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{%type%} Definitions

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Short "hint"

An instrument used to measure the angular separation of two stars that are too far apart to be included in the field of view of an ordinary telescope.

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Usage examples (24)
  • But there is one instrument of great value, the heliometer, which is not used at Greenwich.
  • A heliometer is the most accurate astronomical instrument for relative measurements of position, as a transit circle is the most accurate for absolute determinations.
  • Joseph Fraunhofer perfected the refracting telescope, as Herschel had perfected the reflector, and invented a wonderfully accurate "heliometer," or sun-measurer.
  • Munich, who constructed a magnificent heliometer for the Observatory at
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