New Delhi, May 30 : Rocket reusability must be the key feature space companies must develop to help humanity become a spacefaring civilisation, said SpaceX and Tesla CEO Elon Musk on Thursday.

Citing a New York Times article that argued that rival space companies say that Musk's 'SpaceX is using tactics intended to squash them,' Dan Piemont, Founder and President at ABL Spacesystems, an American aerospace and launch service provider, said he disagreed.

Musk replied: 'Thank you for the thoughtful rebuttal.'

He further said: 'I do hope that rocket companies focus on reusability,' noting that SpaceX's rocket 'Falcon is approximately 80 per cent reusable', and 'Starship will eventually take reusability to approximately 100 per cent.'

'That is the fundamental breakthrough needed for humanity to become a spacefaring civilisation.'

Musk noted that 'there are many tough issues to solve' with the 400-foot-tall Starship rocket along with the Heavy booster.

The biggest is 'making a reusable orbital return heat shield, which has never been done before,' said Musk.

The huge Starship vehicle is intended to land astronauts on the Moon during the crewed Artemis 3 mission in 2026.

It has so far had three test flights, and the fourth will take place likely in 'about 2 weeks.'

However, its reusability remains a concern, as the 'shuttle's heat shield required over six months of refurbishment by a large team,' Musk said.

He added that it "will take a few kicks to solve and requires building an entirely new supply chain for low-cost, high-volume, and yet high-reliability heat shield tiles, but it can be done.'

/IANS