BEHOLD! Japan's Hayabusa2 probe left human imprints on ASTEROID SAND
- Reference: 1585211470
- News link: https://www.theregister.co.uk/2020/03/26/hayabusa2_small_carry_on_impactor_study_findings/
- Source link:
Hayabusa2 unloaded the SCI with the intention of creating a crater we could study to figure out what asteroids are made of.
The analysis of the SCI's impact, [2]published in Science , suggests a rather sandy environment.
[3]
Images of the Hayabusa2's SCI impact on asteroid Ryugu. Click to enlarge. Arakawa et al
Scientists drew that conclusion despite the SCI making a semi-circular crater, a shape attributed to the presence of a large boulder near the impact site. That rock, named Okamoto, was unmoved by the SCI. Another smaller rock, the five-metre boulder named Iijima, was moved by several metres. The Japan Aerospace Exploration Agency's [4]explainer says: "A small pit was also formed close to the impact site, implying that Ryugu may have a layered structure, with a harder layer containing the pit overlaid with a fluffier surface material."
Comet 67P's cute rubber duck shape perfect for causing eruptions [5]READ MORE
Fluffiness recurs in the formal paper in which scientists have tried to interpret the patterns of material left behind by the impact – "ejecta" in crater-boffin language.
The SCI appears to have created ejecta but it didn't travel far beyond the rim. But it also created more ejecta than expected and a bigger crater than was predicted.
Which is where things get tricky: the paper's authors have tried to model the behaviour of different materials when whacked by the SCI under Ryugu's low gravity, and then to interpret the materials on the asteroid's surface.
Their conclusion? Ryugu is probably covered in a layer of something rather loosely held together, perhaps rather like sand. And if Ryugu is sandy, its surface material is probably also only about nine million years old, which perhaps coincides with whatever incident caused it to leave the main asteroid belt and settle in its current near-Earth orbit where it's less likely to experience collisions that disturb the sand.
We'll know more soon because later this year the probe will send a sample of Ryugu-stuff to Earth. Assuming there's anyone left to find and analyse the payload. ®
[1] https://www.theregister.co.uk/2019/04/05/hayabusa_2_beresheet/
[2] https://science.sciencemag.org/content/early/2020/03/18/science.aaz1701
[3] https://regmedia.co.uk/2020/03/26/hayabusa2_ryugu_japan2.jpg
[4] http://www.hayabusa2.jaxa.jp/en/topics/20200320_science/
[5] https://www.theregister.co.uk/2018/05/24/comet_67ps_cute_rubber_duck_shape_causes_bright_jets_to_shoot_out_every_morning/
Nothing that a healthy supply of bog rolls won't solve.
Threat
Have you seen Daniel Espinosa's movie [1]"Life" ?
Although a bit far fetched in many aspects, it left me wondering about just how much thought, peer review and control is actually going into the handling of whatever is brought back to Earth from space.
For what we know, it could well end up being more than just asteriod sand.
O.
[1] http://www.imdb.com/title/tt5442430/
Leaving our mark
I'm reminded of the snail that crawled across the Cenotaph. When he got to the other side he looked back proudly at his snail trail and said "Look, I've left my mark".
Yes, we're explorers, but our pride at putting our machinery in the beauty of space can seem misplaced.
Re: Leaving our mark
ego = 1/knowledge.
That mark was made to gain knowledge so it is very little to do with pride or the slime of ego.
Thanks for the embiggenment
Impressive to see just how long it takes (i.e. just how low the gravity is) for the ejecta to think about settling.
@Dunstan V - I'm not convinced that the leaving of the mark was the primary cause, but merely a byproduct of a scientific measurement. If one takes the view that one should never make a mark anywhere, no matter how remote nor how 'unchanged', one would never get out of bed (and one's bed would not be in a house to keep the rain off).
Footprints?
Oh well. I was hoping to hear that they'd actually put little moulded human feet on the legs of a space probe, and landed it somewhere... :-)
I hope they are careful with the samples from Ryugu, they could contain an alien virus that would threaten all human life on Earth.