Europe's Hera probe to launch Oct. 7 to inspect asteroid NASA smacked in 2022
'We're very excited to go back and see what it looks like.'
The European Space Agency's Hera spacecraft is loaded into a jet in early September 2024 for the trip from Germany to Florida ahead of its planned Oct. 7 liftoff.(Image credit: ESA)
Europe's highly anticipated Hera mission to catalog the wreckage of the asteroid Dimorphos has arrived at its Florida launch site for final checks ahead of its planned liftoff early next month.
The main Hera spacecraft and its two partner cubesats, named Milani and Juventas, are set to launch atop a SpaceX Falcon 9 rocket on Oct. 7 at 10:52 a.m. EDT (1452 GMT) from Cape Canaveral Space Force Station in Florida. They'll arrive at Dimorphos in late 2026, on a mission to study the aftermath of NASA's planetary defense test, which intentionally smashed a spacecraft into the asteroid in September 2022, shortening its orbit by 33 minutes and permanently altering its shape.
"We're very excited to go back and see what it looks like," Patrick Michel, Hera's principal investigator, said at the Europlanet Science Congress on Friday (Sept. 13) in Berlin.
Hera will assess the size and depth of the crater on Dimorphos created by NASA's DART (Double Asteroid Redirection Test) spacecraft, and determine whether the impact did indeed reshape the rubble-pile asteroid, as early simulations indicate. Once deployed, the two cubesats will for the first time assess Dimorphos' internal structure, surface minerals as well as gravity, data that will help scientists correctly reproduce the asteroid's final structure in their computer models, Michel said at the conference. Such models will then inform future planetary defense missions that similarly aim to deflect asteroids headed toward Earth.
Hera and its two cubesats arrived at their launch site in Florida in early September following a transatlantic flight from Germany, with a stop in Ireland. The mission's launch window opens on Oct. 7 and closes on Oct. 27, according to the European Space Agency (ESA).
Hera has a date with Mars in March next year; it will receive a gravity boost from the Red Planet to put it on course toward Dimorphos. During the maneuver, Hera will swing past the Mars moon Deimos and test onboard science instruments and its main camera.
"It gives us another chance to calibrate our instruments and potentially to make some scientific discoveries," Michael Kuppers, who is Hera's project scientist at ESA, said of the Mars flyby in a previous statement.
If all goes to plan, the spacecraft will arrive at Dimorphos in late 2026 and inch closer to the asteroid's surface through repeated flybys until it ends up less than 0.6 miles (1 kilometer) away, Kuppers said at the conference.
The mission is expected to gather at least six months of close-up observations of the asteroid, which at 525 feet (160 meters) wide is about the size of the Great Pyramid of Giza in Egypt. Dimorphos' surface will be more visible at that point than it was in the immediate aftermath of the DART collision; the rocks and dust blasted into space by the smashup have since floated away, likely on their way to spark meteor showers on Mars and possibly Earth.
Hera's images of Dimorphos will also help determine whether DART's crash indeed knocked the asteroid out of alignment such that it now wobbles back and forth, as scientists have suggested.
"Dimorphos might also be 'tumbling,' meaning that we may have caused it to rotate chaotically and unpredictably," Derek Richardson, a professor of astronomy at the University of Maryland and a DART investigation working group lead, said last month in a university statement. "One of our biggest questions now is if Dimorphos is stable enough for spacecraft to land and install more research equipment on it."
That answer might arrive at the end of Hera's mission, when its two cubesats Milani and Juventas will attempt to land on Dimorphos. Hera itself might land on Didymos, Dimorphos' larger companion — both spacecraft orbit a common center of mass — although the specifics of end-of-mission scenarios are still under discussion, Kuppers said on Friday.
Quelle: SC
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Update: 6.10.2024
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A spaceship punched an asteroid — we’re about to learn what came next
ESA’s Hera mission will study a rock called Dimorphos, which was blasted by NASA, to work out how successful that approach was in deflecting its course.
The Hera mission and its twin CubeSats will study the asteroids Dimorphos and Didymos (artist’s impression). Credit: ESA
The European Space Agency (ESA) is set to launch a mission that will assess how effective humanity could be in protecting Earth from an asteroid impact. Called Hera, the mission will visit a rock blasted by a NASA spacecraft in 2022 to analyse the effects of the deflection effort.
