Article Posted on : - Jul 22, 2019

ISRO's most powerful rocket GSLV MkIII-M1 carrying the Chandrayaan-2 spacecraft lifts off from the Satish Dhawan Space Centre, at Sriharikota in Andhra Pradesh, on Monday, July 22, 2019. Image: ISRO

SRIHARIKOTA, ANDHRA PRADESH (PTI): Aiming to take a "billion dreams to the moon", India on Monday successfully launched its second lunar mission Chandrayaan-2 on-board its powerful rocket GSLV-MkIII-M1 from the Sriharikota spaceport to explore the uncharted South Pole of the celestial body by landing a rover.

The geosynchronous satellite launch vehicle lifted-off from the Satish Dhawan Space Centre into cloudy skies at 2.43 pm (1443 IST) and successfully placed the 3,850-kg Chandrayaan-2 into the earth orbit 16 minutes and 14 seconds later.

Immediately after Chandrayaan-2's separation from the rocket, the solar array of the spacecraft automatically got deployed and the ISRO Telemetry, Tracking and Command Network at Bengaluru successfully took control of the spacecraft, the Indian Space Research Organisation (ISRO) said in a statement later.

According to the statement, Chandrayaan-2, a three-module spacecraft comprising orbiter, lander and rover, will be subjected to a series of orbit manoeuvres using its onboard propulsion system to take it to the vicinity of Moon over the next weeks with the rover soft landing planned on September 7.

The success of the mission, helmed by two women Ritu Karidhal (Mission Director) and M Vanitha (Project Director), brought huge relief for ISRO scientists after the July 15 launch was called off just about an hour left following a technical glitch in the rocket.

The Rs 978 crore mission, that will mark a giant leap in India's space programme and make it only the fourth country to land a rover on Moon, was rescheduled to Monday after scientists corrected the technical glitch in the three-stage rocket.

In a textbook launch, the towering GSLV-MkIII-M1, in its first operational flight, lifted off majestically from the second launch pad at the Satish Dhawan Space Centre, over 100 km from Chennai, as the scientists broke into jubilation.

"Chandrayaan-2 is unique because it will explore and perform studies on the South Pole region of lunar terrain which is not explored and sampled by any past mission. This mission will offer new knowledge about the Moon," Prime Minister Narendra Modi said in a congratulatory tweet.

Defence Minister Nirmala Sitharaman, Chief Ministers of Kerala and Tamil Nadu K Vijayan and K Palaniswami respectively and Kerala Governor P Sathasivam were among those who congratulated ISRO for the feat.

Scientists led by ISRO chief K Sivan watched the launch sequence in rapt attention and broke into applause after every key stage of the rocket’s flight which progressed precisely as programmed.

A visibly relieved Sivan, who announced the success of the mission, said, "It is the beginning of a historical journey of India towards the moon".

"Today is a historical day for Space Science and Technology in India. I am extremely happy to announce that GSLV MkIII-M1 successfully injected Chandrayaan-2 into an orbit of 6,000 Km more than the intended orbit...," he said.

"We bounced back in flying colours after the earlier technical snag," he said about the glitch that made the space agency reschedule the Chandrayaan-2 launch from July 15 to Monday.

There will be 15 "very crucial manoeuvres" in the next one and half months before the orbiter is brought around the Moon, he said in his post-launch address from mission control centre.

"After that the D-Day will come and on that day we are going to experience 15 minutes of terror, to ensure the landing is safely near the South Pole," he added.

ISRO had last week called off the launch with just 56 minutes of the countdown left, a decision that was later hailed by space experts as a prudent measure not to risk the mission.

After taking remedial action based on an analysis carried out by a team set up to look into the snag, the space agency announced the rescheduled lift-off four days ago, indicating the confidence of the scientists which stood vindicated with the successful launch.

"Chandrayaan 2 is ready to take a billion dreams to the Moon now stronger than ever before! Join us for the launch on Monday 22 July, 2019 at 2:43 PM IST," ISRO had tweeted on July 18 while announcing the rescheduled launch.

Chandrayaan-2 comes 11 years after ISRO's successful first lunar mission Chandrayaan-1 which scripted history by making more than 3,400 orbits around the Moon and was operational for 312 days till August 29, 2009.

Billed as the most complex and prestigious mission undertaken by ISRO since its inception, Chandrayaan-2 will make India the fourth country to soft land a rover on the lunar surface after Russia, the United States and China.

The 43.43m tall rocket GSLV-MkIII-M1, dubbed as Baahubali for its ability to carry heavy payloads, successfully placed the Chandrayaan-2 into an elliptical earth orbit.

The spacecraft is now revolving round the earth with a perigee (nearest point to Earth) of 169.7 km and an apogee (farthest point to Earth) of 45,475 km, ISRO said.

From here onwards, the mission will undergo a series of manoeuvres to carry out different phases of the mission over the next 48 days before the soft landing in the South Pole region of the Moon where no country has gone so far.

Subsequent to the rescheduling of the launch, the space agency has tweaked the orbital phases, increasing Earth-bound phase to 23 days as against 17 days planned originally.

Using the onboard propulsion system, scientists will undertake a series of manoeuvres to raise the Chandrayaan-2 orbit in steps and then place it in the Lunar Transfer Trajectory to enable the spacecraft travel to the vicinity of the Moon, the ISRO statement said.

After leaving earth orbit and on entering Moon's sphere of influence, the propulsion system of Chandrayaan-2 will be fired to slow down the spacecraft to capture a preliminary orbit around the Moon.

It would then perform a series of complex braking manoeuvers and the soft landing of the lander – Vikram carrying rover Pragyan, one of the toughest phases of the mission and described by the ISRO chief as "15 minutes of terror (filled moments), would be made.

The mission, which carries a total of 13 payloads, including three from the Europe, two from the US and one Bulgaria, seeks to improve understanding of the Moon which could lead to discoveries that will benefit India and humanity as a whole.

A Laser Retroreflector Array (LRA) of US space agency NASA is among the payloads and is aimed at understanding dynamics of Earth’s moon system and deriving clues on Lunar interior.

According to ISRO, the mission objective was to develop and demonstrate the key technologies for end-to-end lunar mission capability, including soft-landing and roving on the lunar surface.

It aims to further expand knowledge about the Moon through a detailed study of its topography, mineralogy, surface chemical composition, thermo-physical characteristics and atmosphere leading to a better understanding of the origin and evolution of the Moon.

ISRO said the lunar South Pole is an interesting surface area which remains in shadow than North Pole.

There is a possibility of the presence of water in permanently shadowed areas around it, the agency said, adding craters in the South Pole region have cold traps and contain fossil record of the early Solar System.

The lander Vikram, named after father of Indian space research programme Dr Vikram A Sarabhai, carrying the rover Pragyan, will be landed in a high plain between two craters at a latitude of about 70 degrees South of the moon.

Then the 27-kg Pragyan meaning wisdom in Sanskrit and a six-wheeled robotic vehicle, will set out on its job of collecting information on lunar surface.

A safe site free of hazards for landing would be decided based on pictures sent back by the camera onboard the lander and after touchdown the rover will carry out experiments for 14 Earth days, equals one Lunar Day.

The launch was witnessed by 7,500 people who were accommodated at a viewing gallery, located a few kms from the launchpad, thrown open to the public by the ISRO in May last.