Set to be launched on July 15 from Satish Dhawan Space Centre, this mission will be the world’s first to explore the South Polar Region of the Moon. Chandrayaan 1 was launched successfully on October 22, 2008, and the second mission is seen as a logical extension of the previous mission. The mission will be aboard GSLV-Mk III launch vehicle and will consist of various payloads each performing a specific task.
The mission is tasked to conduct topographical studies as well as analysis of the minerals present on the surface. This mission will also analyse and extend the observations of Chandrayaan 1 namely the discovery of water molecules.
The aim of the mission as set by ISRO are as follows.
- To further extend the space footprint of India.
- To instil inspiration in future generations of Indian scientists, engineers, and explorers.
- Surpassing international aspirations.
Update (July 15): The launch of Chandrayaan 2 has been postponed. “A technical snag was observed in launch vehicle system at one hour before the launch. As a measure of abundant precaution Chandrayaan-2 launch has been called off for today. The revised launch date will be announced later,” ISRO’s statement reads.
Update 1 (July16): Chandrayaan 2 will now launch on July 22, 2019.
Update 2 (July 22): Chandrayaan 2 has successfully takes off at 2:43pm (IST)
Why the moon was chosen?
Moon is the closest natural satellite to the earth and can be a potential test base for deep space explorations. After a considerable dormant period, there is a renewed interest in lunar exploration. Recently, Chang’e 4 mission of China achieved a soft landing on the far side of the moon, the first of its kind. NASA is also planning the Lunar Flashlight mission for the year 2020.
Lunar South Pole
Chandrayaan 2 plans to soft-land on the Southern Polar Region of the moon, September 6, 2019. A soft landing is a controlled landing resulting in zero damage to the lander. The Southern Region, much like the far side, is not yet explored. The South Pole of the moon is much larger than the lunar North Pole. The Southern region remains in shadow and hence is relatively undisturbed and thus has a high probability of having the presence of water molecules. Also, the south pole has cold trap craters.
A cold trap is an area of very low-temperature and the ice trapped in those regions is geologically very old. A cold trap region can also contain water and other volatiles, which would otherwise have been evaporated. There is a possibility that cold trap craters might contain fossil records
GSLV-Mk III Launcher: Functionality
GSLV-Mk III is a powerful three-stage carrier rocket consisting of two solid strap-ons and a core liquid booster as well as a cryogenic upper stage. GSLV-Mk III is designed to carry 4,000 kg payload to the Geosynchronous Transfer Orbit (GTO), which at an altitude of about 36000 km, and about 8,000 kg payload to Low Earth Orbits, which at the altitude of 600 km.
The two strap-ons or the solid rocket boosters — labelled as S200 — carry 205 tons of composite solid propellant each of which is ignited to provide lift-off to the vehicle. The function time is 140 seconds. After 114 seconds into the lift-off, the indigenous Vikas liquid engines will ignite, further assisting the lift-off. The solid rocket boosters were developed at Vikram Sarabhai Space Centre.
Chandrayaan 2 Payloads
The mission payloads will include an Orbiter, a Lander and a Rover. Let us see the payloads individually.
With a mission life of one year, the orbiter will serve as a communication link between the lander and the Indian Deep Space Network (IDSN). IDSN is a communication facility of ISRO and is located in Byalalu village, near Bangalore. This is the same type of orbiter used in Chandrayaan 1 mission earlier.
The orbiter weighs 2,379 kg and will be placed in a 100×100 km lunar polar orbit. The power generation capacity of the orbiter will be 1,000W.
The payloads of the orbiter include:
- Terrain Mapping Camera for mapping the lunar surface.
- Chandrayaan 2 Large Area Soft X-ray Spectrometer (CLASS) for detecting the presence of major elements by measuring their characteristic X-ray, which will be emitted when the Sun’s rays strike the elements.
- Solar X-ray Monitor (XSM) for measuring the intensity of Solar Radiations.
- Orbiter High-Resolution Camera (OHRC) for providing high-resolution images of the surface ensuring a safe landing.
- Imaging IR Spectrometer (IIRS) will perform the Mineralogical and Volatile Mapping of Lunar Surface. Alongwith the complete identification of water/hydroxyl geography. IIRS will also measure the reflected solar radiation from the Moon’s surface
- Dual Frequency Synthetic Aperture Radar (SAR) is used for high-resolution polar lunar mapping, quantitive estimation of ice, and regolith thickness estimation as well as distribution.
- Chandrayaan 2 Atmospheric Compositional Explorer 2 (CHACE 2) for the in-situ study of the properties of the lunar exosphere.
- Dual Frequency Radio Science (DFRS) Experiment for analysing the evolution of electron density in Moon’s atmosphere
The lander, Vikram, is designed to operate for a lunar day (14 earth days). The weight is 1471 kg and the power generation capacity is 650W. The lander is designed for soft-landing and will communicate with IDSN and Orbiter as well as with the Rover. The expected landing is on September 6, 2019.
The payload of the lander will include
- Radio Anatomy of Moon Bound Hypersensitive ionosphere and Atmosphere (RAMBHA) for measuring the electron density and temperature at the lunar surface and to measure the evolution of lunar plasma density under variations in solar conditions.
- Chandra’s Surface Thermo-physical Experiment (ChaSTE) for measuring the vertical temperature gradient as well as the thermal conductivity of the surface.
- Instrument for Lunar Seismic Activity for measuring the various properties of lunar earthquakes like ground displacement, velocity, and acceleration.
Named Pragyan, it is a six-wheeled robotic vehicle with a travelling capacity up to 500m. It can communicate only with the lander. The payloads of the rover include the following.
- Alpha Particle X-ray Spectrometer (APXS) for determining the rock composition near the landing site and will use Curium (244) for X-ray fluorescence spectroscopy.
- Laser Induced Breakdown Spectroscope (LIBS) for identifying the elements near the landing site.
A passive experiment will also be conducted by the Laser Retroreflector Array (LRA) for understanding the moon’s interior.
If Chandrayaan 2 meets success, it will be a boon for future space projects undertaken by ISRO and will establish a strong footing for the organisation in space exploration — building upon the success of Mangalyaan, India’s Mars Orbiter Mission launched in 2013.
ISRO is undertaking several other space projects and we have covered the key ones, which you should check out here.