Richard Branson is about to fly to SPACE – is he safe and how will it happen?

What will happen?

Unlike most spaceflight companies, Virgin Galactic does not use a rocket to reach space.

Instead, its VSS Unity rocket plane ascends toward the heavens strapped to an enormous carrier plane called White Knight Two.

At around 50,000ft above Earth's surface, Unity detaches from its mothership. For comparison, commercial airliners fly at 30,000ft.

Once separated, Unity fires up its rocket engines and flies at a near-vertical angle into suborbital space.

The craft hits around three and a half times the speed of sound (2,600mph or 4,300kph) until it reaches a top altitude of around 293,000ft.

After the rocket motor has fired for around a minute, the pilots safely shut it down, giving riders four minutes of weightlessness.

They can peer at the Earth below through 17 enormous windows that perforate the cabin walls and ceiling.

To descend, the pilots perform a gradual backflip and fire up the engines.

Unity returns to Earth by landing like a commercial airliner on a runway at Virgin Galactic's spaceport in the New Mexico desert.

How safe is it?

Virgin Galactic has flown its rocket planes 23 times, though only four of these have reached the edge of space.

The spaceflights went without a hitch, according to Virgin Galactic. Tragically, the same cannot be said for all of its tests.

In October 2014, a Virgin Galactic ship crashed, killing the co-pilot and leaving the pilot seriously injured.

Witnessws described how the craft exploded in flight above the Mojave Desert in California before debris plummeted to the ground.

It crashed after firing its rocket following a high-altitude drop from the
Virgin Galactic mothership.

Co-pilot t Michael Alsbury was killed in the catastrophe – while the pilot, Peter Siebold, was injured after ejecting. He later recovered in hospital.

An investigation by the National Transportation Safety Board later concluded that Alsbury prematurely unlocked the air brake used for atmospheric reentry, causing the ship to breakup.

Virgin Galactic grounded its spacecraft for two years while it worked on a new design with improved safeguards.

Since then, the company has flown its second craft, VSS Unity, a number of times without serious incident.

When are other billionaires planning space trips?

By joining the flight on July 11, Sir Richard has positioned himself to beat rival billionaire Jeff Bezos into space by nine days.

Bezos, founder of Amazon, will be on board the suborbital flight of the New Shepard spacecraft of his own private rocket company, Blue Origin, on July 20.

Virgin Galactic and Blue Origin, along with Elon Musk's SpaceX, are competing head-to-head in the emerging space tourism business.

Musk has previously said he plans to go to space atop one of his company's rockets but has not given a timeframe for when he expects to fly.

What has Sir Richard said about the flight?

Ahead of the flight on July 11, the British billionaire said his wife may be nervous but he himself wasn't the least bit afraid.

"I've been looking forward to this for 17 years," Sir Richard said in an interview on Tuesday from Spaceport America near the remote town of Truth or Consequences, New Mexico.

He said pre-flight preparations only add to the excitement ahead of Sunday's scheduled launch, which will be taking place one week before his 71st birthday.

"Every bit about it is a pinch-me moment," he said.

Asked how his family reacted to the news that he would join Sunday's crew, Sir Richard said his children - adventurous like him - were excited, but suggested his wife, Joan, while supportive, was more wary.

"My wife is the sort of person who would be terrified on a Virgin Atlantic airplane," he said.

"She's the last person who would want to do something like this. But she's known me since I tried to balloon across the Atlantic or the Pacific or around the world, and she still seems to love us."

He laughed as he quoted his wife telling him: "'If you're foolish enough to do these wonderful things, you can do it, but I won't be going to your funeral.'"

In other news, scientists have identified the place where aliens are most likely lurking in the Milky Way.

Aliens may have dropped life-detecting sensors onto Earth, according to a Harvard University professor.

China has successfully launched three astronauts into orbit to build its own space station.

And, the European Space Agency has revealed it will be sending a probe called EnVision to study the planet Venus.

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