The attraction of becoming the oldest person ever in space is inspiring former Star Trek actor and New Shepard crew member William Shatner to undertake his latest mission.

With Jeff Bezos' Blue Origin set to launch its second human flight tomorrow, Shatner explains why he is delighted to boldly go where no nonagenarian has gone before.

"Because I wanted to claim that I was the oldest person that way. It's one thing to have - these the oldest guy that went into space," he said.

"I want to have the vision. I want to see space. I want to see the Earth. I want to see what we need to do to save Earth. I want to have a perspective that hasn't been shown to me before."

The New Shepard rocket will lift off from Blue Origin’s spaceport in west Texas, carrying four space tourists on a ten-minute ride.

They are Shatner; Blue Origin Vice President of Mission and Flight Operations, Audrey Powers; former NASA engineer, Chris Boshuizen and healthcare entrepreneur Glen De Vries.