6 ms·

Pardon my ignorance, but as I was typing a message in a chat group linking to this page and briefly mentioning why these rocks are special, I realized that we a

by lucb1e 6y ago

Pardon my ignorance, but as I was typing a message in a chat group linking to this page and briefly mentioning why these rocks are special, I realized that we already have a ton of asteroid material on earth. I get that the outer layers will have burned in the atmosphere, but inside is still intact. Is this useful because we suspect the surface contains different materials? Or the crushing of it on impact? Or is there something else that makes this different from digging up one that came to us rather than us going to them?

yourMadness 6y ago
Asteroids on earth have been changed by the environment on earth. Part of it during entry, part of it during impact, part just lying there for long times. The Ryugu sample provides an opportunity to check our understanding of the changes that happened to asteroids on earth.
warent 6y ago
IIRC a key thing that makes it special is that it's the first time an asteroid has ever been mined
- kingofpandora 6y ago
  I'm sure the poster appreciates the achievement but the question remains whether these samples tell us something more than samples collected on earth.
- m4rtink 6y ago
  Hayabusa 1 overcame massive hurdles and then sacrificed itself to deliver it's sample 10 years ago. It was very small - less than one gram - but first. Still nice to see such a big sample mass increase as well as managing to get it without harming the main probe, which can continue to do more science. :)
JumpCrisscross 6y ago
Most of the advantage is in tech demonstration [1]. Scientifically, retrieved samples are pristine and more massive, for a single body, than terrestrial samples. Retrieval also enables sampling non-NEOs. That said, I think your intuition is correct. The scientific value of these missions pales next to their technological value. [1] https://spacenews.com/op-ed-10-reasons-why-an-asteroid-redirect-mission-is-worth-doing/ https://spacenews.com/op-ed-10-reasons-why-an-asteroid-redir...
- TeMPOraL 6y ago
  > Scientifically, retrieved samples are pristine and more massive, for a single body, than terrestrial samples. They also provide ground truth data. We know that the imaged samples 100% came from an asteroid, and a particular asteroid, whose characteristics we know from observation and other measurements. That's in contrast to terrestrial samples, for which we have to make educated guesses as to the properties of the bodies they came from. The former will be useful to cross-check and callibrate the latter.
- eb0la 6y ago
  I believe there is also a good way to prove that some models work as we expect. I mean, we have now hard evidence that an given asteroid has properties X, Y, Z - and we have mathematical (or ML) models that infer such properties from indirect measures. At least, we have evidence to validate that models or spot errors on them with ground truth.
- SiVal 6y ago
  I would prefer the description "tech development" to "tech demonstration". I never do any non-trivial tech project without learning some lessons about how I would do it differently next time. So we go out and see what's on a particular asteroid, but we also see things about the task. The next time, we try a modified approach and go see what's on a different asteroid. We build out our knowledge of what resources are already out there, and where, while building out our knowledge of how to get out there, do things, and get back. And when you get both A and B, the relative value of A vs B may be as claimed, but what really matters in the cost/benefit analysis is the value of A+B. And even the value of the science is an interesting question, because science that finds what we "already know" has some value, but not much, but science that finds what we never expected changes history. And in our estimates of scientific value, we never expect to find what we never expected.
johnny313 6y ago
Meteorite samples are far from perfect surrogates for asteroids, though. They experience extreme pressures and lose a great deal of their bulk when falling through Earth’s atmosphere. Once they land, they pick up contaminants from the terrestrial environment that are hard to distinguish from native substances. Pristine samples from an asteroid might not only answer questions about the origins of life’s chirality but also offer clues about how water ended up on Earth. One hypothesis suggests that asteroids, which contain some water, may have also seeded it onto our home planet during collisions (Science 2014, DOI: 10.1126/science.1261952). [0] [0] https://cen.acs.org/physical-chemistry/astrochemistry/tale-2-asteroid-sample-return/96/i39 https://cen.acs.org/physical-chemistry/astrochemistry/tale-2...
SmellTheGlove 6y ago
They shot a probe out into space, had it land on an asteroid, slam a slug into it to get below the surface, land on it again, and pick up rocks. In an era where the headliners are delivery and ride sharing apps, it's worth stepping back and considering this achievement for what it is. Maybe the rocks themselves aren't special, but where they came from and how we got them is a massive achievement.
- poma88 6y ago
  Nope. Not a massive achievement. Just a waste of money that could go to stop climate change.
  - TeMPOraL 6y ago
    It's a stepping stone to enable the future. There's no non-catastrophic future for humanity that doesn't involve expanding past Earth orbit. In fact, it may be entirely possible to eliminate the root cause behind climate change - economic growth - in a humane way. So the best bet is to channel it in ways that aren't destructive to Earth's biosphere. Asteroid mining is a part of that, and this achievement is a stepping stone in that direction.
  - Ma8ee 6y ago
    There are neither economical or technological hurdles that stop us from ending the release of greenhouse gases within a few years. It is only political will. Stopping climate change is too late since it is already happening and it won’t be easy to get rid of the CO2 that we already released.
  - crubier 6y ago
    That’s an argument I can accept when talking about not spending trillions in wars and defense, but no when spending 1/10000th of that amount into the future of our species and something all our ancestors could only dream of: seeing alien worlds.
  - t-writescode 6y ago
    Today has been a day of hatred on Hacker News. First it was a person naysaying in the sex toy automation thread and now it’s here. The sphere of knowledge and the sphere of usefulness expand in all directions. Sometimes usefulness expands in entertainment and pleasure (no one complains about Blizzard employees or Valve employees making games), sometimes they expand into cancer research, global warming research or, yes, in this case, space travel and extraterrestrial discovery. There are billions of people on this planet and billions of them have the potential to be scientists or engineers in some area of the multi-dimensional spheres of all human knowledge and use. If humanity must be seen as a hive mind, then it still can parallel process with, again, billions of people and hundreds of millions of scientists.
anonAndOn 6y ago
Don't organic molecules break down when getting cooked in the atmosphere? Perhaps they'll find some chemistry that doesn't normally survive the fall to Earth.
johannes1234321 6y ago
Contrary to random pieces falling onto earth they are from a specific astroid and not impacted by earth atmosphere (which burns those stones quite a bit) Thus they potentially reveal more details and allow comparison with planets and other objects, which might help to identify the origin of the astroid and in turn be a piece in the big story how our solar system came together.
m3at 6y ago
To quote the Hayabusa2 team directly (http://www.hayabusa2.jaxa.jp/en/topics/20201204_ts3/ http://www.hayabusa2.jaxa.jp/en/topics/20201204_ts3/) : > You might therefore wonder if we should instead analyse meteorites. However, meteorites consist of the material that is left over after re-entry through the atmosphere and their structure, along with easily volatile substances, have been lost. They will also be contaminated with substances from the Earth. On the other hand, samples from the asteroids are brought back to Earth in the same condition as they were in space, with the “re-entry capsule” protecting the sample through the atmosphere and landing.
dingaling 6y ago
> I realized that we already have a ton of asteroid material on earth. The quantity isn't as high as you might expect. Most meteor flux is from cometary dust, not asteroids. The Geminids and Taurids are asteroid in origin but no meteorites have been traced to those showers. Once the atmosphere and oceans take care of the majority, only about 10 meteorites of asteroid origin are recoverable each year.

