Chandrayaan-2 will take Nasa-Isro ties to a new height

The first glimpse of the lander and the orbiter. Image credit Tech2

The first glimpse of the lander and the orbiter. Image credit Tech2

Chandrayaan-2 consists of an orbiter, a lander (Vikram), and a rover (Pragyan).

India's second mission to the moon, Chandrayaan-II, will be launched on July 15 at 2.51 am, ISRO chairman K Sivan said here on Wednesday. It will take close to close to 50 days for the spacecraft to land on the moon on September 6 or 7.

Unveiling the spacecraft, ISRO chairman K. Sivan said Chandrayaan-2 will be launched on 15 July at 2.15 am from the spaceport of Sriharikota, Andhra Pradesh.

After a journey of more than 50 days, ISRO's lander will attempt a "soft", controlled landing on the lunar surface on around September 6. Two Chandrayaan modules - an orbiter and a lander - will be stacked together inside a launch vehicle equipped to lift heavy satellites into orbit.

"At an appropriate time, the lander will separate from the orbiter and lander will be set in action, using propulsion system to reduce its orbit and will stay for 4 days", Dr Sivan said.

Rover would roll out for carrying out scientific experiments on the lunar surface, it said, noting that instruments were also mounted on Lander and Orbiter for carrying out scientific experiments.

If successful, India will be only the fourth country to make a soft landing on the moon - in which vehicles touch down without damage - after the former Soviet Union, the US and China. They were revealed at the ISRO Satellite Integration and Testing Establishment facility in Bengaluru. Sivan describes these 15 minutes as the "most terrifying moment".

The upcoming moon mission is the most complex ISRO has attempted.

Chandrayaan-2 will carry 13 scientific satellites with it and weighs about 3.8 tonnes, the equivalent of eight elephants, Sivan said. These payloads are expected to analyse the water on the lunar surface, monitor lunar quakes, dig and study minerals and more. After the launch, it will take 16 days to raise the orbit and then five days to reach the moon's orbit.

The Chandrayaan-2 was originally planned as a collaboration with Russia's Roscosmos space agency, but in 2013 India scrapped the tie-up due to technical differences with the Russian programme. The rover is expected to send data through the lander.

ISRO has scheduled several more missions including the first manned mission to space in 2021, Aditya-L1 or the solar mission in 2021, Mars Orbiter Mission-2 in 2022 and Venus mission in 2023 among others.

Soft-landing on the south pole of the moon, a territory that has never been visited by any spacecraft, is considered the most challenging part of the mission.

Upon launch, the GSLV rocket will travel east for 15 minutes and release the spacecraft into an eccentric orbit of 178 x 38,000 km. That isotope is limited on Earth yet so abundant on the moon that it theoretically could meet global energy demands for 250 years if harnessed.

Chandrayaan 2 is an advanced version of the previous Chandrayaan 1 mission successfully launched about 10 years ago.