CAPE CANAVERAL, Florida – A spacecraft launched Monday to probe the site of a cosmic accident.
The European Space Agency’s Hera spacecraft launched on a two-year trip to the little, harmless asteroid slammed by NASA two years ago as a practice run for the day when a murderous space rock threatens Earth. It’s the second phase of a planetary defense experiment that could one day save the globe.
SpaceX’s Falcon rocket vanished with Hera into the late morning clouds. An hour later, cheering erupted in the control center in Germany as the spacecraft split from the rocket’s upper stage and returned home. “It’s an amazing day,” the space agency’s director general, Josef Aschbacher, said later.
The 2022 crash of NASA’s Dart spacecraft reduced Dimorphos’ orbit around its larger companion, indicating that if a harmful rock was heading our way, it might be pushed off course with adequate warning.
A Spacecraft Is On Its Way To A Harmless Asteroid Slammed By NASA In A Previous Save-The-Earth Test
Scientists are eager to analyze the aftermath of the impact up close to determine how effective Dart was and what improvements may be required to protect Earth in the future.
“The more detail we can glean the better as it may be important for planning a future deflection mission should one be needed,” University of Maryland astronomer Derek Richardson stated before launch.
Researchers want to know if Dart (short for Double Asteroid Redirection Test) created a crater or changed the 500-foot (150-meter) asteroid more dramatically. It seemed to be a flying saucer before Dart’s blow and may now resemble a kidney bean, according to Richardson, who participated in the Dart mission and is assisting Hera.
Dart’s wallop sent rubble and boulders hurtling off Dimorphos, adding to the impact’s momentum. For months, the debris track extended thousands of miles (almost 10,000 kilometers) into space.
According to flight director Ignacio Tanco, some rocks and debris may still be hovering about the asteroid, posing a threat to Hera.
A Spacecraft Is On Its Way To A Harmless Asteroid Slammed By NASA In A Previous Save-The-Earth Test
“We don’t really know very well the environment in which we are going to operate,” Tanco informed me. “But that’s the whole point of the mission is to go there and find out.”
European authorities refer to the $400 million (363 million euros) effort as a “crash scene investigation.”
“Hera is going back to the crime scene and getting all the scientific and technical information,” said project manager Ian Carnelli.
Carrying a dozen science instruments, the compact car-sized Hera must swing past Mars in 2025 for a gravitational boost before landing at Dimorphos by the end of 2026. It’s a moonlet of Didymos, the Greek word for twin, a five-times larger asteroid that spins quickly. At that point, the asteroids will be 120 million miles (195 million kilometers) from Earth.
Hera will attempt to enter orbit around the rocky duo, progressively reducing flyby distances from 18 miles (30 kilometers) to a half-mile (1 kilometer). The spacecraft will examine the moonlet for at least six months to determine its mass, shape, composition, and orbit around Didymos.
Before the crash, Dimorphos circled its larger partner from three-quarters of a mile (1,189 meters) away. Scientists believe the orbit has become tighter and more oval-shaped, and that the moonlet may be tumbling.
Two shoebox-sized Cubesats will launch from Hera for even closer drone-like examinations, with one employing radar to peek beneath the moonlet’s boulder-strewn surface. Scientists believe Dimorphos was produced from particles shed by Didymos. The radar measurements should assist in determining whether Didymos is the small moon’s parent.
A Spacecraft Is On Its Way To A Harmless Asteroid Slammed By NASA In A Previous Save-The-Earth Test
After their survey, the CubeSats will attempt to land on the moonlet. If the moonlet tumbles, the situation will become more complicated. Hera may potentially conclude its mission with a perilous touchdown but on the bigger Didymos.
Asteroids, which are remnants of the solar system’s origin 4.6 billion years ago, circle the sun principally between Mars and Jupiter in what is known as the main asteroid belt, where millions of them live. When they fall from the belt and land in our area, they become near-Earth objects.
NASA now has around 36,000 near-Earth objects, the majority of which are asteroids, although there are also some comets. More than 2,400 of them are deemed potentially dangerous to the Earth.
SOURCE | AP