by lucb1e 6y ago

yourMadness 6y ago

Asteroids on earth have been changed by the environment on earth. Part of it during entry, part of it during impact, part just lying there for long times. The Ryugu sample provides an opportunity to check our understanding of the changes that happened to asteroids on earth.

warent 6y ago

IIRC a key thing that makes it special is that it's the first time an asteroid has ever been mined

kingofpandora 6y ago
I'm sure the poster appreciates the achievement but the question remains whether these samples tell us something more than samples collected on earth.
m4rtink 6y ago
Hayabusa 1 overcame massive hurdles and then sacrificed itself to deliver it's sample 10 years ago. It was very small - less than one gram - but first. Still nice to see such a big sample mass increase as well as managing to get it without harming the main probe, which can continue to do more science. :)

JumpCrisscross 6y ago

Most of the advantage is in tech demonstration [1]. Scientifically, retrieved samples are pristine and more massive, for a single body, than terrestrial samples. Retrieval also enables sampling non-NEOs. That said, I think your intuition is correct. The scientific value of these missions pales next to their technological value. [1] https://spacenews.com/op-ed-10-reasons-why-an-asteroid-redirect-mission-is-worth-doing/ https://spacenews.com/op-ed-10-reasons-why-an-asteroid-redir...

TeMPOraL 6y ago
> Scientifically, retrieved samples are pristine and more massive, for a single body, than terrestrial samples. They also provide ground truth data. We know that the imaged samples 100% came from an asteroid, and a particular asteroid, whose characteristics we know from observation and other measurements. That's in contrast to terrestrial samples, for which we have to make educated guesses as to the properties of the bodies they came from. The former will be useful to cross-check and callibrate the latter.
eb0la 6y ago
I believe there is also a good way to prove that some models work as we expect. I mean, we have now hard evidence that an given asteroid has properties X, Y, Z - and we have mathematical (or ML) models that infer such properties from indirect measures. At least, we have evidence to validate that models or spot errors on them with ground truth.
SiVal 6y ago
I would prefer the description "tech development" to "tech demonstration". I never do any non-trivial tech project without learning some lessons about how I would do it differently next time. So we go out and see what's on a particular asteroid, but we also see things about the task. The next time, we try a modified approach and go see what's on a different asteroid. We build out our knowledge of what resources are already out there, and where, while building out our knowledge of how to get out there, do things, and get back. And when you get both A and B, the relative value of A vs B may be as claimed, but what really matters in the cost/benefit analysis is the value of A+B. And even the value of the science is an interesting question, because science that finds what we "already know" has some value, but not much, but science that finds what we never expected changes history. And in our estimates of scientific value, we never expect to find what we never expected.

