THE first Scot in space is to make history for a second time by taking control of a "milestone" rocket launch in New Mexico this afternoon.

Dave Mackay, from the Scottish Highlands, is one of two pilots on board Virgin Galactic's VSS Unity, which is due to take off at 8am MT - around 3pm GMT.

Sir Richard Branson's company is expected to begin space tourism flights in 2021, with Justin Bieber and Leonardo DiCaprio among the first 600 paying customers who have signed up so far.

Today's flight will be the first of three final demonstration flights before the tourism service begins next year.

Former Nasa astronaut CJ Sturckow will join chief test pilot Dave Mackay on the flight. 

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They will both be wearing special suits which were specifically designed to support flying regularly at over three times the speed of sound into space and back.

Mackay said: “It’s a real honor for all of us in the Virgin Galactic Pilot Corps to wear these spacesuits.

"The thoughtfulness of the design ensures the suits are not only comfortable and practical, but also bespoke to each pilot. As soon as you step into the suit, you immediately get a sense of the significance of our mission.

"I’m very much looking forward to wearing my own spacesuit during New Mexico’s first human spaceflight and then many times in the future as we share the wonder of space with our Future Astronauts.”

The National: Credit: Virgin Galactic, TwitterCredit: Virgin Galactic, Twitter

The flight is expected to fulfill a number of objectives, including testing elements of the customer cabin as well as assessing the upgraded horizontal stabilizers and flight controls during boost.

The flight will also carry payloads as part of the NASA Flight Opportunities Program.

Mackay made history last year when he was at the helm of Virgin Galactic's latest test flight of its commercial space fleet, SpaceShipTwo.

The 62-year-old became the first ever Scot to enter space, despite reports that astronaut Brian Binnie took the title back in 2004.

Although his father is Scottish and he himself grew up in Aberdeenshire, Brian was born in West Lafayette, Indiana, in the United States.

Michael Colglazier, CEO, Virgin Galactic said: “With safety as our core priority, we remain committed to completing our first powered flight in New Mexico. In accordance with local government guidelines and safety protocols, we have minimized the number of people onsite to the greatest degree possible.

"While on this occasion no media or guests will be allowed onsite, our team will endeavour to capture and share the beautiful images with the world after the flight has been completed. We look forward to completing this important milestone in our test flight program in the coming weeks.”

Gov. Michelle Lujan Grisham said: “I’m grateful to Virgin Galactic, as I am to every business in our state, for their commitment to safety in this difficult time.

"This is an exciting announcement that demonstrates we have gotten back on track in a safe and speedy manner. New Mexico’s future on the cutting edge of aerospace development is brighter than ever.”