Mars Orbiter Mission (MOM) spacecraft is orbiting Mars in a highly elliptical orbit characterized by nearest point to Mars (periapsis) at around 300 km and farthest point (apoapsis) at ~71,000 km. The inclination of orbit with respect to the equatorial plane of Mars is ~150 degree, as intended. In this orbit, the spacecraft takes ~73 hrs to go round the Mars once. A brief description of the instruments is given below.

Mars Colour Camera (MCC)

Mars Colour Camera (MCC) is an electro-optical sensor imaging surface of Mars in three colours, varying spatial resolution between ~20 m to ~4 km in 16 different exposure modes, depending on its position in orbital plane and illumination conditions. The MCC payload provides data in true colors of Mars covering Red, Green and Blue as Bayer pattern. Important science objectives of MCC include studying morphology of landforms, wind streaks, dynamic processes such as dust storms in different seasons. Technical specifications of MCC are provided in Annexure-1.

Thermal Infrared Imaging Spectrometer (TIS)

Thermal Infrared Imaging Spectrometer (TIS) instrument is aimed to observe thermal emission from Mars surface to detect its temperature and hot spot regions or hydrothermal vents on Martian surface. The TIS is designed to observe emitted infrared radiation from Martian environment in 7–13 µm region of electromagnetic spectrum using a micro bolometer device. Brief specifications of the TIS are provided in Annexure 2.

Methane Sensor for Mars (MSM)

Methane Sensor for Mars (MSM) is a differential radiometer based on Fabry–Perot Etalon filters to measure columnar methane (CH4) in the Martian atmosphere at several parts per billion (ppb) levels. This differential signal gives a measure of columnar amount of CH4. The possible finding of methane in Martian atmosphere will provide clues about the presence of life on Mars. A brief specification of the MSM instrument is provided in Annexure 3.

Lyman Alpha Photometer (LAP)

Lyman Alpha Photometer (LAP) is essentially a compact far-ultraviolet photometer capable of providing deuterium to hydrogen (D/H) abundance ratio of Martian exosphere from spacecraft observations. Comparison of the present and initial D/H ratio, estimated from observations of the D/H ratio in comets and asteroids, which are believed to be sources of Martian water should allow us to calculate the amount of hydrogen and, therefore, the water that has been lost over planet’s lifetime. Primary scientific objective of the LAP instrument is to determine D/H isotope ratio of Martian upper atmosphere from the ratio of the measured Lyman-alpha intensities. The observations would enable us to i) generate spatial and temporal profiles of hydrogen and deuterium Lyman-alpha intensities, ii) study of deuterium-enrichment in the upper atmosphere and iii) estimate of the water escape/loss rate. Brief specifications of the LAP instrument are provided in Annexure 4.

Mars Exospheric Neutral Composition Analyser (MENCA)

The MENCA instrument is meant for in situ study of the composition of the Martian neutral exosphere. Taking advantage of the highly elliptical orbit of the MOM spacecraft, MENCA data can be used to derive information on the radial distribution and composition of the Martian neutral exosphere. Brief specifications of the MENCA instrument are provided in Annexure 5.