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Not 100% sure but it seems clickbait - the title sounds like the meteorite was sitting on Earth for 4.6B years, but after reading the article, it sounds like th

Not 100% sure but it seems clickbait - the title sounds like the meteorite was sitting on Earth for 4.6B years, but after reading the article, it sounds like the rock was 4.6B years old - it likely fell to the Earth much more recently. In that case, it's not exactly remarkable - I think pretty much all the asteroids in the Solar System are 4.6B years old, because that's when they were all created.

vardump 5y ago
I'm no geologist, but I'd guess nothing can survive anywhere near 4.6B years on this planet with weather systems.
- Spare_account 5y ago
  Rocks formed on earth have been dated as old as 4 billion years https://en.m.wikipedia.org/wiki/Oldest_dated_rocks https://en.m.wikipedia.org/wiki/Oldest_dated_rocks It is unusual, though, you're right.
  - throwaway894345 5y ago
    Is it unusual because of weather systems or because of plate tectonics (rocks get pushed into the mantle and melted down and new ones emerge later)?
    - dredmorbius 5y ago
      Both, though plate tectonics are the ultimate limit. There's extraordinarily little primaeval crust extant on Earth. The Canadian Shield / Laurentine Plain is one of the largest, and is dated to 3.96 billion years, though the oldest is in Australia (Jack Hills region), with dates to 4.39 billion years via zircon crystals. (I believe that may geologically related to a region in southern Africa, with which it was originally joined, though cannot find a reference.) The ocean floor is virtually completely newer material, little of it over a 200 million years old (about 5% of Earth's total age), due to subduction. Continental crust is lighter, floats on top of the heavier oceanic crust, and has at least a chance of survival. https://www.thoughtco.com/how-old-is-the-ocean-floor-3960755 https://www.thoughtco.com/how-old-is-the-ocean-floor-3960755 https://en.wikipedia.org/wiki/Canadian_Shield https://en.wikipedia.org/wiki/Canadian_Shield https://en.wikipedia.org/wiki/Jack_Hills https://en.wikipedia.org/wiki/Jack_Hills https://www.geologyin.com/2015/11/44-billion-year-old-zircon-is-oldest.html https://www.geologyin.com/2015/11/44-billion-year-old-zircon... https://www.geologyin.com/2016/03/the-oldest-mountain-on-earth.html?m=1 https://www.geologyin.com/2016/03/the-oldest-mountain-on-ear...
      - dredmorbius 5y ago
        The oldest seafloor happens to be that of the Mediterranean, dating to about 280 million years ago. Again, that's trifling compared to the oldest land formations. The Medeterranian is all that remains of the Tethys Ocean. https://www.thoughtco.com/how-old-is-the-ocean-floor-3960755 https://www.thoughtco.com/how-old-is-the-ocean-floor-3960755
- mordnis 5y ago
  Erosion?
  - vardump 5y ago
    I was also thinking about the presumed collision with the planet that gave birth to moon. Astoundingly there are apparently still ways for some of the rocks to survive all this maelstrom. Mind boggling.
- senectus1 5y ago
  I don't think they're saying its been here for that long, just that it was formed in space before the earth was... it arrived on earth much later having spent its time touring the solar system.
mod 5y ago
" The material, which resembles loosely held-together concreted dust and particles, never underwent the violent cosmic collisions that most ancient space debris experienced as it smashed together to create the planets and moons of our solar system. It doesn’t appear to have undergone thermal metamorphism, which means it’s been sitting out there, past Mars, untouched, since before any of the planets were created meaning we have the rare opportunity to examine a piece of our primordial past." Basically, if the wording is correct, that's unusual even for meteorites.
anonAndOn 5y ago
It's briefly mentioned the astronomer tracked its arrival and was able to recover it.
- _jal 5y ago
  That is pretty great. I wonder how often that has happened. “It’s a scientific fairy-tale. First your friend tracks a meteorite, then finds it and then gifts a bit of this extra-terrestrial material to you to analyse."
dredmorbius 5y ago
This meteorite is older than dirt. It's older than rock. It's older than the hellscape that was the early Earth. The age of the Earth is accepted as 4.54 +/- 0.05 billion years (determined to within 1%, that is, within 50 million years). That's based on samples of the oldest available Earth rocks, as well as lunar material (much returned by the Apollo missions), and other meteorite finds (Antarctica turns out to be highly effective at revealing meteorites as virtually all recent terrestrial rock is several kilometers under ice). But the article does indicate that the age and primordial nature of the specimin is the principle interest: “It doesn’t appear to have undergone thermal metamorphism, which means it’s been sitting out there, past Mars, untouched, since before any of the planets were created meaning we have the rare opportunity to examine a piece of our primordial past. The one detail the article fails to provide is how the specimin was dated, though at 4.6 billion years, it's about 100 million years older than the highest accepted age of Earth itself. It would represent material from before the era of planetary formation within the early dust cloud from which our Solar System was formed.
- tablespoon 5y ago
  > “It doesn’t appear to have undergone thermal metamorphism, which means it’s been sitting out there, past Mars, untouched, since before any of the planets were created meaning we have the rare opportunity to examine a piece of our primordial past. It sounds like that's par for the course for this type of meteorite. So it's rare, but not unique: https://en.wikipedia.org/wiki/Carbonaceous_chondrite https://en.wikipedia.org/wiki/Carbonaceous_chondrite. > The carbonaceous chondrites were not exposed to higher temperatures, so that they are hardly changed by thermal processes. Some carbonaceous chondrites, such as the Allende meteorite, contain calcium-aluminum-rich inclusions (CAIs). These are compounds that emerged early from the primeval solar nebula, condensed out and represent the oldest minerals formed in the solar system .[3][4] > Some primitive carbonaceous chondrites, such as the CM chondrite Murchison, contain presolar minerals...
  - dredmorbius 5y ago
    The article is exceptionally vague on all the important bits. What you quote just goes to establishing a consequence of its age. It's not clear to me that this is the oldest meteorite found, how it was dated, how it was tracked, etc., etc. For the technical deets on dating CCs: http://www.psrd.hawaii.edu/Sept02/isotopicAges.html http://www.psrd.hawaii.edu/Sept02/isotopicAges.html
senectus1 5y ago
Is this really that rare? I mean my wedding ring on my finger right now is 1/3 Gibeon Meteorite... the Gibeon Meteorites are about 4 billion years old.

