[HN Gopher] Surprising Phosphate Finding in NASA's Osiris-Rex As...
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Surprising Phosphate Finding in NASA's Osiris-Rex Asteroid Sample
Author : kumarm
Score : 89 points
Date : 2024-06-28 00:25 UTC (3 days ago)
(HTM) web link (www.nasa.gov)
(TXT) w3m dump (www.nasa.gov)
| mjevans wrote:
| What if the origin of Osiris-Rex (Asteroid) is higher energy
| debris from a major impact to Earth during the early stages of
| organic life on the planet. Wasn't one theory (?) for our moon's
| creation such an impact and then a large mass splitting off to
| form the moon? I could easily imagine smaller bodies with higher
| local concentrations of energy being ejected from such an event.
| actionfromafar wrote:
| I don't think there could have been life on Earth before the
| creation of the moon.
| malux85 wrote:
| Why not? (I don't know this field)
| admissionsguy wrote:
| The Moon forming impact (4.5 Gyr) occurred ~100 million
| years after Earth's formation. The earliest solid grain
| comes from another ~100 million years after that (4.4 Gyr).
| The earliest signs of life (4.1 Gyr) are from ~300 million
| years after the earliest grain. Does not seem implausible
| that life could have arisen during the first 100 million
| years as well. We know very little about that era since the
| impact liquified the whole surface.
| actionfromafar wrote:
| Wouldn't the (pre Moon) Earth have been pretty hot after
| formation and probably no water either?
| admissionsguy wrote:
| There's been some research from my alma mater that it
| might have had water even that early [1]. I haven't seen
| good data on the estimated temperature during this time
| (it was hot certainly, the question would be how
| frequently were there pockets where hyperthermophiles
| would be able survive). I like this paper's approach [2]
| - they end up with a small chance of life before the
| impact.
|
| [1] https://archive.is/NZwpJ
|
| [2]
| https://www.liebertpub.com/doi/pdf/10.1089/ast.2005.5.154
| malux85 wrote:
| Ah ok, didn't know the moon formed that quickly, thank
| you for your detailed answer, very interesting :)
| shiroiushi wrote:
| Perhaps it came from Earth when the Chuxhulub asteroid struck?
|
| It's really too bad we weren't able to get a sample from the
| ['Oumuamua](https://en.wikipedia.org/wiki/%CA%BBOumuamua)
| asteroid when it flew through the system. It was definitely an
| extra-solar asteroid, so it would have had material completely
| unrelated to our own system's formation and history.
| alenrozac wrote:
| There will be more like that, but we need to get better at
| identifying them. Just like with exoplanets.
| pavel_lishin wrote:
| Not just identifying them, but also being able to catch
| them in time. They're coming in at solar escape velocities,
| and going out with same - and the odds of everything being
| aligned in such a way that we can take several years to do
| gravity assists are incredibly low.
| mathsmath wrote:
| I wonder if a one-way trip with an impactor would be
| useful. It would at least be easier than a roundtrip
| journey to and from solar escape velocity.
|
| Also, it seems like the space base weapons treaty is
| being ignored now (https://spacenews.com/russia-vetoes-u-
| n-resolution-on-nuclea...,
| https://www.npr.org/2024/05/30/nx-s1-4975741/what-to-
| know-ru...). I wonder if there is an opportunity to do
| some science with space-based lasers and spectroscopy.
| The energy would be small, but then again we can learn a
| lot just from the off-gassing created by the sun's
| photons as well.
| pavel_lishin wrote:
| Oh yeah, I don't think we're anywhere near "sample
| return" capability for an extra-solar object.
|
| I doubt we're even near "impactor" capability, tbh. I
| think our best bet might be "catch up with something in
| the Oort somewhere around 2070, if we see something
| coming a decade ahead of time".
| mathsmath wrote:
| Never underestimate the ability of humans to throw
| something really hard ;)
|
| I actually think if the object was on the right
| trajectory and we had enough time, that you could pretty
| much park an impactor in its path. You could probably do
| a lot of science based on the spectra of the resulting
| cloud.
|
| I agree that gently landing and return a sample with that
| much delta V is out of our reach at this point. _Maybe_
| with enough shielding, you could park a second sample
| return vehicle in the path of debris.
| adolph wrote:
| > odds of everything being aligned in such a way that we
| can take several years to do gravity assists are
| incredibly low.
