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| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Chandrayaan-2 | 2/6 | https://en.wikipedia.org/wiki/Chandrayaan-2 | reference | science, encyclopedia | 2026-05-05T12:59:52.302451+00:00 | kb-cron |
The Chandrayaan-2 orbiter is orbiting the Moon on a polar orbit at an altitude of 100 km (62 mi). It carries eight scientific instruments; two of which are improved versions of those flown on Chandrayaan-1. The approximate launch mass was 2,379 kg (5,245 lb). The Orbiter High Resolution Camera (OHRC) conducted high-resolution observations of the landing site prior to separation of the lander from the orbiter. The orbiter's structure was manufactured by Hindustan Aeronautics Limited and delivered to the ISRO Satellite Centre on 22 June 2015.
Dimensions: 3.2 × 5.8 × 2.2 m Gross lift-off mass: 2,379 kg (5,245 lb) Propellant mass: 1,697 kg (3,741 lb) Dry mass: 682 kg (1,504 lb) Power generation capacity: 1000 watts Mission duration: ~ 7.5 years, extended from the planned 1 year owing to the precise launch and mission management, in lunar orbit
=== Vikram lander ===
The mission's lander is called Vikram (Sanskrit: विक्रम, romanized: Vikrama, lit. 'Valour' ) named after cosmic ray scientist Vikram Sarabhai (1919–1971), who is widely regarded as the founder of the Indian space programme. The Vikram lander detached from the orbiter and descended to a low lunar orbit of 30 km × 100 km (19 mi × 62 mi) using its 800 N (180 lbf) liquid main engines. After checking all of its on-board systems it attempted a soft landing that would have deployed the rover, and performed scientific activities for approximately 14 Earth days. Vikram crash-landed during this attempt. The combined mass of the lander and rover was approximately 1,471 kg (3,243 lb). The preliminary configuration study of the lander was completed in 2013 by the Space Applications Centre (SAC) in Ahmedabad. The lander's propulsion system consisted of eight 58 N (13 lbf) thrusters for attitude control and five 800 N (180 lbf) liquid main engines derived from ISRO's 440 N (99 lbf) liquid apogee motor. Initially, the lander design employed four main throttle-able liquid engines, but a centrally mounted fixed-thrust engine was added to handle new requirements of having to orbit the Moon before landing. The additional engine was expected to mitigate upward draft of lunar dust during the soft landing. The four throttle-able engines of lander were capable of throttling between range of 40 to 100 percent incrementally in steps of 20%. Vikram was designed to safely land on slopes up to 12°. Some associated technologies include :
A high resolution camera, Laser Altimeter (LASA) Lander Hazard Detection Avoidance Camera (LHDAC) Lander Position Detection Camera (LPDC) Lander Horizontal Velocity Camera (LHVC) 800 N throttleable liquid main engine Attitude thrusters Ka-band radio altimeters Laser Inertial Reference and Accelerometer Package (LIRAP) and the software needed to run these components. Engineering models of the lander began undergoing ground and aerial tests in late October 2016, in Challakere in the Chitradurga district of Karnataka. ISRO created roughly 10 craters on the surface to help assess the ability of the lander's sensors to select a landing site.
Dimensions: 2.54 m × 2 m × 1.2 m (8 ft 4 in × 6 ft 7 in × 3 ft 11 in) Gross lift-off mass: 1,471 kg (3,243 lb) Propellant mass: 845 kg (1,863 lb) Dry mass: 626 kg (1,380 lb) Power generation capability: 650 watts Mission duration: ≤14 days (one lunar day)
=== Pragyan rover ===
The mission's rover was called Pragyan (Sanskrit: Prajñāna, lit. 'Wisdom' ) ) with a mass of 27 kg (60 lb), and would have operated on solar power. The rover was to move on six wheels, traversing 500 m (1,600 ft) on the lunar surface at the rate of 1 cm (0.39 in) per second, perform on-site analyses and send the data to the lander, which would have relayed it to the Mission Control on the Earth. For navigation, the rover would have used :
Stereoscopic Camera-based 3D Vision : Two 1 megapixel, monochromatic navcams in front of the rover to provide the ground control team a 3D view of the surrounding terrain, and help in path-planning by generating a digital elevation model of the terrain. IIT Kanpur contributed to the development of the subsystems for light-based map generation and motion planning for the rover. Control and Motor Dynamics : The rover has a rocker-bogie suspension system and six wheels, each driven by independent brushless DC electric motors. Steering is accomplished by differential speed of the wheels or skid steering. The expected operating time of Pragyan rover was one lunar day, or ~14 Earth days, as its electronics were not designed to endure the frigid lunar night. However, its power system has a solar-powered sleep/wake-up cycle implemented, which could have resulted in longer service time than planned. Two aft wheels of the rover had the ISRO logo and the State Emblem of India embossed on them to leave behind patterned tracks on the lunar surface.
Dimensions: 0.9 × 0.75 × 0.85 m Power: 50 watts Travel speed: 1 cm/sec Mission duration: ~14 Earth days (one lunar day)
=== Telemetry, tracking, and command (TT&C) === During various phases of launch and spacecraft operations of Chandrayaan-2 mission, the TT&C support was provided by ISRO Telemetry, Tracking and Command Network (ISTRAC), Indian Deep Space Network (IDSN), NASA Deep Space Network and National Institute for Space Research's (INPE) ground stations located in Alcântara and Cuiabá.
== Science payload ==
ISRO selected eight scientific instruments for the orbiter, four for the lander, and two for the rover. While it was initially reported that NASA and European Space Agency (ESA) would participate in the mission by providing some scientific instruments for the orbiter, ISRO in 2010 had clarified that due to weight restrictions it will not be carrying foreign payloads on the mission. However, in an update a month before launch, an agreement between NASA and ISRO was signed to include a small laser retroreflector from NASA to the lander's payload to measure the distance between the satellites above and the microreflector on the lunar surface.
=== Orbiter ===
The orbiter has several scientific payloads.