vardump 5y ago

I'm no geologist, but I'd guess nothing can survive anywhere near 4.6B years on this planet with weather systems.

Spare_account 5y ago
Rocks formed on earth have been dated as old as 4 billion years https://en.m.wikipedia.org/wiki/Oldest_dated_rocks https://en.m.wikipedia.org/wiki/Oldest_dated_rocks It is unusual, though, you're right.
- throwaway894345 5y ago
  Is it unusual because of weather systems or because of plate tectonics (rocks get pushed into the mantle and melted down and new ones emerge later)?
  - dredmorbius 5y ago
    Both, though plate tectonics are the ultimate limit. There's extraordinarily little primaeval crust extant on Earth. The Canadian Shield / Laurentine Plain is one of the largest, and is dated to 3.96 billion years, though the oldest is in Australia (Jack Hills region), with dates to 4.39 billion years via zircon crystals. (I believe that may geologically related to a region in southern Africa, with which it was originally joined, though cannot find a reference.) The ocean floor is virtually completely newer material, little of it over a 200 million years old (about 5% of Earth's total age), due to subduction. Continental crust is lighter, floats on top of the heavier oceanic crust, and has at least a chance of survival. https://www.thoughtco.com/how-old-is-the-ocean-floor-3960755 https://www.thoughtco.com/how-old-is-the-ocean-floor-3960755 https://en.wikipedia.org/wiki/Canadian_Shield https://en.wikipedia.org/wiki/Canadian_Shield https://en.wikipedia.org/wiki/Jack_Hills https://en.wikipedia.org/wiki/Jack_Hills https://www.geologyin.com/2015/11/44-billion-year-old-zircon-is-oldest.html https://www.geologyin.com/2015/11/44-billion-year-old-zircon... https://www.geologyin.com/2016/03/the-oldest-mountain-on-earth.html?m=1 https://www.geologyin.com/2016/03/the-oldest-mountain-on-ear...
    - dredmorbius 5y ago
      The oldest seafloor happens to be that of the Mediterranean, dating to about 280 million years ago. Again, that's trifling compared to the oldest land formations. The Medeterranian is all that remains of the Tethys Ocean. https://www.thoughtco.com/how-old-is-the-ocean-floor-3960755 https://www.thoughtco.com/how-old-is-the-ocean-floor-3960755
mordnis 5y ago
Erosion?
- vardump 5y ago
  I was also thinking about the presumed collision with the planet that gave birth to moon. Astoundingly there are apparently still ways for some of the rocks to survive all this maelstrom. Mind boggling.
senectus1 5y ago
I don't think they're saying its been here for that long, just that it was formed in space before the earth was... it arrived on earth much later having spent its time touring the solar system.