|
| _Project Lyra develops concepts for reaching
| interstellar objects such as 1I / 'Oumuamua and 2I /
| Borisov with a spacecraft, based on near-term
| technologies._ [0]
|
| _Several technology options are outlined, ranging from a
| close solar Oberth Maneuver using chemical propulsion,
| and the more advanced options of solar and laser sails._
| [1]
|
| 0. https://i4is.org/what-we-do/technical/project-lyra/
|
| 1. https://arxiv.org/abs/1711.03155
| XorNot wrote:
| It occurs to me since survivability isn't a problem for
| an unmanned probe, that a "cold" nuclear thermal engine
| vehicle could be used as a loitering interceptor: get it
| a solar orbit, and leave it till you see a target, then
| accelerate up to extra-solar escape velocity.
|
| It solves the disposal problem neatly, since the probe
| and reactor are both leaving the solar system forever
| afterwards.
| wumms wrote:
| From [0]:
|
| > Bennu's basic mineralogy and chemical nature would have been
| established during the first 10 million years of the Solar
| System's formation [...]
|
| > Bennu probably began in the inner asteroid belt as a fragment
| from a larger body with a diameter of 100 km. Simulations
| suggest a 70% chance it came from the Polana family and a 30%
| chance it derived from the Eulalia family. Impactors on
| boulders of Bennu indicate that Bennu has been in near Earth
| orbit (separated from the main asteroid belt) for 1-2.5 million
| years.
|
| [0]
| https://en.wikipedia.org/wiki/101955_Bennu#Origin_and_evolut...
| pfdietz wrote:
| Rocks on Earth (and the Moon) are distinguished by being on a
| specific line on the oxygen isotope plot, the SMOW (Standard
| Mean Ocean Water) line. This may reflect a large, homogenizing
| event in the early history of the Earth (like a giant impact
| that formed the Moon).
|
| The realization that meteorites come from multiple different
| parent bodies is that they are distributed widely, not all on
| one line on this plot. Bennu, like primitive meteorites,
| appears to be off the terrestrial line.
|
| https://ntrs.nasa.gov/api/citations/20240000340/downloads/Fr...
| pfdietz wrote:
| Small bodies in the early solar system were likely heated by
| short lived radionuclides, which were injected into the gas cloud
| that formed the solar system by a nearby supernova explosion.
| Remnants of the decay of such isotopes have been found in
| primitive grains in meteorites.
|
| This heating would have kept the bodies warm enough for liquid
| water to exist in their interiors for a periods of perhaps some
| millions of years. The total volume of these could have been
| quite large, and offers the interesting possibility that life
| originated in our Solar System in one of these bodies, not on
| Earth itself. If so, this could explain why life appeared on
| Earth so early: if OoL tends to occur in such bodies, it either
| happens early (before they freeze up) or it doesn't occur at all.
| This would counter the inference that because life originated
| early on Earth, OoL must be a high probability event.
|
| The presence of phosphate minerals is mildly promising as
| phosphate is somewhat rare and is biologically essential in
| nucleic acids, ATP, and some cell membranes.
| lawlessone wrote:
| Maybe i lack imagination but i don't see how rock formed in a
| deep ocean could survive relatively unchanged by the kind of
| impact that would launch it out into space.
|
| Your idea fixes that for me.
| gradus_ad wrote:
| For life to emerge in the span of a few million years within
| liquid interiors of early solar system bodies, life would need
| to be a relatively high probability event. I don't think this
| changes the probability of life calculus vs the traditional
| life emerging on Earth story.
| pavel_lishin wrote:
| If there were enough of these warm, water-bearing bodies,
| then the probability could be low and still result in early
| life formation, right?
| pfdietz wrote:
| Especially if the "enough" is "enough around any star,
| anywhere". The a priori probability of it happening around
| any particular star need not be high. And "anywhere" can be
| something extremely broad, as in "on any branch of a
| universal Many Worlds wave function".
| gradus_ad wrote:
| Yes but the window of time during which these bodies could
| have contained liquid water was very narrow, so there would
| have needed to be a very high number of such bodies to
| support the low probability of life hypothesis
| pfdietz wrote:
| No, that's wrong. You're ignoring that if it didn't happen,
| we wouldn't be here to see the result. Observer selection
| bias. The less common OoL is, the more biased our observation
| is.
