1. :en:Non-achromatic objective
1. :en:Nonius (device)
1. :en:Noyes Armillary Sphere
1. :en:Nuclear Compton Telescope
1. :en:Null detector
1. :en:Ocean-bottom seismometer
1. :en:Octant (instrument)
1. :en:Odin-OSIRIS
1. :en:Ohana project
1. :en:Optical correlator
1. :en:Optical instrument
1. :en:Optical mount
1. :en:Optical Payload for Lasercomm Science
1. :en:Optical power meter
1. :en:Optical square
1. :en:Optical System for Imaging and low Resolution Integrated Spectroscopy
1. :en:Optical telescope
1. :en:Orbiting Carbon Observatory 3
1. :en:Orrery
1. :en:Otto Struve Telescope
1. :en:Ozone monitoring instrument
1. :en:Palomar Testbed Interferometer
1. :en:Parallactic instrument of Kapteyn
1. :en:Particle mass analyser
1. :en:Passemant astronomical clock
1. :en:Paul Marmet
1. :en:Pedro Nunes
1. :en:Periscope lens
1. :en:Perspective machine
1. :en:Phase Shift Interferometry
1. :en:Pierre Vernier
1. :en:Pierre-Louis Guinand
1. :en:Plane table
1. :en:Planetary Fourier Spectrometer
1. :en:Planisphere
1. :en:Plasma Instrument for Magnetic Sounding
1. :en:Plasma wave instrument
1. :en:Plasma Wave Subsystem
1. :en:PLate OPtimizer
1. :en:Plough (instrument)
1. :en:Pluto Energetic Particle Spectrometer Science Investigation
1. :en:Polar alignment
1. :en:Polarimeter
1. :en:POlarization Emission of Millimeter Activity at the Sun
1. :en:Polarograph
1. :en:Post Instrument
1. :en:Post office box (electricity)
1. :en:PQube
1. :en:Probe tip
1. :en:Pseudoscope
1. :en:Purple Crow Lidar
1. :en:Pyramid wavefront sensor
1. :en:Quadrans Vetus
1. :en:Quadrant (instrument)
1. :en:Qubic experiment
1. :en:Radar for Europa Assessment and Sounding: Ocean to Near-surface
1. :en:Radio latino
1. :en:Radio science subsystem
1. :en:Ralph (New Horizons)
1. :en:Raman Laser Spectrometer
1. :en:Ramsden surveying instruments
1. :en:Rapid Eye Mount telescope
1. :en:Rectangulus
1. :en:Reentry Breakup Recorder
1. :en:Reflecting instrument
1. :en:Reticle
1. :en:REX (New Horizons)
1. :en:Reynolds and Branson
1. :en:Rheoscope
1. :en:Rhinoscope
1. :en:Rock Abrasion Tool
1. :en:Ronchi test
1. :en:Rotating furnace
1. :en:Rotation and Interior Structure Experiment
1. :en:Rotational modulation collimator
1. :en:RTT-150
1. :en:Ruling engine
1. :en:Samuel Knibb
1. :en:Santucci's Armillary Sphere
1. :en:SBUV/2
1. :en:Scale of chords
1. :en:Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals
1. :en:Schiefspiegler
1. :en:Schmidt corrector plate
1. :en:Schmidt telescope
1. :en:Schmidt–Väisälä camera
1. :en:Scientific equipment optician
1. :en:Scintillating bolometer
1. :en:Secondary mirror
1. :en:Seismic array
1. :en:Seismic Experiment for Interior Structure
1. :en:Sextant (astronomy)
1. :en:Shadow square
1. :en:Shuttle Radar Topography Mission
1. :en:Signs Of LIfe Detector
1. :en:Simon Plössl
1. :en:Sine quadrant
1. :en:Sira (notified body)
1. :en:SkyMapper
1. :en:SkyScout
1. :en:Slide rule scale
1. :en:Slit lamp
1. :en:Slooh
1. :en:Solar telescope
1. :en:Solar X-ray Imager
1. :en:SOPHIE échelle spectrograph
1. :en:Spaceborne Imaging Radar
1. :en:Spacecraft Atmosphere Monitor
1. :en:Special sensor microwave/imager
1. :en:Spectroheliograph
1. :en:Spectrohelioscope
1. :en:Spectrometer Telescope for Imaging X-rays
1. :en:Spectronic 20
1. :en:SPEX (astronomy)
1. :en:Spider (polarimeter)
1. :en:Spin casting (mirrors)
1. :en:SSMIS
1. :en:Stanford Dish
1. :en:Stauroscope
1. :en:Stereoautograph
1. :en:Stonyhurst disks
1. :en:Strainmeter
1. :en:String galvanometer
1. :en:Subaru Telescope
1. :en:SuperNova Early Warning System
1. :en:Surface Dust Analyser
1. :en:Sutton armillary
1. :en:SWAP (instrument)
1. :en:SWAP (New Horizons)
1. :en:SWEAP
1. :en:TAGSAM
1. :en:Taqi ad-Din Muhammad ibn Ma'ruf
1. :en:Telecompressor
1. :en:Telescope mount
1. :en:Tellurion
1. :en:Temperature and Winds for InSight
1. :en:The Porter Garden Telescope
1. :en:Thermal and Evolved Gas Analyzer
1. :en:Thermal Emission Spectrometer
1. :en:Thermo galvanometer
1. :en:Tiltmeter
1. :en:Timeline of telescope technology
1. :en:Timeline of telescopes, observatories, and observing technology
1. :en:Tiny Ionospheric Photometer
1. :en:Torquetum
1. :en:Total Ozone Mapping Spectrometer
1. :en:Total station
1. :en:Tpoint
1. :en:Transient Array Radio Telescope
1. :en:Transversal (instrument making)
1. :en:Triquetrum (astronomy)
1. :en:Tropospheric Emissions: Monitoring of Pollution
1. :en:Unistellar
1. :en:Upside down goggles
1. :en:Urey instrument
1. :en:UVS (Juno)
1. :en:Venetia Burney Student Dust Counter
1. :en:Venus Emissivity Mapper
1. :en:Verona astrolabe
1. :en:Versorium
1. :en:Visible Multi Object Spectrograph
1. :en:Volvelle
1. :en:W. Watson and Son
1. :en:Warkworth Radio Astronomical Observatory
1. :en:Warkworth Radio Telescope
1. :en:Wavefront curvature sensor
1. :en:Wavefront sensor
1. :en:Waves (Juno)
1. :en:Westphal balance
1. :en:Wimshurst machine
1. :en:WISDOM (radar)
1. :en:Wood–Anderson seismometer
1. :en:XyloTron
1. :en:Yantraraja
1. :en:Zeeman slower