Entrepreneur Elon Musk is about to outline his vision for establishing a human colony on Mars.
Mr Musk, who founded private spaceflight company SpaceX, is speaking at a conference in Guadalajara, Mexico.

He is expected to talk about the long-term technical solutions needed for the "creation of a permanent base" on the Red Planet.

His company is designing a space launch system that could be used to ferry astronauts between Earth and Mars.

At the weekend, Mr Musk announced that SpaceX had carried out its first test of the Raptor rocket engine, intended to be part of an interplanetary launch system.
His announcement is being watched closely because SpaceX has already made several landmark achievements for a private space company, including the successful upright landings of orbital rocket stages.

SpaceX rocket engineImage copyright SpaceX
Image caption The Raptor engine was fired at SpaceX's test facility in McGregor, Texas
But just journeying to Mars, let alone setting up a permanent base, remains a formidable challenge.

Beyond the astronomical cost, there are the technical hurdles - currently unsolved - of protecting humans from the radiation levels they would be exposed to in deep space.

For Mr Musk, Tuesday's speech should offer welcome respite from dealing with the fall-out of the company's launch pad explosion in September, which destroyed one of the company's Falcon 9 launchers and its payload - an Israeli-built communications satellite for Facebook.

source:bbc.com