Isro locates lander Vikram on Moon, hopes to make contact over next 14 days

Bengaluru: The Indian Space Research Organisation (Isro) has located lander Vikram on the Moon more than 24 hours after losing contact, offering major relief to the space agency.

Isro now faces its biggest challenge of establishing communication with the lander, which scientists say appears unlikely as the spacecraft has apparently made a hard landing on the Moon.

“We have found the location of the Vikram lander on the lunar surface and the orbiter has clicked a thermal image of the lander,” Isro chairman K. Sivan told ANI news agency. He, however, added that scientists are still trying to make contact with the lander. “It (information of any contact with the lander) will be communicated soon,” he said.

A thermal image is made by using radiation from the infrared region of the spectrum, which means that the orbiter has not seen the lander or detected any communication link, but captured the radiations being emitted from it.

Thus, communicating with the lander remains an extremely challenging exercise and the chance of retrieving any data is slim.

However, Isro scientists remain hopeful and said that they would try their best to connect with the lander over the next 14 days, after which the lunar night would begin and the landing site would be covered in darkness.

The lander has apparently made a hard landing on the Moon, Sivan said, and as such parts of it are likely to have been damaged, though Isro has not said this. Thus, even if the space agency locates the lander, it may not be able collect data or perform scientific exercises.

Any major damage would likely render the Pragyaan rover non-functional, making it difficult for the rover to traverse the Moon’s surface.

“It is difficult to ascertain the physical damage of the lander as of now, based on thermal images. However, efforts are on to get as much information as we can,” said an Isro scientist on condition of anonymity.

“Locating the lander would only offer clues on what happened in the last two minutes of the powered descent and where it landed. This information could be useful for planning future Moon missions. However, as far as Chandrayaan-2 is concerned, mission data would now only come from the orbiter,” said a senior scientist.

The orbiter is revolving around the Moon at an altitude of 100km above the surface in a polar orbit and carries seven payloads. It is expected to collect crucial data for the mission.

Communication with the lander Vikram was lost about two minutes before it was scheduled to make a soft landing on the moon around 1.55am on Saturday. Several attempts by scientists at Isro’s mission control complex in Bengaluru to establish a link did not yield results, following which the space agency issued a statement that the data is being analysed to ascertain what happened.

The lander had followed the planned trajectory from its orbit of 35km to 2.1km above the lunar surface during the powered descent. All the systems and sensors of the lander functioned well until 13 minutes of the powered descent early on Saturday, after which the communication link was lost.

Significantly, the orbiter is also continuously revolving, so it comes over the selected landing site for a very short duration.

“The orbiter period is around two hours, but as it is revolving in a polar orbit around the Moon, it will come to the same point only during the next few cycles, after that it will visit that place only after a month and again for 2-3 cycles. So, as time passes by, it will get very difficult to set up communication with the Lander,” said Prof Nirupam Roy, of the Indian Institute of Science, Bengaluru.

This is significant as the lander can communicate with the mission control complex with the help of the orbiter.