They are out there
"Earth punctured by tiny cosmic missiles
By Robert Matthews, Science Correspondent
(Filed: 12/05/2002)
FORGET dangers from giant meteors: 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."
...
"Strangelets - sometimes also called strange-quark nuggets - are predicted to have many unusual properties, including a density about ten million million times greater than lead. Just a single pollen-size fragment is believed to weigh several tons."
http://www.telegraph.co.uk/news/main.jhtml?xml=%2Fnews%2F2002%2F05%2F12%2Fwnugg12.xml
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