mod 5y ago

" The material, which resembles loosely held-together concreted dust and particles, never underwent the violent cosmic collisions that most ancient space debris experienced as it smashed together to create the planets and moons of our solar system. It doesn’t appear to have undergone thermal metamorphism, which means it’s been sitting out there, past Mars, untouched, since before any of the planets were created meaning we have the rare opportunity to examine a piece of our primordial past." Basically, if the wording is correct, that's unusual even for meteorites.

anonAndOn 5y ago

It's briefly mentioned the astronomer tracked its arrival and was able to recover it.

_jal 5y ago
That is pretty great. I wonder how often that has happened. “It’s a scientific fairy-tale. First your friend tracks a meteorite, then finds it and then gifts a bit of this extra-terrestrial material to you to analyse."

dredmorbius 5y ago

This meteorite is older than dirt. It's older than rock. It's older than the hellscape that was the early Earth. The age of the Earth is accepted as 4.54 +/- 0.05 billion years (determined to within 1%, that is, within 50 million years). That's based on samples of the oldest available Earth rocks, as well as lunar material (much returned by the Apollo missions), and other meteorite finds (Antarctica turns out to be highly effective at revealing meteorites as virtually all recent terrestrial rock is several kilometers under ice). But the article does indicate that the age and primordial nature of the specimin is the principle interest: “It doesn’t appear to have undergone thermal metamorphism, which means it’s been sitting out there, past Mars, untouched, since before any of the planets were created meaning we have the rare opportunity to examine a piece of our primordial past. The one detail the article fails to provide is how the specimin was dated, though at 4.6 billion years, it's about 100 million years older than the highest accepted age of Earth itself. It would represent material from before the era of planetary formation within the early dust cloud from which our Solar System was formed.

tablespoon 5y ago
> “It doesn’t appear to have undergone thermal metamorphism, which means it’s been sitting out there, past Mars, untouched, since before any of the planets were created meaning we have the rare opportunity to examine a piece of our primordial past. It sounds like that's par for the course for this type of meteorite. So it's rare, but not unique: https://en.wikipedia.org/wiki/Carbonaceous_chondrite https://en.wikipedia.org/wiki/Carbonaceous_chondrite. > The carbonaceous chondrites were not exposed to higher temperatures, so that they are hardly changed by thermal processes. Some carbonaceous chondrites, such as the Allende meteorite, contain calcium-aluminum-rich inclusions (CAIs). These are compounds that emerged early from the primeval solar nebula, condensed out and represent the oldest minerals formed in the solar system .[3][4] > Some primitive carbonaceous chondrites, such as the CM chondrite Murchison, contain presolar minerals...
- dredmorbius 5y ago
  The article is exceptionally vague on all the important bits. What you quote just goes to establishing a consequence of its age. It's not clear to me that this is the oldest meteorite found, how it was dated, how it was tracked, etc., etc. For the technical deets on dating CCs: http://www.psrd.hawaii.edu/Sept02/isotopicAges.html http://www.psrd.hawaii.edu/Sept02/isotopicAges.html

senectus1 5y ago

Is this really that rare? I mean my wedding ring on my finger right now is 1/3 Gibeon Meteorite... the Gibeon Meteorites are about 4 billion years old.