The hydrogen in every tear
is older than the oldest stone:
it came from the beginning, here
before a single star had shone.
But carbon, threaded through your cells,
and oxygen in every breath,
were cooked in stars, in burning shells,
and scattered at the stars’ own death.
A star lives by a squeeze: it packs
four hydrogen nuclei to one
of helium, and what it lacks
in mass comes out as light: a sun.
Then, when its hydrogen runs thin,
it squeezes helium to make
the carbon in your blood and skin,
the oxygen your lungs will take.
The biggest stars go further, then,
through neon, silicon, and on
to iron, where it stops, for when
it fuses iron, the profit’s gone.
With nothing left to hold it high,
the core falls in, and in that blast
the star flings out across the sky
the elements it made, at last.
So iron, riding in your blood,
and holding oxygen you need,
was forged before the Earth was mud,
before there was a Sun, or seed.
You’re not the child of just one place:
your atoms have been round before;
you’re made of the beginning’s trace,
and stars that aren’t there any more.
A small experimentDraw yourself in elements
- Mark out a block of 10 by 10 squares. Each square is 1 per cent of your mass.
- Colour 65 squares for oxygen, 18 for carbon, 10 for hydrogen and 3 for nitrogen. Leave the last 4 for everything else: calcium, phosphorus, iron and the rest.
- Now draw a second block for atoms instead of mass. Colour about 62 squares hydrogen, 24 oxygen, 12 carbon and 1 nitrogen.
- Label each colour with where it was made: the Big Bang, or a star.
What's going on?
The two pictures look very different because hydrogen atoms are so light: they are most of your atoms but little of your weight. Your second drawing is mostly Big Bang; your first is mostly stars.