Long-lost footage of Neil Armstrong descending the ladder of the Apollo 11 lunar module will be screened in public for the first time in Sydney next week, according to a prominent astronomer.

The footage runs for a few minutes and is considered to be some of the best footage of the historic 1969 moonwalk, but the film was lost in archives for many years and was badly damaged when found, said John Sarkissian.

It depicts the first few minutes of Armstrong’s descent which was recorded in Australia as Nasa was still scrambling for a signal, showing a far clearer image than was initially screened worldwide.

Telescopes in remote Australia played a key role in the Apollo 11 mission, including provision of the television signal, after Mr Armstrong decided to attempt the moonwalk early, putting the US just beyond the horizon.

Mr Sarkissian – historian and astronomer in charge of the Australian side of the recordings restoration project – said the unseen minutes were the “best quality of Armstrong descending the ladder.”

“Nasa were using the Goldstone (California) station signal, which had its settings wrong, but in the signals being received by the Australian stations you can actually see Mr Armstrong.”

“In what people have seen before you can barely see Mr Armstrong at all, you can see something black – that was his leg.”

The segment which runs for “just a few minutes” will be screened at the awards night of Australian Geographic magazine on Wednesday, at which Apollo 11 astronaut Buzz Aldrin will be the chief guest.