johnny313 6y ago

Meteorite samples are far from perfect surrogates for asteroids, though. They experience extreme pressures and lose a great deal of their bulk when falling through Earth’s atmosphere. Once they land, they pick up contaminants from the terrestrial environment that are hard to distinguish from native substances. Pristine samples from an asteroid might not only answer questions about the origins of life’s chirality but also offer clues about how water ended up on Earth. One hypothesis suggests that asteroids, which contain some water, may have also seeded it onto our home planet during collisions (Science 2014, DOI: 10.1126/science.1261952). [0] [0] https://cen.acs.org/physical-chemistry/astrochemistry/tale-2-asteroid-sample-return/96/i39 https://cen.acs.org/physical-chemistry/astrochemistry/tale-2...

SmellTheGlove 6y ago

They shot a probe out into space, had it land on an asteroid, slam a slug into it to get below the surface, land on it again, and pick up rocks. In an era where the headliners are delivery and ride sharing apps, it's worth stepping back and considering this achievement for what it is. Maybe the rocks themselves aren't special, but where they came from and how we got them is a massive achievement.

poma88 6y ago
Nope. Not a massive achievement. Just a waste of money that could go to stop climate change.
- TeMPOraL 6y ago
  It's a stepping stone to enable the future. There's no non-catastrophic future for humanity that doesn't involve expanding past Earth orbit. In fact, it may be entirely possible to eliminate the root cause behind climate change - economic growth - in a humane way. So the best bet is to channel it in ways that aren't destructive to Earth's biosphere. Asteroid mining is a part of that, and this achievement is a stepping stone in that direction.
- Ma8ee 6y ago
  There are neither economical or technological hurdles that stop us from ending the release of greenhouse gases within a few years. It is only political will. Stopping climate change is too late since it is already happening and it won’t be easy to get rid of the CO2 that we already released.
- crubier 6y ago
  That’s an argument I can accept when talking about not spending trillions in wars and defense, but no when spending 1/10000th of that amount into the future of our species and something all our ancestors could only dream of: seeing alien worlds.
- t-writescode 6y ago
  Today has been a day of hatred on Hacker News. First it was a person naysaying in the sex toy automation thread and now it’s here. The sphere of knowledge and the sphere of usefulness expand in all directions. Sometimes usefulness expands in entertainment and pleasure (no one complains about Blizzard employees or Valve employees making games), sometimes they expand into cancer research, global warming research or, yes, in this case, space travel and extraterrestrial discovery. There are billions of people on this planet and billions of them have the potential to be scientists or engineers in some area of the multi-dimensional spheres of all human knowledge and use. If humanity must be seen as a hive mind, then it still can parallel process with, again, billions of people and hundreds of millions of scientists.

anonAndOn 6y ago

Don't organic molecules break down when getting cooked in the atmosphere? Perhaps they'll find some chemistry that doesn't normally survive the fall to Earth.

johannes1234321 6y ago

Contrary to random pieces falling onto earth they are from a specific astroid and not impacted by earth atmosphere (which burns those stones quite a bit) Thus they potentially reveal more details and allow comparison with planets and other objects, which might help to identify the origin of the astroid and in turn be a piece in the big story how our solar system came together.

m3at 6y ago

To quote the Hayabusa2 team directly (http://www.hayabusa2.jaxa.jp/en/topics/20201204_ts3/ http://www.hayabusa2.jaxa.jp/en/topics/20201204_ts3/) : > You might therefore wonder if we should instead analyse meteorites. However, meteorites consist of the material that is left over after re-entry through the atmosphere and their structure, along with easily volatile substances, have been lost. They will also be contaminated with substances from the Earth. On the other hand, samples from the asteroids are brought back to Earth in the same condition as they were in space, with the “re-entry capsule” protecting the sample through the atmosphere and landing.

dingaling 6y ago

> I realized that we already have a ton of asteroid material on earth. The quantity isn't as high as you might expect. Most meteor flux is from cometary dust, not asteroids. The Geminids and Taurids are asteroid in origin but no meteorites have been traced to those showers. Once the atmosphere and oceans take care of the majority, only about 10 meteorites of asteroid origin are recoverable each year.