SpaceX supremo and founder Elon Musk took time out from his Tesla automotive activities to lay out his plans for the Starship via a web interview at the Mars Society’s online conference on 16 October. Musk led with his explanation that for long term long-range human activities on Mars large launch vehicles were need – and ones that were reusable with short turn around times.  While NASA human Mars mission designers will be happy to have a quick launch capability – especially for refueling cryogenic propellants which have a tendency to boil-off fast, any return vehicle they use is more likely to use storable hypergolic propellants  – which while much less efficient in terms of specific impulse – are much more user friendly.

With respect to the propellant combination chosen for the Starship, Musk explained that liquid methane had a much better specific impulse and better better burn ratio with LOx (liquid oxygen) than RP-1 Kerosene.  Musk himself seems set on “in situ” propellant creation via giant machines carried to the Martian surface to produce liquid oxygen made from electrolysing water found on Mars, and creating Methane from the Martian atmosphere.

Elon Musk looks upwards to think as he talks about the Starship timeline at the Mars Society Online conference. Courtesy: The Mars Society via Space.com

While SpaceX has just signed a cryogenic refueling demonstration contract with NASA and is competing its Starship as one of the contenders in the Human Landing System (HLS) competeition, Musk wanted to reiterate that his medium term plans remained targeted Mars and launching a cargo version of Starship there in 2024. “There’s a Mars conjunction every 26 months — this is one of those years — that means 4 years from now is another one. I think we’ve got a fighting chance of making the second Mars transfer window” he said.

Musk was more certain that his Starship design will be flying a long time before that and said he was “80-90 per cent confident” that Starship will reach orbit next year. Whether the machine was able to re-enter and land successfully he was more cautions putting its chance at circa 50 per cent. “We will probably lose a few ships before we get it right,” said Musk.

On the subject of hiring productive and innovative talent for his firms, Musk noted it was difficult to ascertain this directly the interview/recruitment process and that he had found himself musing at his Tesla car company which is named after the electrics genius inventor, “If Nikola Tesla applied for a job at Tesla today, would he be hired?”

Comment by David Todd: Not much detail but interesting and Elon Musk is always watchable.  We still want to know how Starship will return to Earth’s atmosphere – whether from the Moon or Mars? We think that braking to Mach 25 will be needed or Starship will burn up