Scientists from a Texas University claim to have discovered positive proof that tiny cosmic missiles known as strangelets occasionally hit the Earth, passing right through it as if it were naught but a block of butter. Strangelets are no larger than a pollen grain, but are so dense they can rip through the Earth and exit it again within seconds.

The existence of strangelets was first hypothesised 20 years ago, but not much is understood about them as yet, despite ongoing experiments. They are believed to have been formed during the Big Bang and inside very dense stars, and are created by quarks, which are subatomic particles found in protons and neutrons.