Well, no, not really, no

The oldest thing ever found on Earth has been discovered by scientists, and it is more than two billion years older than our planet.

Tiny specks of stardust, dating back seven billion years, have been uncovered in a meteorite which landed in Victoria, Australia, in 1969.

Can’t recall who did “We Are Stardust” (Hawkwind?) but they’re generally right. Every atom from iron on up is made inside a nova or supernova, no? And everything above H is made in a star? So pretty much everything must be old enough to have been through one cycle of star and boom.

17 comments on “Well, no, not really, no

  1. “we are stardust, we are golden” was a line from ‘Woodstock’ by Matthews Southern Comfort…..

  2. I suppose the claim is, more fully, “oldest thing that hasn’t been broken down and reassembled into something completely different”. In which case it’s fair enough. Meh, but fair enough

  3. “… Every atom from iron on up is made inside a nova or supernova, no?”

    Almost right. Inside a star, iron is the last stage. It’s above iron that depend on (super)novas.

  4. A Lawrence Krauss put it, the atoms in your left hand came from a different star from those in your right. It is only because stars die, that you can live.

    For wonder, it sure beats the Burning Bush….

  5. If you want to be really pedantic, all those fundamental particles have shurley been around since the big bang. Some of the protons and neutrons have been stuck together, that’s all.

  6. What will the “I didn’t come from apes!” crowd say when you tell them they came from stars? Different stars.

  7. BiGiNJ,

    But protons and neutrons aren’t fundamental particles. Neutrons certainly decay, in 10 minutes or so, if free and as beta decay (iirc) in nuclei. Quantum mechanics certainly implies that protons also decay. This has yet to be spotted or the possible half life calculated (the postulated half lives, if I am up to speed, are only because of the absence of spotting proton decay in the current and past experiments.)

  8. And everything above H is made in a star?

    Not quite, most of the He was made in the first 20 minutes after the big bang. Although starts burn H→He, not much of it ‘escapes’ because it, in turn, gets burnt into heavier elements before the star dies. Strong evidence for the big bang is that it accounts very precisely for the relative abundances of H and He (and a bit of Li).

  9. Also, actually, silicon burning can get as far as zinc (Fe -> Ni -> Zn) in the most massive cores but on in the moments before the core collapse shockwave smashes the star as it is the previous step, the nickel production, that stops the radiative energy emission.

    My various iron meteorites are iron / nickel alloys of varying fractions, rather than pure iron.

  10. Following on from Chris’s point – although there are stars that will never get above H -> He fusion because they are so small, they are also very very long lived compared even to relatively small stars such as the Sun. So all of them are still in existence (barring accidents such as being absorbed in to another star or consumed by a v heavy interstellar object).

  11. Quantum mechanics certainly implies that protons also decay. This has yet to be spotted or the possible half life calculated (the postulated half lives, if I am up to speed, are only because of the absence of spotting proton decay in the current and past experiments.)

    If protons decay, their half-life is constrained by observation to be >10^34 years. While this is many orders of magnitude greater than the current age of the universe, we can observe large numbers of protons at once (the Japs do this in their neutrino observatories).

  12. Primordial helium, deuterium and lithium were made in the first four minutes. Lithium, along with boron and beryllium, gets eaten in stars so there’s less of them than you would otherwise expect. Boron (plus D, Li, Be) is primarily made by cosmic ray spallation whacking chunks off carbon and oxygen nuclei. It’s dead easy to make carbon, nitrogen and oxygen in stars a bit more massive than the Sun. Other light elements get laddered up the periodic table by neutron or proton absorption, with even atomic-numbered elements (like C, O, Si, Ti, Ni) typically being more abundant than odd (like N, P, K, Sc, Cu). Elements up to iron/nickel/cobalt can be created in regular nuclear burning, and those above in supernovas and neutron star mergers (the r-process), but also by neutron absorption up to the drip line (the s-process). Anything above bismuth is r-process. The synthesised elements are released to the cosmos in supernovae, of course, but also from lower mass stars in planetary nebulae.

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