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No. 23: Sep-Oct 1982

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Zoom Lens In The Atmosphere

June 29, 1981. South Atlantic Ocean.

At 1700 GMT, the master and third officer of the Rockhampton Star observed a vessel at a distance of 6 nautical miles. Its appearance was normal for that distance. At 12 n.m., however, it was magnified four times over what it should have been for that distance. At 16 n.m., the apparent magnification was eight. The interesting aspects of this phenomenon are:

  1. Increasing magnification with distance; and
  2. The magnified image was perfect in two dimensions and not distorted along the vertical axis as is usually the case in abnormal refraction.

(White, A.H.; "Abnormal Refraction," Marine Observer, 52:80, 1982.)

Comment. What kind of stable atmospheric lens can do this?

Reference. Phenomena like that above are termed "telescopic mirages." These are cataloged at GEM2 in Rare Halos, Mirages. For a description of this book, visit: here.

From Science Frontiers #23, SEP-OCT 1982. � 1982-2000 William R. Corliss