The health of astronauts will be one of the main challenges for Musk.
Musk's know-how cannot be dismissed but there are significant challenges standing between him and his dream of colonising Mars.
Hospitable? Valles Marineris on Mars.
Kevin Gill from Nashua, NH, United States
A true plan for the colonisation of Mars should include both the social and technical feasibility of living there. Unfortunately, Musk left that bit out.
The HI-SEAS mission gives people a chance to practise on Earth what life would be like on Mars. A crew member here from the 2015 mission.
Flickr/University of Hawaii/HI-SEAS
What's the best way to find out how people will cope with the journey to Mars and life on another planet? Lock a test crew up for a year in a simulation right here on Earth.
What could be out there? That question eventually led to the discovery of Pluto.
The existence of a "Planet X" in the outer solar system was the subject of great speculation, and was finally settled with the discovery of Pluto in 1930.
Pluto’s newly clear topography.
NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
Photos from the spacecraft's close approach are dazzling. They and other data from the mission will fill in some of the blanks about Pluto and provide a snapshot of the infant solar system.
Pluto’s enigmatic companion Charon.
What can the data from New Horizons tell us about the dwarf planet's five moons?
High resolution view of a 300 km wide region of Pluto. But where are the impact craters?
Lack of impact craters intrigues space experts who say it suggests the dwarf planet may be geologically active.
Artist’s impression Pluto and it’s largest satellite Charon. Is this how the dwarf planet will look as New Horizons swings past?
Pluto is one of the most enigmatic objects in our solar system, and its secrets are soon to be uncovered by the New Horizons probe.
What mysteries lie beneath your icy crust, Europa?
NASA has now formally started to pack its bags for the next big discovery mission, this time heading to Jupiter’s icy moon Europa. Last month NASA announced the instruments that will fly on this trip and…