“It seems like we hit it hard enough and we reshaped it,” says Harrison Agrusa, a Hera team member and a planetary scientist at the Côte d’Azur Observatory (OCA) in Nice, France.
Hera is set to launch no earlier than 7 October on a SpaceX Falcon 9 rocket from Cape Canaveral in Florida, although the lift-off might be delayed while SpaceX investigates an issue with its launch vehicle. The solar-powered spacecraft, which is the size of a small car, will take two years to reach its target, the binary asteroid system of Didymos and Dimorphos between Earth and Mars, arriving in late 2026.
The €363-million (US$398-million) mission is a follow-up to NASA’s DART, the Double Asteroid Redirection Test. In September 2022, the similarly sized DART spacecraft slammed into Dimorphos, the smaller of the two asteroids at 160 metres across. That impact shortened the period of the asteroid’s nearly 12-hour orbit around Didymos by 33 minutes (see ‘Impact assessment’). That’s strong evidence that space agencies could, in future, use a similar approach to deflect an asteroid on course with Earth, say researchers. No such asteroid is currently known.
Delayed mission
Hera was supposed to have been present at Dimorphos for the DART impact to gather data on the experiment in real-time. But ESA cancelled the mission in 2016 before reviving it in 2019, meaning it would now arrive four years after DART. That means comparisons of Dimorphos’s form before and after impact are more difficult.
“It would have been better to have the full characteristics, but we can live with that,” says Patrick Michel, a planetary scientist at the OCA and Hera’s mission lead. “Fortunately, the outcome of the impact will [still] be there.”
Source: ESA/NASA/A. F. Cheng et al. Nature616, 457–460 (2023).
DART hit the asteroid at 22,000 kilometres per hour, and sent nearly 1,000 tonnes of material into space, including boulders the size of buses. Remote observations suggest that it formed a crater about 50 metres across, the width of a football field, but the true size won’t be known until Hera arrives. “It’s a big divot a third of the width of the body,” says Dawn Graninger, a physicist at Johns Hopkins University Applied Physics Laboratory (JHUAPL) in Laurel, Maryland, and a Hera scientist.
Hera will slowly sidle up to the system when it arrives, positioning itself on a path around both rocks. “This is the first rendezvous with a binary asteroid,” says Michel. It will then study the asteroids for six months using cameras and an infrared imager, gradually lowering its altitude above them from 30 kilometres down to one kilometre.
“Hera is a detective, like Colombo,” says Michel. “It’s going back to the crime scene and telling us what happened, and why.”
Reshaped asteroid
Studying the system will give us an unprecedented understanding of these two-rock systems, says Alice Quillen, an astronomer at the University of Rochester in New York. About 15% of asteroids are thought to be binaries. “One of the mysteries about binary asteroids is they’re predicted to fall apart really quickly,” she says, because of radiation pressure from the Sun. A slight wobble in Dimorphos’s orbit might explain how it stays gravitationally bound to Didymos.
The impact might also have caused Dimorphos to tumble as it orbits Didymos. Previously, it had been tidally locked, with the same face always pointing towards its larger companion, as the Moon does Earth. But DART might have caused its axis to spin chaotically, possibly even head over heels, something Agrusa predicted before impact. “We think that this prediction might have come true,” he says.
Dimorphos as seen by the DART spacecraft 11 seconds before impact.Credit: NASA/Johns Hopkins APL
Differences in the position of boulders on Dimorphos’s surface in Hera’s images compared with DART’s pictures could also reveal how much the rock has changed.
The mission will “tie-off some of the loose ends” of the deflection experiment, says Andy Rivkin, a planetary scientist at JHUAPL who led the DART mission and is now working on Hera.
About two months into the mission, Hera will deploy two small CubeSats, called Juventas and Milani, that will encircle the asteroid pair. Measuring the distance between all three spacecraft will help scientists to work out Dimorphos’s gravitational pull and thus its mass, a crucial piece of information in understanding asteroid deflection. If the mass is low, “then maybe we deflected it so easily because it was light”, says Michel. But if the mass is high, it suggests that DART’s approach was even more effective at pushing the asteroid off course.
