export_ofoct.com

[00:00.67] A European spacecraft has been launched to explore an asteroid struck in an earlier planetary defense mission by the American space agency NASA.

[00:15.28] The European Space Agency (ESA’s) Hera spacecraft launched October 7 from NASA’s Cape Canaveral in Florida.

[00:26.70] The spacecraft, or probe, was carried to space aboard a SpaceX Falcon 9 rocket.

[00:35.73] Hera is headed to the asteroid Dimorphos.

[00:40.78] NASA crashed its DART spacecraft into the space rock in 2022 in an area about 11 million kilometers from Earth.

[00:53.79] The NASA mission was an experiment to test a method for changing the orbit of asteroids that might one day threaten Earth.

[01:05.48] NASA has said its own studies of the crash showed it was successful because the force of the strike changed the asteroid’s orbit around a larger asteroid, called Didymos.

[01:21.15] Data showed the strike reduced the orbital period of Dimorphos by 33 minutes.

[01:29.65] But the Hera mission seeks to closely examine Dimorphos to get more details on how the asteroid was changed in the strike by DART.

[01:42.41] Data collected by the ESA spacecraft will be used together with information gathered by NASA to develop future planetary defense plans.

[01:55.68] American astronomer Derek Richardson, from the University of Maryland, told reporters before the launch, "The more detail we can glean the better as it may be important for planning a future deflection mission should one be needed.”

[02:15.08] Officials from ESA have described the $400 million mission as a “crash scene investigation.”

[02:24.90] Hera project manager Ian Carnelli said the spacecraft was “going back to the crime site and getting all the scientific and technical information.”

[02:38.45] Hera’s trip to the asteroid is expected to take about two years.

[02:46.42] Next year, the probe plans to get a big gravitational push as it flies past Mars.

[02:53.32] It should arrive in the area around Dimorphos in December 2026.

[03:00.50] Before it was hit by DART, Dimorphos circled a larger asteroid from about 1,189 meters out.

[03:12.18] Scientists believe the orbit is now closer and that Dimorphos changed its shape.

[03:20.68] Astronomers have also found evidence the asteroid is likely moving differently.

[03:27.85] Examinations of the DART mission have suggested that rather than being a single hard rock, Dimorphos was more of a collection of rubble pieces held together by gravity.

[03:43.00] Investigators have said they believe the DART crash might have "completely deformed" the asteroid.

[03:51.76] Ignacio Tanco is the flight director for the Hera mission.

[03:57.07] He told The Associated Press that some large rocks and other materials could still be following the asteroid.

[04:06.37] This, he said, could present a damage risk to the spacecraft.

[04:12.48] “We don't really know very well the environment in which we are going to operate,” Tanco said.

[04:20.45] "But that's the whole point of the mission is to go there and find out.”

[04:26.56] Hera will be equipped with two nanosatellites.

[04:31.07] One will land on Dimorphos and capture data on the asteroid with radar.

[04:38.25] The other will study the makeup of Dimorphos from farther out.

[04:43.82] ESA and NASA will use the data to create plans for a possible asteroid strike that could cause wide destruction on Earth.

[04:55.51] Astronomers believe an asteroid wider than one kilometer – which could cause a worldwide disaster – is estimated to strike Earth about every 500,000 years.

[05:10.65] An asteroid around 140 meters – which is a little smaller than Dimorphos but could still take out a major city – is predicted to hit Earth around every 20,000 years.

[05:26.06] Currently there are no known 140-meter asteroids on a path to strike Earth.

[05:34.56] However, scientists have said only 40 percent of those space rocks are believed to have been identified.