GSLV-Mk III / Chandrayaan-2 Mission

Chandrayaan-2, India’s second lunar mission, has three modules namely Orbiter, Lander (Vikram) & Rover (Pragyan). The Orbiter and Lander modules will be interfaced mechanically and stacked together as an integrated module and accommodated inside the GSLV MK-III launch vehicle. The Rover is housed inside the Lander. After launch into earth bound orbit by GSLV MK-III, the integrated module will reach Moon orbit using Orbiter propulsion module. Subsequently, Lander will separate from the Orbiter and soft land at the predetermined site close to lunar South Pole. Further, the Rover will roll out for carrying out scientific experiments on the lunar surface. Instruments are also mounted on Lander and Orbiter for carrying out scientific experiments.

Chandrayaan - 2

All the modules are getting ready for Chandrayaan-2 launch during the  window of July 09, to July 16, 2019, with an expected Moon landing on September 06, 2019.

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 3,877 kg (8,547 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 a 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 mission will carry five instruments on the orbiter. 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. Interfaces between the orbiter and its GSLV Mk III launch vehicle have been finalised. The orbiter's structure was manufactured by Hindustan Aeronautics Limited and delivered to ISRO Satellite Centre on 22 June 2015. 

payload

ISRO selected five scientific instruments for the orbiter, four for the lander, and two for the rover. While it was initially reported that NASAand 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 a last moment update just a month before the launch of the mission, NASA's laser retroreflector was added to lander's payload to help scientists measure exact distances to the moon.

Orbiter payload

1. Large Area Soft X-ray Spectrometer (LASS) from ISRO Satellite Centre (ISAC), Bangalore and Solar X-ray monitor (XSM) from Physical Research Laboratory (PRL), Ahmedabad for mapping major elements present on the lunar surface.
2. L and S band Synthetic Aperture Radar (SAR) 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.
3. Imaging IR Spectrometer (IIRS) from SAC, Ahmedabad for mapping of lunar surface over a wide wavelength range for the study of minerals, water molecules and hydroxyl present.
4. Neutral Mass Spectrometer (ChACE-2) from Space Physics Laboratory (SPL), Thiruvananthapuram to carry out a detailed study of the lunar exosphere.
5. Terrain Mapping Camera-2 (TMC-2) from SAC, Ahmedabad for preparing a three-dimensional map essential for studying the lunar mineralogy and geology.

Vikram lander payload

1. Seismometer for studying Moon quakes near the landing site
2. Thermal probe for estimating the thermal properties of the lunar surface
3. Langmuir probe for measuring the density and variation of lunar surface plasma
4. Radio occultation experiment for measuring the total electron content
5. A laser retroreflector array (LRA) by NASA Goddard Space Flight Center for precise measurements of the Earth–Moon distance.

Pragyan rover payload

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