As if we didn't worry enough about big giant rocks falling from the sky, now we have teeny-tiny interstellar particles thwacking the Earth:

Earth is facing another threat from outer space. Scientists have come to the conclusion that two mysterious explosions in the 1990s were caused by bizarre cosmic missiles.

The two objects were picked up by earthquake detectors as they tore through Earth at up to 900,000 mph. According to scientists, the most plausible explanation is that they were "strangelets", clumps of matter that have so far defied detection but whose existence was posited 20 years ago.

As with all impacts, it's not just velocity, it's mass, and these things apparently don't have much. Well, compared to a lump of iron as big as Jamaica anyway.

Just when you thought the universe couldn't get any weirder...