| gradus_ad wrote:
| Observer selection bias is independent of the earth vs non
| earth body question, it's an issue regardless.
| pfdietz wrote:
| Yes, it also demolishes the naive Copernican argument
| that because life is on Earth, it must be common.
|
| The more subtle argument was that because life originated
| _early_ on Earth, OoL must be a high probability event.
| But that argument implicitly assumes the probability of
| OoL is relatively constant with time, so it wouldn 't be
| biased to occur early. OoL on small planetesimals is
| naturally biased to occur early, due to decay of those
| short lived radioisotopes. After the planetesimals freeze
| OoL there doesn't seem possible.
| pvaldes wrote:
| Ok. What is an Ool?
| blagund wrote:
| Watch the movie Caveman to find out! Ool anyone?
| erikig wrote:
| In this context "Origins of life"
| pvaldes wrote:
| I would suggest replacing 'Ool' by 'origin of life' or
| even better just 'life' then. Is much easier to
| understand and it just adds one character to the term
| superposeur wrote:
| I would think this point would be obvious, but apparently
| not given the many frustrating discussions I've had with
| smart people on the topic. (Maybe there is a subtlety I'm
| not appreciating?) It's a relief to see the good solid
| sense in all your comments on this thread.
| marcosdumay wrote:
| Unless life can only appear on that kind of environment for
| some reason.
|
| It's hard to imagine any such reason. Honestly I don't think
| there's any to find. But it's still an open question.
| jajko wrote:
| Tons of assumptions, we can go hyperbolic onto almost anything
| if you lean into it hard enough.
|
| Unless there is some solid proof that life happened on Earth
| well before larger bodies of water formed, I'd go for the most
| obvious theory - biggest stable body of water around and that
| is our pretty unique planet.
| pfdietz wrote:
| The current mass of asteroids is estimated to be about the
| same as the current mass of Earth's oceans. The mass of
| asteroids early in the solar system was likely much larger.
| So I don't see why one would necessarily prefer Earth to be
| the OoL location.
| svachalek wrote:
| I think the current contender for biggest body of water in
| the solar system is Europa.
| andrewflnr wrote:
| It's still a heck of a coincidence that one of these life-
| bearing asteroids hit Earth at exactly the time life could
| survive here. This becomes more likely if a lot of asteroids
| develop life, pushing it back into high-probability. Though
| it's still more susceptible to view bias, since you could have
| lots of stellar systems where life freezes before it makes it
| to a planet.
|
| Either way, the notion of asteroids being more hospitable to
| OoL than planets, with their complex and varied environments
| and chemistry, would require quite the extraordinary evidence
| in my book.
| pfdietz wrote:
| Since we don't have a great idea how life originated,
| preferring Earth to these small bodies seems to me to be mere
| prejudice. This is especially the case when early Venus and
| Mars were likely more habitable than early Earth.
|
| It wouldn't be necessary for a life bearing asteroid to hit
| Earth in order to seed Earth. Rather, a collision of a life-
| bearing asteroid (perhaps since frozen) in space would create
| a large number of fragments, any one of which could seed
| Earth. This strikes me as the most certain part of the
| scenario. After all, this is how meteorites are created.
| andrewflnr wrote:
| > preferring Earth to these small bodies seems to me to be
| mere prejudice.
|
| I really don't think it is. For any favorable condition you
| might find in asteroids, early planets can probably match
| it, and a bunch of other possible conditions besides, with
| the additional benefit of not requiring a stage where the
| nascent life has to survive an impact at orbital speeds,
| subsequent flight through cold irradiated vacuum, and then
| re-entry through a dense planetary atmosphere. I'm not
| saying it's impossible, but I'm saying it needs a lot more
| evidence to take it seriously.
| prewett wrote:
| > These rocks have retained their original state, having neither
| melted nor resolidified since their inception
|
| How are they able to tell that?
| malfist wrote:
| I don't pretend to know in this case, but sometimes you can
| tell by the lattice, see
| https://en.m.wikipedia.org/wiki/Widmanst%C3%A4tten_pattern
|
| The only way a widmanst pattern forms is by slow cooling of the
| iron over millions of years. Check out the wiki section on why
| it can't be reproduced in a lab
| pyinstallwoes wrote:
| It is interesting it's triangular
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