Both CubeSats will later attempt to land on Dimorphos, providing richer information on its gravity and composition — and take images from the surface.
Hera might also touch down on Didymos as its final resting place, ending this grand escapade. “Altogether it’s a rehearsal for if we did have to intercept something” heading for Earth, says Rivkin.
Quelle: nature
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Update: 7.10.2024
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Hera mission headed to asteroid as part of planetary defense test to launch Monday
In 2022, a NASA spacecraft intentionally crashed into an asteroid to test a planetary defense system — could the impact redirect the asteroid? That was the question, and it worked. Now the European Space Agency, together with the NASA and SpaceX, is sending another spacecraft back to conduct more tests on the nudged asteroid.
At 10:52 a.m. Monday, SpaceX will launch the Hera spacecraft for ESA from Cape Canaveral Launch Complex 40. The destination of this surveying spacecraft is the same asteroid system NASA previously paid a visit to with its DART mission.
In 2021, the NASA DART (Double Asteroid Redirection Test) mission was launched atop a Falcon 9 rocket from Vandenburg Space Force Base in California. A planetary defense test by John Hopkins Applied Physics Laboratory, along with many NASA centers, the DART spacecraft traveled approximately 6,835,000 miles from Earth to a near-Earth asteroid system — which consists of the asteroid Didymos and its orbiting moonlet known as Dimorphos.
The goal: crash the spacecraft into moonlet Dimorphos and measure the impact on its orbit around Didymos. On September 26, 2022, the DART spacecraft, referred to as a kinetic impactor, smashed into the small asteroid at approximately four miles per second. All in the name of testing the kinetic impact method as a means to redirect an asteroid, should one ever be a threat to Earth, the mission worked. Measurements from the ground showed the impact shortened Didymos' orbit by approximately 32 minutes.
However, scientists wondered about long term impact. That's where Hera comes in.
Led by ESA, with the support of a team of 12 NASA scientists, Hera will pay a visit to Didymos and Dimorphos to get an up close look at the results.
It's important to note: there is currently no threat to Earth, and these tests are purely planetary defense experiments.
What is the Hera spacecraft?
ESA and NASA describe the Hera spacecraft as "box-shaped base on a central tube and adapter cone." The spacecraft has two solar panel wings to assist with power, which measure around 13 square meters when deployed. It will navigate to its destination with assistance of NavCams alongside a star- and sun-tracker.
Hera weighs a whopping 2,676 pounds when fully fueled before launch.
According to NASA, Hera is brining along two Asteroid Framing Cameras (AFCs), the Hyperscout-H spectral imager, a Thermal InfraRed Imager (TIRI), and the two CubeSats (known as Juvenitas and Milani).
When will Hera arrive at Didymos/Dimorphos?
Hera will arrive at Didymos and Dimorphos in late 2026. Once arriving, it will make observations that can't be made from Earth − including measuring the mass of both bodies and any changes DART's impact may have caused. This includes close flybys, observations of the DART impact site, and finally landing on the surface of Didymos.
The observations from Hera could reveal if the kinetic impact method is a valid method for planetary defense.
SpaceX Falcon 9 second stage issue
After launching NASA Crew-9 to the International Space Station last week, the SpaceX Falcon 9 rocket's upper stage experienced an abnormal deorbit burn. While no harm was done to the trajectory of the Dragon spacecraft and the crew safely reached the station, this caused the upper stage to land outside of the intended area.
Sunday morning, the FAA issued the following statement:
"The SpaceX Falcon 9 vehicle is authorized to return to flight only for the planned Hera mission scheduled to launch on Oct. 7 from Cape Canaveral Space Force Station in Florida. The FAA has determined that the absence of a second stage reentry for this mission adequately mitigates the primary risk to the public in the event of a reoccurrence of the mishap experienced with the Crew-9 mission.
Safety will drive the timeline for the FAA to complete its review of SpaceX’s Crew-9 mishap investigation report and when the agency will authorize Falcon 9 to return to regular operations."
While the FAA continues the investigation, NASA claims it has no impact to their upcoming missions, including Europa Clipper, which is set to launch no earlier than October 10.
