|WikiProject Physics||(Rated Start-class, Low-importance)|
- ... [B]eryllium-10 [is] produced by cosmic ray spallation on dust in the upper atmosphere.
I'm not sure this is entirely accurate. What element acts as the parent for this spallation? If it is something between carbon and oxygen, it is possible that some of the spallation actually uses a gas as the parent and not dust. -- (T, C) 02:59, 12 May 2008 (UTC)
So... how do they know about these? They supposedly left behind their daughter elements but surely there needs to be more indication.
needs to be more specific
- An extinct radionuclide is one that scientists believe was formed by primordial processes, such as stellar nucleogenesis in the supernova(s) that contributed radioisotopes to the early solar system, about 4.6 billion years ago.