Will Chandrayaan-2 Ever Rule the World?

Chandrayaan-2 About this soundpronunciation is India’s second lunar exploration mission after Chandrayaan-1 Developed by the Indian Space Research Organisation (ISRO),the mission was launched from the second launch pad at Satish Dhawan Space Centre on 22 July 2019 at 2.43 PM IST (09:13 UTC) to the Moon by a Geosynchronous Satellite Launch Vehicle Mark III (GSLV Mk III).The planned orbit has a perigee of 169.7 km and an apogee of 45475 Km . It consists of a lunar orbiter, lander and rover, all developed in India.The main scientific objective is to map the location and abundance of lunar water.

The lander and the rover will land in a high plain between two craters, Manzinus C and Simpelius N, at a latitude of about 70° south on 7 th September, 2019. The wheeled rover will move on the lunar surface and will perform on-site chemical analysis for a period of 14days(1 Lunar day). It can relay data to Earth through the Chandrayaan-2 orbiter and lander, which will fly on the same launch.The orbiter will keep working on its mission for 1 year of duration with an circular orbit of 100km.Launch of Chandrayaan-2 was originally scheduled for 14 July 2019 at 21:21 UTC (15 July 2019 2:51 IST) but was called off due to a technical snag noticed around 56 minutes before launch. It was launched on 22 July 2019 14:43 IST (09:13 UTC) from the Satish Dhawan Space Centre at Sriharikota in Nellore district of Andhra Pradesh.

A successful landing would make India the fourth country to achieve a soft landing on the Moon, after the space agencies of the USSR, USA and China.If successful, Chandrayaan-2 will be the southernmost lunar landing, aiming at 67°S or 70°S latitude.

History

On 12 November 2007, representatives of the Russian Federal Space Agency (Roscosmos) and ISRO signed an agreement for the two agencies to work together on the Chandrayaan-2 project.ISRO would have the prime responsibility for the orbiter and rover, while Roscosmos was to provide the lander. The Indian government approved the mission in a meeting of the Union Cabinet, held on 18 September 2008 and chaired by Prime Minister Manmohan Singh.The design of the spacecraft was completed in August 2009, with scientists of both countries conducting a joint review.

Although ISRO finalised the payload for Chandrayaan-2 per schedule,the mission was postponed in January 2013 and rescheduled to 2016 because Russia was unable to develop the lander on time.Roscosmos later withdrew in wake of the failure of the Fobos-Grunt mission to Mars, since the technical aspects connected with the Fobos-Grunt mission were also used in the lunar projects, which needed to be reviewed.When Russia cited its inability to provide the lander even by 2015, India decided to develop the lunar mission independently.

The spacecraft’s launch had been scheduled for March 2018, but was first delayed to April and then to October to conduct further tests on the vehicle.On 19 June 2018, after the program’s fourth Comprehensive Technical Review meeting, a number of changes in configuration and landing sequence were planned for implementation, pushing the launch to the first half of 2019.Two of the lander’s legs got minor damage during one of the tests in February 2019.

Chandrayaan-2 launch was initially scheduled for 14 July 2019, 21:21 UTC (15 July 2019 at 02:51 IST local time), with the landing expected on 6 September 2019.However, the launch was aborted due to a technical glitch and rescheduled to 22 July 2019.

Chandrayaan-2 was launched onboard the GSLV MK III M1 launch vehicle on 22 July 2019 at 09:13 UTC (14:43 IST).

Objectives

The primary objectives of Chandrayaan-2 are to demonstrate the ability to soft-land on the lunar surface and operate a robotic rover on the surface. Scientific goals include studies of lunar topography, mineralogy, elemental abundance, the lunar exosphere, and signatures of hydroxyl and water ice.The orbiter will map the lunar surface and help to prepare 3D maps of it. The onboard radar will also map the surface while studying the water ice in the south polar region and thickness of the lunar regolith on the surface. Chandrayaan-2 will inform the location and abundance of lunar water for exploitation by the future lunar base proposed by the Artemis program.

Design

The mission is planned to fly on a Geosynchronous Satellite Launch Vehicle Mark III (GSLV Mk III) with an approximate lift-off mass of 3,850 kg (8,490 lb) from Satish Dhawan Space Centre on Sriharikota Island.As of June 2019, the mission has an allocated cost of 978 crore (approximately US$141 million) which includes 603 crore for space segment and 375 crore as launch costs on GSLV Mk III.Chandrayaan-2 stack would be initially put in an Earth parking orbit of 170 km perigee and 40,400 km apogee by the launch vehicle.It will then perform orbit-raising operations followed by trans-lunar injection using its own power.

Orbiter

The orbiter will orbit the Moon at an altitude of 100 km (62 mi).The orbiter carries five scientific instruments. Three of them are new, while two others are improved versions of those flown on Chandrayaan-1. The approximate launch mass will be 2,379 kg (5,245 lb).The Orbiter High Resolution Camera (OHRC) will conduct 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 ISRO Satellite Centre on 22 June 2015.

