Star Trek's William Shatner to nervously go where no 90-year-old has gone before

It's one small step for man, one giant leap for ageing television sci-fi stars.

On Wednesday, William Shatner, the 90-year-old actor who starred as Captain Kirk in Star Trek, is due to blast off to the final frontier.

Shatner will become the first nonagenarian to achieve the feat as he sits upfront a New Shepard rocket launched by Jeff Bezos's Blue Origin space tourism company.

Ahead of the mission Shatner, famed for his Star Trek catchphrase "Beam me up, Scotty," admitted: "I'm terrified. "I know! I'm Captain bloody Kirk and I'm terrified!"

The actor added: "I'm thrilled and anxious, and a little nervous and a little frightened, about this whole new adventure. I plan to be looking out the window with my nose pressed against [the] window.

"I'm going to see the vastness of space and the extraordinary miracle of our Earth and how fragile it is compared to the forces at work in the universe."

Shatner said he expected the experience to be "life changing" and to reinforce his belief that humans should treat the planet better.

He said: "We’re vomiting and puking on [the Earth]...we’ve got to stop folks, we’ve really got to stop."

As Captain James T Kirk in Star Trek, Shatner commanded the starship USS Enterprise on its mission to "boldly go where no man has gone before".

The show was first broadcast in 1966 and inspired generations of devoted fans known as "Trekkies".

Shatner's real-life space mission was delayed for a day due to bad weather.

He is due to blast off from the Texas desert at 9am local time (3pm UK time) on Wednesday and the flight will be streamed online:

The trip will last about 10 minutes but he will cross the Karman line at 100km (62 miles) up, which is widely regarded as the start of space, and he will experience weightlessness.

It is Blue Origin's second crewed mission after Mr Bezos was on board the first one in July.

The flight is fully automated so Shatner will at no point need to take command of the ship.

His fellow passengers will be a Blue Origin executive and two paying customers.

Shatner, a compulsive tweeter, said he hadn't been allowed to bring his phone to space, so he wouldn't be able to post.

But ahead of the mission he tweeted a photograph of himself and his fellow soon-to-be astronauts in their blue flight suits.

They did not look much different from the yellow outfit he wore playing Captain Kirk in the 1960s.

"Aren't we all adorbs!" Shatner wrote.

Bezos has long been a fan of Star Trek and offered an invitation to Shatner to fly to space as his guest.

The rocket is taking off from near Van Horn, a small ranch town of 1,800 people in western Texas.

Becky Brewster, mayor of Van Horn and a lifelong "Trekkie," said: "It's time Captain Kirk actually physically got up into space. I'm kind of excited about that.

"He and Mr Spock were the ones that got me interested in space and science fiction and everything else."

The launch is happening two weeks after the US Federal Aviation Administration said it will review safety concerns raised by former and current Blue Origin employees who claimed the company was prioritising speed and cost savings.

Blue Origin has called its New Shepard rocket "the safest space vehicle ever designed or built".