1) Telescope type
Found on
https://www.crosswordclues.com/clue/heliometer
Heliometer (from Greek sun and measure) is an instrument originally designed for measuring the variation of the sun`s diameter at different seasons of the year, but applied now to the modern form of the instrument which is capable of much wider use. The basic concept is to introduce a split element into a telescope`s optical path so as to produc.....
Found on
http://en.wikipedia.org/wiki/Heliometer
instrument for measuring apparent diameter of the sun
Found on
http://phrontistery.info/h.html
• (n.) An instrument devised originally for measuring the diameter of the sun; now employed for delicate measurements of the distance and relative direction of two stars too far apart to be easily measured in the field of view of an ordinary telescope.
Found on
http://thinkexist.com/dictionary/meaning/heliometer/
(from the article `Dollond, John`) ...Dollond learned the family trade of silk weaving. He became proficient in optics and astronomy and, in 1752, joined his eldest son, Peter, in an ... ...stellar parallax, showing the distances of the Sun and other stars from Earth, and for his early use of photography in mapping the heavens. To ... ...
Found on
http://www.britannica.com/eb/a-z/h/33
He`li·om'e·ter noun [
Helio- +
-meter : confer French
héliomètre .]
(Astron.) An instrument devised originally for measuring the diameter of the sun; now employed for delicate measurements of the distance and relative direction of two stars too far apart to be easily meas...
Found on
http://www.encyclo.co.uk/webster/H/28
The heliometer was an instrument for measuring small distances on the sky, particularly the apparent diameters of the sun and of the moon. It was invented by Bouguer in 1747, and improved by Dollond and Fraunhofer. In the common later form the object-glass of the telescope was cut into two halves, relatively movable by a screw. Each half formed a p...
Found on
http://www.probertencyclopaedia.com/browse/GH.HTM
heliometer An instrument devised originally for measuring the diameter of the sun; now employed for delicate measurements of the distance and relative direction of two stars too far apart to be easily measured in the field of view of an ordinary telescope.
Found on
http://www.wordinfo.info/words/index/info/view_unit/1302/17
noun 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
Found on
https://www.encyclo.co.uk/local/20974
No exact match found.
