Chandrayaan-3

Indian lunar lander mission

  • Lander
  • Rover
OperatorISROCOSPAR ID2023-098A Edit this at WikidataSATCAT no.57320WebsiteOfficial websiteMission duration9 months and 13 days (elapsed) (PM)
  • Propulsion module: ≤ 3 to 6 months (planned) 8 months and 22 days (elapsed) (since orbit insertion)
  • Vikram lander: ≤ 14 days (planned)
    12 days (final) (since landing)
  • Pragyan rover: ≤ 14 days (planned)
    12 days (final) (since deployment)
Spacecraft propertiesBusChandrayaanManufacturerISROLaunch mass3900 kg (8600 lb)[1]Payload massPropulsion Module: 2148 kg (4736 lb)
Lander Module (Vikram): 1726 kg (3806 lb)
Rover (Pragyan) 26 kg (57 lb)
Total: 3900 kg (8600 lb)PowerPropulsion Module: 758 W
Lander Module: 738 W (WS with Bias)
Rover: 50 W Start of missionLaunch date14 July 2023 (2023-07-14), 14:35:17 IST (09:05:17 UTC)[2]RocketLVM3 M4Launch siteSatish Dhawan Space CentreContractorISRO Moon orbiterOrbital insertion5 August 2023Orbital parametersPeriselene altitude153 km (95 mi)Aposelene altitude163 km (101 mi)Moon landerSpacecraft componentVikram landerLanding date23 August 2023 (2023-08-23), 18:03 IST (12:33 UTC)[3]Return launch3 September 2023 (2023-09-03)[3]Landing siteStatio Shiv Shakti (Shiv Shakti Point)[4] 69°22′23″S 32°19′08″E / 69.373°S 32.319°E / -69.373; 32.319[5]
(between Manzinus C and Simpelius N craters)[6]Moon roverLanding date23 August 2023Distance driven101.4 m (333 ft)[7]Moon landerSpacecraft componentVikram landerLanding date3 September 2023 (2023-09-03)[3]Landing site40 cm (16 in) away from Statio Shiv Shakti (Shiv Shakti Point)[8]
(between Manzinus C and Simpelius N craters)[9]Flyby of MoonSpacecraft componentPropulsion moduleClosest approach7 November 2023
Mission insignia
Chandrayaan programme
← Chandrayaan-2
 

Chandrayaan-3 (/ˌʌndrəˈjɑːn/ CHUN-drə-YAHN) is the third mission in the Chandrayaan programme, a series of lunar-exploration missions developed by the Indian Space Research Organisation (ISRO).[10] The mission consists of a Vikram lunar lander and a Pragyan lunar rover similar to those launched aboard Chandrayaan-2 in 2019, as well as a propulsion module that carried the spacecraft from Earth orbit to lunar orbit.

Chandrayaan-3 was launched from Satish Dhawan Space Centre on 14 July 2023. The spacecraft entered lunar orbit on 5 August, and became the 1st lander to touch down near the lunar south pole[11] on 23 August at 18:03 IST (12:33 UTC), making India the fourth country to successfully land on the Moon, and at 69°S, the southernmost lunar landing, until IM-1 landed further southwards in Malapert A crater on 22 February 2024.[12][note 1] The lander was not built to withstand the cold temperatures of the lunar night, and sunset over the landing site ended the surface mission twelve days after landing.[16][17] The propulsion module, still operational, transited back to a high Earth orbit from lunar orbit on 22 November 2023 for continued scientific observations of Earth.[18]

History

On 22 July 2019, ISRO launched Chandrayaan-2 on board a Launch Vehicle Mark-3 (LVM3) launch vehicle consisting of an orbiter, a lander and a rover.[19] The lander was scheduled to touch down on the lunar surface on 6 September 2019 to deploy the Pragyan rover. The lander lost contact with mission control, deviated from its intended trajectory while attempting to land near the lunar south pole, and crashed.[20][21]

The lunar south pole region holds particular interest for scientific exploration. Studies show large amounts of ice there. The ice could contain solid-state compounds that would normally melt under warmer conditions elsewhere on the Moon—compounds which could provide insight into lunar, Earth, and Solar System history. Mountains and craters create unpredictable lighting that protect the ice from melting, but they also make landing there a challenging undertaking for scientific probes. For future crewed missions and outposts, the ice could also be a source of oxygen, of drinking water as well as of fuel due to its hydrogen content.[22][23]

The European Space Tracking network (ESTRACK), operated by the European Space Agency (ESA), and Deep Space Network operated by Jet Propulsion Laboratory (JPL) of NASA are supporting the mission.[24] Under a new cross-support arrangement, ESA tracking support could be provided for upcoming ISRO missions such as those of India's first human spaceflight programme, Gaganyaan, and the Aditya-L1 solar research mission. In return, future ESA missions will receive similar support from ISRO's own tracking stations.[25]

