ISRO's upcoming missions - Chandrayaan-4 and 5 - will be important for India's aim to send humans to the Moon and bring them back safely within the next 20 years, Indian Space Research Organisation (ISRO) chairman S Somanath said on August 23.

"The journey of Chandrayaan-3 is going to continue. The model of Chandrayaan-4 is ready. We have proven how to reach Moon. But we have to now prove how to come back from there," S Somanath said at an event in New Delhi to mark the first National Space Day.

"It is important to take the next step because we have an added vision of sending humans to Moon and bring them back safely. So, we have to incrementally progress in the next 20 years to build that capability to land there and come back safely," Somanath added.

The National Space Day commemorates the anniversary of the successful landing of Chandrayaan-3 near the South Pole of the Moon.

On August 23, 2023 India made history after Chandrayaan-3's Vikram lander was the first to land successfully on the South Pole of the Moon. Over the next couple of weeks, the Pragyan rover explored the lunar surface and conducted experiments.

Somanath said that there were were five experiments on Chandrayaan-3 which delivered "excellent data". With the help of insights gained from Chandrayaan-3 project, Somanath said, the agency was able to discover that the lunar surface was once filled with magma.

"Today we have 55 GB of data from Chandrayaan-3," he said. The ISRO chief said that the data has been reviewed and analysed and is going to be made public.

With a larger aim of landing Indians safely on the Moon, the ISRO chief said the agency will work on different technologies required for the same, including developing launch vehicles that are cost effective.

Somanath also said that the government is trying to make India's human space flight mission, Gaganyaan, sustainable, and aims to create a pool of astronauts.

India's proposed space station - Bharatiya Antariksh Station - is being planned as a scientific platform for experiments. "There will a be a huge number of collaboration between academia and industry," he added.

(With Inputs From Agencies)