Chandrayaan 2: Vikram Lander was half a kilometre away from intended touch down point
Bengaluru, Sep 09: It was the faulty execution of the last stage of the operation due to which the Vikram Lander lost communication. Some scientists, who continue to analyse the data also do not rule out the possibility of an anomaly with regard to the velocity, while landing.
ISRO chairman, D Sivan said that they had found the location of the Vikram Lander on the lunar surface and the orbiter had clicked a thermal image of the lander. However they are still trying to establish contact, the ISRO chief also said.
Sivan said that the last phase was not executed in the right manner and it was in that phase that they lost the link with the lander and could not establish contact.
At 1.45 a.m. on September 7, 12 minutes into its descent onto the lunar surface, the lander lost contact with the earth. It is believed to have deviated from its path, fallen silent, and probably crashed on the moon.
The pictures are among the early images sent later in the day by the main Chandrayaan 2 spacecraft, which continues to orbit the moon from pole to pole from a 100-km distance.
The lander was spotted some distance away - possibly about half a kilometre - from its intended touchdown point, reports said.
The originally chosen region was s about 70° south of the lunar equator and about 600 km from the lunar south pole.
On September 8, news reports quoted ISRO chairman K Sivan as saying the agency was trying to restore contact with the lander.
The image of the lander rover "Pragyan" is housed inside it was captured by the on-board camera of Chandrayaan-2 orbiter, which is healthy, safe and functioning normally in the intended orbit around the moon.
The orbiter camera is the highest resolution camera (0.3m) in any lunar mission so far and shall provide high-resolution images which will be immensely useful to the global scientific community, the Bengaluru-headquartered space agency had said earlier.
Considered as the "most complex" stage of the country's second expedition to the moon, the lander was on a powered decent for a soft landing when it lost contact.
The data is being analysed, the Isro had said soon after.
Asked if the lander was 'damaged" during the 'hard landing", Sivan said: "That we do not know."
But some space experts said Vikram suffering damage in the hard-landing cannot be ruled out.
"It may not have landed at a desired level of velocity. It may not have landed on its four legs. Impact shock may have caused damage to the lander", according to a space official.
"When the system does not work well, it (the lander) will go and hit the moon. There is no ambiguity in that," another veteran space expert said.
"Unless all the things are compensated... Compensating gravity, it (the lander) will not come down smoothly and touch the surface. That's the critical part of the whole manoeuvre," he said.
Sivan had said on Saturday that the space agency would try to establish the link with the lander for 14 days and reiterated on Sunday after it was located on the lunar surface by Chandrayaan-2's onboard cameras that those efforts would continue.
He had said that Vikram lander's descent was as planned and normal performance was observed up to an altitude of 2.1 km, but subsequently, communication from the lander to ground stations was lost.
A senior ISRO official said time was running out and the possibility of re-establishing communication looks "less and less probable".
"Progressively... As time goes by... It's difficult (establish link)," the official said but added that with the "right orientation" it can still generate power and recharge batteries with solar panels.
"But it looks less and less probable, progressively," the official said on condition of anonymity.
According to ISRO, 90 to 95 per cent of the Chandrayaan-2 mission objectives have been accomplished and it will continue to contribute to lunar science, notwithstanding the loss of communication with the lander.
The space agency also said the precise launch and mission management has ensured a long life of almost seven years, instead of the planned one year for the orbiter.
Meanwhile, Sivan said Prime Minister Narendra Modi's address and an outpouring of support and kind words for ISRO after the Chandrayaan-2's Vikram unsuccessful bid to touchdown on Lunar surface have boosted the morale of its scientists and engineers.
"We are extremely happy (the PMs address as well as nation rallying behind ISRO). It has boosted the morale of our people", Sivan said.
"We are so touched, former ISRO chairman K Kasturirangan said.
"The country has given a good, positive response. PM was incredible yesterday," as he praised Modi for inspiring, encouraging and reassuring Sivan and ISRO team and fully backing them.
