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Wired.com's For the Second Time Ever, an Asteroid Sample Returns to Earth says that "the sample return capsule from Hayabusa2" will land "under parachute in the Australian outback" "early on (this) Sunday morning".

Australian astronomers have extensive experience reconstructing the trajectory of a fiery objet through the upper atmosphere and then modeling it's descent to the surface, predicting the best place to look for it, then looking for it and finding it. For more on that see answer to How long between the moment a meteor is first visible and the moment a meteorite hits the ground? and Wikipedia's Desert_Fireball_Network.

Question: Is that how Hayabusa2's return capsule will be tracked? Is that why reentry is scheduled for early on Sunday morning when it's dark enough to visualize reentry but will soon be light enough for visual location on the surface?

Or is that all just a coincidence and tracking will be done via spacecraft telemetry before entry begins and "Outback radar" stations once it does?


The Wired article ends:

You can catch a livestream of the fiery finale of Hayabusa2’s main mission on Japan Aerospace Exploration Agency’s YouTube channel. The capsule is scheduled to begin its atmospheric entry at around 12:30 pm ET on Saturday (or 2:30 am on Sunday in Japan) and will land about 15 minutes later.

NOTE: There are several livestream events on JAXA's site! The capsule separation even is scheduled to start about six hours after this question was originally posted for example. Check it out!


Desert Fireball Network related:

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    $\begingroup$ I'm not sure if it's exactly what you want but the Hayabusa2 Twitter had a tweet about how they'll find the capsule when it lands twitter.com/haya2e_jaxa/status/1334785498003296257 If this does answer your question feel free to add it as a formal answer. $\endgroup$ – Wiggo the Wookie Dec 4 '20 at 22:16
  • $\begingroup$ @WiggotheWookie Thanks for the information, someone may do so. I can't believe that the fireball network won't at least try to track and extrapolate it's descent at least as an exercise, but we may have to wait until later to read about it. The parachute obviously makes extrapolation a lot harder than for a falling rock, but if for some reason the beacon doesn't work there'd better be some backup plan! $\endgroup$ – uhoh Dec 4 '20 at 22:21
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    $\begingroup$ Australian ABC has a quote from a member of the fireball network team here abc.net.au/news/2020-12-05/… but unsure if there is a more complete version of that interview. $\endgroup$ – GremlinWranger Dec 5 '20 at 1:07
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There's a good description of the planned landing procedure in the news item, Japan's Hayabusa2 space capsule to fall back to Earth after six-year asteroid mission.

Essentially human observers on the ground at Woomera and in the air, combined with radar tracking and the use of a tracking beacon will be used to track and locate the returned capsule.

As the capsule descends towards Earth at supersonic speeds, its trajectory will be tracked by teams of scientists spread across hundreds of kilometres on the ground and in the air.

As the sole international observer, Australian scientist Trevor Ireland will be on board the helicopter tasked with spotting the capsule somewhere in an area tens of kilometres wide.

"We should know pretty much where it is as it comes down," said Professor Ireland of the Australian National University, who was also on the science team for the Hayabusa1 mission.

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As the capsule slows down in the Earth's atmosphere, the heatshield around it will light up as a fireball for about 40 to 50 seconds above Coober Pedy, 400 kilometres north of Woomera.

As the capsule slows down in the Earth's atmosphere, the heatshield around it will light up as a fireball for about 40 to 50 seconds above Coober Pedy, 400 kilometres north of Woomera.

"Last time it was very spectacular because the spacecraft came in with it," Professor Ireland said.

"This time we don't want it to be quite so spectacular, we just want to see that nice red glow of the space capsule coming in."

Once the capsule slows down enough, it will deploy a drag parachute and then a second main parachute.

Scientists, including four teams from the Desert Fireball Network at Curtin University, will track the trajectory of the capsule as it streaks across the sky.

"The Desert Fireball Network team will be putting out cameras all the way along the Stuart Highway to take pictures of this bright shooting star," said team leader Ellie Sansom, who is currently in Coober Pedy.

The Desert Fireball Network has also partnered with a group of Japanese researchers who cannot be in Australia due to the COVID-19 pandemic, and is putting out instruments from them that listen to the sonic boom and detect any ground shaking.

Back in Woomera, more than 70 Japanese scientists will track the descent using radar, Professor Ireland said.

"The radar guys will get a much longer view of it as it comes in because once the parachute opens up they'll have a bigger object to look at," he said.

A radio beacon on the capsule will help the Japanese scientists refine the position.

"The radio signals were within a few hundred metres last time," Professor Ireland said.

Meanwhile, NASA scientists flying on two aeroplanes will observe how material blows off the heat shield of the capsule as it descends.

"That last 10 kilometres is the big issue as it's coming down, once it gets into our weather systems."

If the weather isn't kind, it will make the retrieval a little trickier too.

"If it's not a very nice day, they'll try to get it contained very quickly so it doesn't get covered in dust or rain."

Once the capsule lands, a team including Professor Ireland will head out to search for it.

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    $\begingroup$ I've just run across this Desert Fireball Network page for the event and you may want add some of this to your answer: dfn.gfo.rocks/hayabusa.html $\endgroup$ – uhoh Dec 7 '20 at 3:08
  • $\begingroup$ Can't wait to see some of the awesome observations! but yes we used optical, seismic, infrasound, and some other instruments that the Japanese researchers wanted to use. Sorry, I cannot give more details, I am back in Perth and didn't participate in the recovery as we were limited by covid :( $\endgroup$ – Patrick Dec 7 '20 at 5:39
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    $\begingroup$ @uhoh: thanks for the Desert Fireball Network link. I'll get to that soon, .... $\endgroup$ – Fred Dec 8 '20 at 2:46

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