No. 133: JAN-FEB 2001
No problem, says R. Frost of the University of Melbourne, "They could be in orbit around Invisible Stars! (Ref. 2)
If we can have Missing Matter, we suppose that Invisible Stars are not as ridiculous as they sound. It is postulated that Invisible Stars are composed of Mirror Matter, a new construct of astronomers who are desperately trying to explain their burgeoning files of celestial anomalies. Mirror Matter is strange "stuff." It interacts with Ordinary Matter only through gravity, it doesn't emit light. It is palpable but invisible. (This sounds weird, but no weirder than quantum mechanics!)
Foot also pointed out that stars composed of Ordinary Matter may be orbited by Mirror-Matter planets. Expanding along these lines, whole star systems could be 100% Mirror Matter, and we'd never see them at all.
How about Mirror-Matter asteroids and meteors zipping around our solar system -- invisible but palpable and threatening? As a matter of fact, it has been speculated that the still-mysterious Tunguska Event of 1908 (lots of energy but no crater) was an encounter with a Mirror-Matter meteor. (Ref. 3)
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