Chandrayaan II - the details and what to look out for !!

The trajectory of the rocket and the spacecreft

In spite of all the high profile Apollo missions by US planned under a spirited Kennedy administration in the early 60s and executed by the Nixon administration in the late sixties, 1969 to be precise, it took 39 more years until Indian ISRO’s lunar orbiter Chandrayaan I discovered the presence of magmatic water on a moon crater in 2008.
  

Even though US disbanded the successful Apollo Moon Mission programme by Dec. '72 after 7 missions after the Apollo 17 mission, the data brought down from lunar atmosphere and rock samples from lunar surface were not tested for water presence, considered the most vital element in the subsistence of organic life as we know it, anywhere in the Universe. Even though controversies abound, if the US moon landings are ever debunked by future generations, it will indeed be a sad day for global science and technology ..

Click here for the Astronomy Now website that gives a very clear pic of the mission ..

The assembly of the spacecraft payloads traveling to lunar orbit

The second Indian mission Chandrayaan II is headed for a landing of the lander Vikram for the first time ever in the treacherous area exactly 600 kms away from the South Pole of the moon between the craters Manzenius C and Simpelius N at 70 degree South latitude on 6 September 2019. The rover Pragyaan in the lander has a one lunar day life (14 earth days) and is capable of moving 150-200 m on lunar surface.

There are a lot of ifs here, but on a positive note, will it make some surprising discoveries about the origin of the moon ?

Forever indebted to Nehru ..

What is the difference between the Chandrayaan I and Chandrayaan II missions ?

1. Chandrayaan I spacecraft was just an orbiter of the moon with a crash landing module (finished it's mission in 2008 itself) while Chandrayaan II is planning a soft landing on the moon using a lander and move a robotic rover on lunar surface for about 200 m to collect data for studying it's origins.

2. Chandrayaan I was launched on a less powerful rocket, Polar Satellite Launch Vehicle (PSLV C11) which through a series of slingshot missions helped the spacecraft of the Chandrayaan I orbiter escape the earth's gravitational pull. In contrast, Chandrayaan II uses the Geostationary Launch Vehicle (GSLV Mk III) with higher power that vertically takes off and develops enough thrust to escape the earth's gravitational pull. The spacecraft is put on the solar orbit after six slingshot maneouvres for its seven week sojourn to the lunar orbit.

3. Chandrayaan I mission objectives were to just orbit the moon and crash land a module while Chandrayaan II objectives are much laudable and can help throw light on the evolution of the solar system itself.

Why are we interested in knowing about the origin of the moon ?
Firstly, it will help us to understand the formation of the other planets and their moons a couple of billions of years back and secondly, perhaps throw light on the formation of the solar system and galaxies billions of years back.  It is going to be a scientific and technological treat for the scientific and technical brains of the space agency as well as a treat for the people of the world to know how their planet came to be what it is today after 4.6 billion years of evolution. A great satisfaction for the Engineers and Scientists at ISRO to have furthered the frontiers of knowledge in understanding the Solar system ..

There are presently 4 theories floating in scientific circles about the origin of the moon. 

Sept 6, 2019 will be a great day for Indian space research .

1. Double Planet Theory (Co-creation theory) - at the origin of Universe itself, Earth and moon were co-created as separate planets

2. Fission Theory - material spun off from earth over millions of years resulting in the formation of the moon

3. Capture Theory - Space debris floating around was captured by Earth and one of the captured large debris happened to the moon

4. Large Impact Theory (Giant Impact Hypothesis)  - an unknown large object is said to have impacted the earth resulting in many fragments. The heavier fragments coalesced to form the Earth and the lighter fragments got thrown off and became the moon.

Even though the Moon is the closest space object from the earth, we still do not known how it was formed and when. Probably Chandraayan 2 would throw more light on the origin of the moon and help us to debunk the other three ..

The mission in brief ..

The safe ejection from the Chandrayaan II orbiter, of the Lander (Vikram) and Rover (Pragyaan) from a 100 km altitude orbit, riding piggyback on 3.3 T space vehicle is very crucial. The craft is taken outside earth orbit on the 640 T GSLV MkIII M1 rocket from Sriharikotta. The trip in the sun's orbit over a 6 week long period covering 3,82,000 kms is an event the whole world is eagerly looking forward to. 

India's successful Chandraayan I launched in 2008 had the orbiter and the Moon Impact Probe while this mission comes with the complete package to walk around the moon and do some basic and simple data collection and experimentation.

Even though the Chandraayan II project should have taken place around 2012-13 as per original plans, due to unforeseen delays with a collaboration with Russia for the lander and the rover technology, that did not materialise, it got delayed. Then India, thanks to the government at that time which gave full support, embarked on the indigenous technology route when the lander and rover were developed indigenously all alone. The project thus got extended to 2019.

The list of instruments on the Orbiter, lander and rover are given below. (courtesy space.com, click here for the link)

On the Orbiter :

• Terrain Mapping Camera 2 (TMC-2), which will map the lunar surface in three dimensions using two on-board cameras. A predecessor instrument called TMC flew on Chandrayaan-1.
• Collimated Large Array Soft X-ray Spectrometer (CLASS), which will map the abundance of minerals on the surface. A predecessor instrument called CIXS (sometimes written as C1XS) flew on Chandrayaan-1.
• Solar X-ray Monitor (XSM), which looks at emissions of solar X-rays.
• Chandra's Atmospheric Composition Explorer (ChACE-2), which is a neutral mass spectrometer. A predecessor instrument called CHACE flew on Chandrayaan-1's Moon Impact Probe.
• Synthetic Aperture Radar (SAR), which will map the surface in radio waves. Some of its design is based on Chandrayaan-1's MiniSAR.
• Imaging Infra-Red Spectrometer (IIRS), which will measure the abundance of water/hydroxl on the surface.



Pragyaan in close quarters ..

• Orbiter High Resolution Camera (OHRC) to examine the surface, particularly the landing site of the lander and rover.
• Laser Retroreflector Array (LRA) from NASA

The lander's instruments include:

• Instrument for Lunar Seismic Activity (ILSA), to look for moonquakes.
• Chandra's Surface Thermophysical Experiment (ChaSTE), to examine the surface's thermal properties.
• Radio Anatomy of Moon Bound Hypersensitive ionosphere and Atmosphere (RAMBHA-Langmuir Probe), to look at plasma density on the surface.

The rover instruments include : two science instruments to look at the composition of the surface:

• the Laser-Induced Breakdown Spectroscope (LIBS) and 
• the Alpha Particle X-Ray Spectrometer (APXS).      courtesy space.com

The mission in graphics, courtesy ToI ..

What happens on lunar surface ??  

The orbiter at a height of 100 km above lunar surface with release the lander-rover combo for a soft landing on lunar surface. After detaching itself from the lander, the rover Pragyaan will spend a lunar day, almost 14 earth days on the lunar surface and walk about 150 - 200 m on the unexplored rocky terrain in the South pole of Moon from Sept 6 to Sept 20, 2019 collecting data and samples of surface rocks.

It is the first time that any country is attempting a landing on the dark side of the moon in the Southern hemisphere.

George ..