Helium Leak in Cryogenic Engine Delayed Chandrayaan-2: Reports
The countdown for the mission commenced on Sunday and scientists were involved in propellant filling.
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The launch of Chandrayaan-2 was called off due to a technical snag on Monday, 15 July. In a tweet, ISRO said that the snag was observed in launch vehicle system, 56 minutes before the launch. The launch was scheduled for 2:51 am.
"It is not possible to make the launch within the launch window. Next launch schedule will be announced later,” the space agency said.
Reports have suggested that a leak in the helium bottle of the cyrogenic engine is what delayed the launch. However, there is no confirmation from ISRO about what exactly was the technical snag.
Scientists have said that the agency will try to get the rocket back by 31 July, before the current launch window ends. The next best window, that ensures full 14 Earth days for the lander and rover on the Moon comes earliest in September next.
- Chandrayaan-2 launch was called off due to a technical snag on Monday, 15 July
- ISRO has not announced the next launch date for the second moon mission
- The Chandrayaan-2 has 13 payloads in total with eight of them in the orbiter, 3 payloads in the lander and two in the rover
- Five payloads are from India, three from Europe, two from the US and one from Bulgaria
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The Challenges Involved
ISRO officials said the challenges involved in the Moon landing were identifying trajectory accurately; taking up deep space communication; trans Lunar injection, orbiting around the moon, taking up soft landing on the moon surface and facing extreme temperatures and vacuum.
Scientists have pegged to make the landing of lander 'Vikram' on September 6 and then undertake a series of complex manoeuvres comprising "rough braking" and "fine braking."
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.
Why Lunar South Pole is the Landing Target
According to ISRO, 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.
Home Grown Technology Deployed in Chandrayaan-2
Through Chandrayaan-2, in which home grown technology is deployed, scientists aim to expand India's footprint in space, shed light on unexplored section of Moon - the South Pole region, enhance knowledge about space, stimulate advancement of technology and promote global alliances.
It is first expedition by ISRO to attempt a soft landing on the lunar surface equipped with “home grown” technology. It would also be the first mission to explore the lunar terrain.
The Trajectory and Landing Plan of Chandrayaan-2
About 16 minutes after the lift-off, the GSLV MkIII will inject Chandrayan-2 into 170 x 40400 kms Earth orbit.
From then onwards, the mission will witness a series of manoeuvres by scientists to carry out different phases of the mission. For the first 17 days from lift-off, the spacecraft will be in Earth-bound phase before its orbit is finally raised to over 1.05 lakh km.
After that, it will be nudged into the Lunar Transfer Trajectory taking it to the proximity of Moon in the next two days. Then gradually over the next few days it will be brought to 100 X 100 km circular orbit when the lander will separate and after another few days of orbiting it will make a soft landing at a chosen place on Lunar surface.
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 degree 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.
The rover can travel up to half a km leveraging solar energy and both Pragyan and Vikram have a mission life of one Lunar day, which approximately equals 14 Earth days.
Chandrayaan-2 Next Leap in Technology: ISRO Chairman
Indicating the challenges involved in soft landing, which will feature a series of critical manoeuvres by scientists, ISRO Chairman K Sivan said they will undergo about "15 minutes of terror (filled moments)."
"Chandrayaan-2 is the next leap in technology as we attempt to soft land close to South Pole of Moon. The soft landing is extremely complex and we will experience approximately 15 minutes of terror," he said ISRO, which has planned for the landing around 6 September, said the mission aims at going where no other nation has so far forayed - the Lunar South Pole and seek 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 NASA is among the payloads and is aimed at understanding dynamics of Earth's Moon system and deriving clues on Lunar interior.
Launch Countdown for Chandrayaan-2 Commences
After a full dress rehearsal last week, the countdown for the mission commenced on Sunday and scientists were involved in propellant filling, ISRO officials said.
"The launch countdown of GSLV-MkIII-M1/Chandrayaan-2 commenced today (Sunday) at 0651 hrs IST," ISRO said in its latest update Sunday.
Chandrayaan-2 is Going to Be ISRO's Most Complex Mission: G Madhavan Nair
On the eve of the Chandrayaan-2 launch, former ISRO Chief, G Madhavan Nair said, that it’s going to be the most complex mission that ISRO has undertaken so far, reports ANI. He said, “Scientifically, it is a follow on mission to confirm data from Chandrayaan-1. It is going to be a big motivator for the young scientific groups.”
Visitors Head to Launch Station
Visitors gather outside Satish Dhawan Space Centre, Sriharikota where Chandrayaan-2 is scheduled to be launched at 2:51 AM on Monday.
Filling of Liquid Hydrogen in Progress
With less than 90 minutes to go for the launch of Chandrayaan-2, the filling of liquid hydrogen in progress, tweeted ISRO.
Filling of liquid oxygen in cryogenic stage of GSLVMkIII-M1 is completed.
Less Than Hour to Go for Launch
In less than an hour, Chandrayaan-2 will be launched. The filling of liquid hydrogen in the GSLV Mk III rocket is now complete, ISRO says.
Countdown Put on Hold
About half an hour ahead of Chandrayaan-2’s launch, the countdown has been put on hold. Further details are awaited from ISRO.
Chandrayaan-2 Launch Called Off Due to Technical Snag
India's second mission to Moon, Chandrayaan-2 has been called off due to a technical snag, ISRO has said.
"It is not possible to make the launch within the launch window. Next launch schedule will be announced later,” news agency PTI quoted ISRO as saying.
K Sivan had Hinted at Tuesday Relaunch Date If Things go Wrong
According to an NDTV report, K Sivan had said that the space agency has another lift-off opportunity on Tuesday, 16 July if it were called off on Monday, 15 July.
However, according to the same report, launch windows have to meet several technical criteria and so it could even take weeks or months for a new date.
Chandrayaan Called Off Due to Leak in Helium Bottle: Reports
A leak in the helium bottle of the cryogenic engine of the GSLV Mk-III, the Chandrayaan-2 launch vehicle is reported by The Times of India to be the 'technical snag' that called off the launch on 15 July at the Satish Dhawan Space Centre in Sriharikota.
The daily said that five sources had independently confirmed to them that the launch was put off because of a leak in the cyrogenic stage.
One source told TOI that the procedure is to pressure the helium bottle up to 350 bars and regulate the output to 50 bars. After filling the bottle, the scientists realised that the pressure was dropping, indicating at a leak. However, the exact spot of the leak was not found by the team.
In fact, a leak of the oxygen tank was detected on 22 June, as well during a ground test of a cryogenic engine.