"The way he (PM) conveyed it... So passionate... So emotional and sometimes rich with meanings and positive responses. I think we could not have expected anything better. Fantastic," he said.
"We are definitely grateful to the nation and PM," said another former ISRO chairman A S Kiran Kumar, who noted that there are hundreds and thousands of variations that were possible for the soft-landing mission, as he underlined the complexities of the mission.
"We appreciate that the country and people were able to actually take note of this and continue to give their support. So, its very positive. We are grateful to the entire country," he said.
Notwithstanding the scientific intricacies of it all, #VikramLanderFound began to trend worldwide on microblogging site Twitter.
Even the government of Israel's official Twitter account said, "Israel followed #VikramLander's ambitious journey to the moon with great hope".
"As we learned from Israel's Beresheet lunar lander, it's never easy, and yet it's a great achievement for #ISRO & Indian science. We're positive that #India will reach the moon (& beyond)!", it tweeted.
In the early hours of Saturday, countless Indians had sat glued to their television sets, praying for a successful landing of Vikram, but it soon turned into a heartbreak despite the module coming tantalising close to the lunar surface.
Another senior ISRO official, however, said time was running out and the possibility of re-establishing communication looks "less and less probable".
But, netizens continued to harbour hope, with much even content with the news of the landing itself.
"#VikramLanderFound ISRO - where are you? Lander Vikram - on the moon ISRO - say something. Lander rover," Sanjeev Gangwar, another user tweeted.
User @onlydimbe shared a clip from the climax scene in the movie Chak De India where the main protagonist gets emotionally overwhelmed, saying, "Every Indian Right now #VikramLander #VikramLanderFound".
Ayon Bhattacharjee, tweeted, "#VikramLanderFound Lander Vikram Located on Moon Surface, trying for communication," and shared two banners, one showing a lunar surface, and the other bearing the word hope in bold letters.
In between, many also posted humour-laden tweets, to acknowledge the landing as reported by ISRO.
But, the feeling of hope and pride in all tweets was unmistakable.
"When I was a kid, I saw people in tears when India lost in cricket. Last night I saw a lot of people in tears because the Vikram lander failed. Doesn't that tell a story of changing India. When kids can spend a sleepless night for a scientific endeavour, India is winning. Jai Hind," wrote @ayonbh.
The successful touch-down would have made India the fourth country after erstwhile USSR, the US and China to achieve a soft landing on the moon, also the first to launch a mission to the unexplored south pole of the Moon.
The orbiter payloads will conduct remote-sensing observations from a 100 km orbit.
Chandrayaan-2, a follow-on mission to the Chandrayaan-1 mission undertaken more than a decade ago, comprises an orbiter, lander (Vikram) and rover (Pragyan).
The orbiter carries eight scientific payloads for mapping the lunar surface and study the exosphere (outer atmosphere) of the moon.
Isro on September 2 successfully carried out the separation of lander Vikram (with rover Pragyan housed inside) from the Chandrayaan-2 orbiter.
The Vikram module, which was supposed to carry out various tests on the lunar soil, had completed the rough braking phase as planned and entered the phase of fine braking at an altitude of 2.1 km when it lost communication.
Isro officials said on Sunday that data available till the lander lost communication with the ground-stations was being analysed to find out what exactly went wrong but declined to specify a timeline for completing the exercise.
"Vikram", named after Vikram A. Sarabhai, the father of the Indian space programme, was designed to execute a soft landing on the lunar surface and to function for one lunar day, which is equivalent to about 14 earth days.
The rover was to roll down from the lander explore the surrounding lunar terrain, a few hours after the planned soft-landing.
Chandrayaan-2 is a 978 crore unmanned moon mission (satellite cost 603 crores, GSLV MK III cost 375 crores).
India's Geosynchronous Satellite Launch Vehicle, GSLV MkIII-M1 successfully launched the 3,840-kg Chandrayaan-2 spacecraft on July 22.