentially planet-killing asteroids that could come their way in the future.
But much about the impact remains a mystery, including the extent of damage inflicted and exactly what the asteroid was like before it was hit. So, the European Space Agency said it is sending Hera to the asteroid to conduct a kind of "crime scene investigation" in the hope of learning how
Earth might best fend off the shooting stars that pose some threat.
The spacecraft is scheduled to be flown on Monday using a SpaceX Falcon
9, from Cape Canaveral, Florida.
Curse of Anomalies
However, an "anomaly" with the Falcon 9 rocket from the launch of the SpaceX astronauts on Saturday may delay the launch date, said ESA's Hera project manager Ian Carnelli at a press conference. The window of launching the mission remains open until October 27.
The ESA hopes to get a nod in time on Sunday by the US Federal Aviation
Administration, NASA and SpaceX, Carnelli said. As soon as it's launched, Hera is scheduled to fly by Mars early next year
and then catch up with Dimorphos in December 2026 to start its six-month
study.
A kilometer-wide (0.6 miles) asteroid-such as the one that could be capable of inflicting a global cataclysm on the order of the one that, again, wiped out the dinosaurs-is thought to strike Earth every 500,000 years or so. Every 20,000 years or so, a space rock about 140 meters in diameter—a bit smaller than Dimorphos but potentially large enough to wipe out a large city—strikes our home planet.
Most such space rocks come from the asteroid belt between Mars and Jupiter. Nine hundred ninety-nine percent of all those with diameters greater than 1 kilometer are cataloged by scientists, and none of them threaten Earth in the next century. There aren’t any 140-meter asteroids on a collision course with Earth-however scientists say that only 40 percent of such space rocks have actually been identified.
This may be one of the least likely natural disasters to strike the planet, but people now have the "advantage of being able to protect ourselves against them", according to Hera mission's principal investigator Patrick Michel.
A moonlet called Dimorphos, technically orbiting the larger brother Didymos, was never a threat to Earth to start with. It took an impact by DART so that Dimorphos lost the material to an extent that its orbit around Didymos got curtailed by 33 minutes-the point of proof that it had been deviated successfully.
Instead of a hard rock, as was envisioned earlier, it is only recently that evidence has come up through the analysis of the DART mission about Dimorphos itself being an assortment of dust and stone held together by gravity.
The result of this is that, instead of “cratering” Dimorphos, DART may have "completely deformed the asteroid," Michel said. "the behavior of these low-gravity objects is little understood and defies intuition", Were the words of Michel, sparking thoughts that other possibilities may exist.
The 363-million-euro ($400 million) mission will be equipped with 12 scientific instruments and two nanosatellites. The Juventas nanosatellite will aim to land on Dimorphos; this will be the first time ever landing on an asteroid of this size. It is planned to be equipped with a radar that shall penetrate through the asteroid, scanning it from the inside, and with a gravimeter to map out its gravity field.
The Milani nanosatellite, further from Dimorphos, will observe the composition of the asteroid using cameras and other instruments. The impact of the DART mission will be assessed.
Once its task is done, scientists are hoping Hera can safely touch down on
Dimorphous or Didymos, where it will spend the remainder of its days.
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