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> "I compare this with putting out a bucket in a rainstorm. Assuming the rainfall is constant, the amount of water that accumulates in the bucket tells you how

> "I compare this with putting out a bucket in a rainstorm. Assuming the rainfall is constant, the amount of water that accumulates in the bucket tells you how long it was exposed," said Dr Heck. does this imply that cosmic rays have been constant for half the age of the universe? or at least have a predictable decay rate? or is this just a weak analogy?

cobbzilla 7y ago
I wondered this as well. Also, even if the rate of cosmic rays has been constant, would it make sense that the impact of said rays on any body would be perfectly uniform? Wouldn't it follow a normal/gaussian distribution, such that some parts of the meteorite received a bit more cosmic rays, and some a bit less? Do the "ages" they found follow such a distribution?
- sandworm101 7y ago
  >> such that some parts of the meteorite received a bit more cosmic rays, and some a bit less? Everything in space spins, from the smallest speck of dust to entire galaxies. Put a stationary object in space, in light, and that light will start it spinning. So we would expect cosmic rays to be uniform across the surface.
  - cobbzilla 7y ago
    Thank you, I hadn't considered a spinning effect to achieve uniformity, nor that the presence of light could induce spin. Good food for thought.
  - BurningFrog 7y ago
    True, though they spin around one fixed axis. So if there is a big radiation source due "north", there should be less radiation received on the "south" side.
pacala 7y ago
The rainfall over very long periods of time is not constant. From boring relative position to the nearby star, to the activity of said star, to more exotic https://en.wikipedia.org/wiki/Gamma-ray_burst https://en.wikipedia.org/wiki/Gamma-ray_burst and God knows what else. A more honest statement: "We measured Ne-21 in meteorite minerals in higher concentration than on similar Earth minerals. We think it's caused by cosmic rays. We have no clue where the cosmic rays came from or when."

cobbzilla 7y ago

I wondered this as well. Also, even if the rate of cosmic rays has been constant, would it make sense that the impact of said rays on any body would be perfectly uniform? Wouldn't it follow a normal/gaussian distribution, such that some parts of the meteorite received a bit more cosmic rays, and some a bit less? Do the "ages" they found follow such a distribution?

sandworm101 7y ago
>> such that some parts of the meteorite received a bit more cosmic rays, and some a bit less? Everything in space spins, from the smallest speck of dust to entire galaxies. Put a stationary object in space, in light, and that light will start it spinning. So we would expect cosmic rays to be uniform across the surface.
- cobbzilla 7y ago
  Thank you, I hadn't considered a spinning effect to achieve uniformity, nor that the presence of light could induce spin. Good food for thought.
- BurningFrog 7y ago
  True, though they spin around one fixed axis. So if there is a big radiation source due "north", there should be less radiation received on the "south" side.

pacala 7y ago

The rainfall over very long periods of time is not constant. From boring relative position to the nearby star, to the activity of said star, to more exotic https://en.wikipedia.org/wiki/Gamma-ray_burst https://en.wikipedia.org/wiki/Gamma-ray_burst and God knows what else. A more honest statement: "We measured Ne-21 in meteorite minerals in higher concentration than on similar Earth minerals. We think it's caused by cosmic rays. We have no clue where the cosmic rays came from or when."