noun

• 1

  (also altazimuth mount, mounting)

  Astronomy
  A telescope mounting that moves in azimuth (about a vertical axis) and in altitude (about a horizontal axis).

  ‘The Dobsonian design is the most popular type of altazimuth mounting used on astronomical telescopes.’

  Compare with equatorial mount

  More example sentences

  • ‘Scopes with altazimuth mounts are easy to set up and use, and require no special expertise to use properly.’
  • ‘Even with this disadvantage, the altazimuth mounting will be the primary mounting for very large telescopes to be constructed in the future.’
  • ‘While the altitude axis of an altazimuth mount may bend, the bending is constant and can be compensated by realignment of the tube or optics.’
  • ‘However, in recent years computerized altazimuth mounts have appeared which use motors to automatically compensate for the sky's motion, though these are generally a great deal more expensive.’

  1. 1.1A telescope on an altazimuth mounting.
     ‘Of course, everything below about 80 degrees altitude was very easy to find; all altazimuth telescopes have this quirk.’
     More example sentences

     • ‘A lot of my variables are near bright stars or distinctive star patterns; thus easy to find with my noncomputerized altazimuth telescope or binoculars.’
     • ‘All are fully-steerable altazimuth telescopes capable of pointing and tracking over zenith angles from 1 to 60 degrees.’
     • ‘Another highly entertaining presentation was by Dennis di Cicco of Sky and Telescope magazine as he described his construction of a 16-inch ‘sidewalk’ altazimuth telescope.’
     • ‘Since altazimuth telescope mounts usually have a limit in their ability to track high elevation passes through culmination, especially at near-zenith transits because of the large azimuth swings required, the mount can start falling behind.’

• 2A surveying instrument for measuring vertical and horizontal angles, resembling a theodolite but larger and more precise.

  More example sentences

  • ‘This is an altazimuth theodolite of an improved pattern now used on the Ordnance Survey.’