• Dimentions: 3.2 × 5.8 × 2.1 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)
• Mission life: 1 year in lunar orbit
• Power generation capacity: 1000 W

Vikram lander

The mission’s lander is called Vikram About this soundPronunciation named after Vikram Sarabhai (1919–1971), who is widely regarded as the father of the Indian space programme.

The Vikram lander will detach from the orbiter and descend to a lunar orbit of 30 km × 100 km (19 mi × 62 mi) using its 800 N (180 lbf) liquid main engines. It will then perform a comprehensive check of all its on-board systems before attempting a soft landing, deploy the rover, and perform scientific activities for approximately 15 days. The approximate combined mass of the lander and rover is 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 consists of eight 50 N (11 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 liquid engines, but a centrally mounted engine was added to handle new requirements of having to orbit the Moon before landing. The additional engine is expected to mitigate upward draft of lunar dust during the soft landing.Vikram can safely land on slopes up to 12°.

Some associated technologies include a high resolution camera, Lander Hazard Detection Avoidance Camera (LHDAC), Lander Position Detection Camera (LPDC), an 800 N throttleable liquid main engine, attitude thrusters, Ka band radio altimeter (KaRA), Laser Inertial Reference & 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 × 2 × 1.2 m
• 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 W
• Landing site: 70.9 degrees South, 22.9 degrees East (Alternate site:67.7 degrees South, 18.4 degrees West )

Pragyan rover

The mission’s rover is called Pragyan soundPronunciation . The rover’s mass is about 27 kg (60 lb) and will operate on solar power. The rover will move on 6 wheels traversing 500 meters on the lunar surface at the rate of 1 cm per second, performing on-site chemical analysis and sending the data to the lander, which will relay it to the Earth station. For navigation, the rover uses:

• Stereoscopic camera-based 3D vision: two 1 megapixel, monochromatic NAVCAMs in front of the rover will 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.

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 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 this mission. However, in an update just a month before the launch of the mission, a small laser retroreflector from NASA was added to the lander’s payload to help scientists measure exact distances to the Moon and lunar libration.

Orbiter payload

• Chandrayaan-2 Large Area Soft X-ray Spectrometer (CLASS) from ISRO Satellite Centre (ISAC), Bangalore.
• Solar X-ray monitor (XSM) from Physical Research Laboratory (PRL), Ahmedabad for mapping major elements present on the lunar surface.
• Dual Frequency L and S band Synthetic Aperture Radar (DFSAR) from Space Applications Centre (SAC), Ahmedabad for probing the first few tens of metres of the lunar surface for the presence of different constituents, including water ice. SAR is expected to provide further evidence confirming the presence of water ice below the shadowed regions of the Moon.
• Imaging IR Spectrometer (IIRS) from Space Applications Centre (SAC), Ahmedabad for mapping of lunar surface over a wide wavelength range for the study of minerals, water molecules and hydroxyl present.
• Chandrayaan-2 Atmospheric Compositional Explorer 2 (ChACE-2) Quadrupole Mass Analyzer from Space Physics Laboratory (SPL), Thiruvananthapuram to carry out a detailed study of the lunar exosphere.
• Terrain Mapping Camera-2 (TMC-2) from Space Applications Centre (SAC), Ahmedabad for preparing a three-dimensional map essential for studying the lunar mineralogy and geology.
• Radio Anatomy of Moon Bound Hypersensitive Ionosphere and Atmosphere — Dual Frequency Radio Science experiment (RAMBHA-DFRS) by SPL
• Orbiter High Resolution Camera (OHRC) by SAC for scouting a hazard free spot for landing. Imagery from OHRC will later help prepare Digital elevation model of lunar surface.

Vikram lander payload

• Instrument for Lunar Seismic Activity (ILSA) Seismometer by LEOS for studying Moon-quakes near the landing site.
• Chandra’s Surface Thermo-physical Experiment (ChaSTE) Thermal probe for estimating the thermal properties of the lunar surface.
• RAMBHA-LP Langmuir probe for measuring the density and variation of lunar surface plasma.
• A laser retroreflector array (LRA) by NASA Goddard Space Flight Center for precise measurements of the Earth–Moon distance and lunar libration.

Pragyan rover payload

• Laser induced Breakdown Spectroscope (LIBS) from Laboratory for Electro Optic Systems (LEOS), Bangalore.
• Alpha Particle Induced X-ray Spectroscope (APXS) from PRL, Ahmedabad.

Team

The list below lists most key scientists and engineers who were instrumental to the development and launch of Chandrayaan-2 project:

• Muthaya Vanitha — Project Director, Chandrayaan-2
• Ritu Karidhal — Mission Director, Chandrayaan-2
• Chandrakanta Kumar — Deputy Project Director, Chandrayaan-2