Instruments

Every instrument in the encyclopedia.

• Aditya Solar wind Particle Experiment (ASPEX) — A particle instrument on Aditya-L1, built by the Physical Research Laboratory, that samples the solar wind directly at the L1 point.
• AltiKa radar altimeter — A French radar altimeter on the Indo-French SARAL satellite. It was the first in space to work in the Ka band, and measures the height of the sea surface.
• Cartosat-1 stereo cameras (PAN-F and PAN-A) — Two fixed black-and-white cameras on Cartosat-1, one tilted forward and one tilted back, which photograph the same ground about 50 seconds apart to make 3D maps.
• Communication transponders (C, Ku, Ka and S band) — The radio relays that make up the main payload of INSAT, GSAT and CMS communication satellites, carrying TV, phone, internet and broadband links across India.
• INSAT-3D 19-channel sounder — An instrument on INSAT-3D, INSAT-3DR and INSAT-3DS that measures how temperature and humidity change with height in the air, the first such sounder on an Indian geostationary satellite.
• INSAT-3D six-channel imager — The six-band weather camera on INSAT-3D, INSAT-3DR and INSAT-3DS. It images the Earth disc in visible and infrared light, including at night, every half hour or less.
• Ku-band scatterometer (OSCAT) — A spinning radar that measures wind speed and direction over the ocean. ISRO has flown it on Oceansat-2, ScatSat-1 and EOS-06.
• Large Area X-ray Proportional Counter (LAXPC) — Three large gas-filled X-ray detectors on AstroSat, built by TIFR, with a combined collecting area of 8,000 cm². They time rapid changes in X-ray sources.
• LISS-I camera — The wide, coarser of the two colour cameras on India's first remote sensing satellites, IRS-1A and IRS-1B. It saw the ground in four colours at about 72.5 m detail.
• LISS-III camera — India's workhorse medium-resolution colour camera, flown on IRS-1C, IRS-1D and the three Resourcesat satellites. It sees the ground at about 23.5 m in four bands, one of them short-wave infrared.
• LISS-IV camera — The high-resolution colour camera on Resourcesat-1, 2 and 2A. It sees details of about 5.8 m in three bands and can be turned sideways to revisit a place every five days.
• MADRAS microwave imager — An Indo-French microwave imager on Megha-Tropiques that measured rain, cloud water and water vapour over the tropics until its scan mechanism failed in 2013.
• NavIC navigation payload — The radio payload on every NavIC satellite that broadcasts timing and orbit signals, from which a receiver on the ground works out its position.
• NISAR L-band radar (L-SAR) — NASA's L-band imaging radar on the joint NASA–ISRO NISAR satellite. Its 24 cm waves reach through vegetation to track tiny movements of the ground and ice.
• Ocean Colour Monitor (OCM and OCM-2) — An eight-band camera on Oceansat-1 and Oceansat-2 that measures the colour of the sea to estimate chlorophyll, plankton blooms and sediment.
• POLIX X-ray polarimeter — The main instrument on XPoSat, India's first X-ray polarimetry mission. It measures how X-rays from bright cosmic sources are polarised.
• RISAT C-band synthetic aperture radar — India's own imaging radar, built by ISRO, which sees the ground through cloud and at night. It flew on RISAT-1 and flies on EOS-04.
• RISAT-2 X-band synthetic aperture radar — An X-band imaging radar built by Israel Aerospace Industries and flown on RISAT-2, India's first radar imaging satellite in orbit, from 2009 to 2022.
• Rubidium atomic clock — The very stable clock at the heart of each NavIC satellite. Clock failures on IRNSS-1A led India to develop its own rubidium clock, first flown on NVS-01 in 2023.
• Spectro-polarimetry of HAbitable Planet Earth (SHAPE) — The one instrument on Chandrayaan-3's propulsion module. It looks back at Earth as if it were a distant planet, to learn how to recognise habitable exoplanets.
• Ultraviolet Imaging Telescope (UVIT) — Twin 38 cm telescopes on AstroSat that photograph the sky in far-ultraviolet, near-ultraviolet and visible light. Built by the Indian Institute of Astrophysics.
• Very High Resolution Radiometer (VHRR) — The weather camera that watched India's skies from geostationary orbit for three decades, on the INSAT-1 and INSAT-2 satellites, Kalpana-1 and INSAT-3A.