For the first time on the lunar surface, a laser beam from NASA's Lunar Reconnaissance Orbiter was broadcast on 12 December 2023, and it was reflected back by a tiny NASA retroreflector on board the Vikram lander. The purpose of the experiment was to determine the retroreflector's surface location from the moon's orbit. The Chandrayaan-3 lander's Laser Retroreflector Array (LRA) instrument began acting as a location marker close to the lunar south pole. Through multinational cooperation, the LRA was housed on the Vikram lander. On a hemispherical support framework, it consists of eight corner-cube retroreflectors. This array enables any orbiting spacecraft equipped with appropriate instruments to use lasers ranging from different directions. The 20 gram passive optical instrument is intended to survive for several decades on the lunar surface.[26]

Objectives

ISRO's mission objectives for the Chandrayaan-3 mission are:

  1. Engineering and implementing a lander to land safely and softly on the surface of the Moon.
  2. Observing and demonstrating the rover's driving capabilities on the Moon.
  3. Conducting and observing experiments on the materials available on the lunar surface to better understand the composition of the Moon.[27]

Spacecraft

Design

Chandrayaan-3 comprises three main components: a propulsion module, lander module, and rover.

  • Chandrayaan-3 encapsulated within LVM3's payload fairing
    Chandrayaan-3 encapsulated within LVM3's payload fairing
  • Chandrayaan-3 integrated components
    Chandrayaan-3 integrated components

Propulsion module

The propulsion module carried the lander and rover configuration to a 100-kilometre (62 mi) lunar orbit. It was a box-like structure with a large solar panel mounted on one side and a cylindrical mounting structure for the lander (the Intermodular Adapter Cone) on top.[28][29]

A few months after the conclusion of the lander portion of the mission, ISRO officials said that the propulsion module was equipped with two radioisotope heating units (RHU), designed and developed by BARC (Bhabha Atomic Research Centre). RHUs keep spacecraft at their operational temperature using the decay of radioactive material, to generate electricity to power heaters. It is thought[by whom?] that national security reasons delayed the disclosure to the media. Chandrayaan-3 project director P Veeramuthuvel said ISRO may use nuclear resources to maintain instruments in future rovers. ISRO officials later said the RHUs could not be installed on Chandrayaan-3's Vikram lander and Pragyan rover because it would have increased their mass. This reduced their maximum lifespan to 14 Earth days, or 1 lunar day.[30][31][32] On 4 December 2023, ISRO reported that the propulsion module was reinserted into an orbit around the Earth.[18] The primary objective of the reinsertion was to allow Earth observations by spectral and polarimetric instruments.[33]

  • Propulsion module
    Propulsion module

Vikram lander

The Vikram lander was responsible for the soft landing on the Moon. It is also box-shaped, with four landing legs and four landing thrusters capable of producing 800 newtons of thrust each. It carried the rover and has various scientific instruments to perform on-site analysis.[34][35] The lander has four variable-thrust engines with slew rate changing capabilities, unlike Chandrayaan-2's lander, which had five, with the fifth one being centrally mounted and capable only of fixed thrust. One of the main reasons for Chandrayaan-2's landing failure was altitude increase during the camera coasting phase. This was removed by allowing the lander to control altitude and thrust during all phases of descent. Altitude correction rate was increased from Chandrayaan-2's 10°/s to 25°/s with Chandrayaan-3. Additionally, the Chandrayaan-3 lander is equipped with a laser Doppler velocimeter (LDV) to allow measuring altitude in three directions.[36][37] The impact legs were made stronger compared to Chandrayaan-2 and instrumentation redundancy was improved. It targeted a more precise 16 km2 (6.2 sq mi) landing region based on images provided by the Orbiter High-Resolution Camera (OHRC) onboard Chandrayaan-2's orbiter. ISRO improved the structural rigidity, increased polling in instruments, increased data frequency and transmission, and added additional multiple contingency systems to improve lander survivability in the event of failure during descent and landing.[38][37]

  • Lander
    Lander

Rover

The Pragyan rover is a six-wheeled vehicle with a mass of 26 kilograms (57 pounds). It is 917 by 750 by 397 millimetres (36.1 in × 29.5 in × 15.6 in) in size.[39] The rover is expected to take multiple measurements to support research into the composition of the lunar surface, the presence of water ice in the lunar soil, the history of lunar impacts, and the evolution of the Moon's atmosphere.[40][11]

  • Pragyan rover
    Pragyan rover

Payloads

On lander

  • Chandra's Surface Thermophysical Experiment (ChaSTE)
    Chandra's Surface Thermophysical Experiment (ChaSTE)
  • Instrument for Lunar Seismic Activity (ILSA)
    Instrument for Lunar Seismic Activity (ILSA)
  • Langmuir Probe (RAMBHA-LP)
    Langmuir Probe (RAMBHA-LP)

On rover

On the propulsion module

  • Spectro-polarimetry of Habitable Planet Earth (SHAPE) will study spectral and polarimetric measurements of Earth from the lunar orbit in the near-infrared (NIR) wavelength range (1–1.7 μm).[28][29] Findings of SHAPE might aid in future exoplanet research and search for extraterrestrial life.[42]
  • Spectro-polarimetry of Habitable Planet Earth (SHAPE)
    Spectro-polarimetry of Habitable Planet Earth (SHAPE)

Mission profile

   Chandrayaan-3's path ·    Earth ·    Moon