The trip takes around seven months; a bit longer than astronauts currently stay on the International Space Station.
The precise duration of each journey depends on when it is taken. Because both Mars and Earth's orbits are not perfectly circular, the time it takes to travel between them varies from six to eight months.
The exact dates and years in which Mars One plans to execute the various stages of the plan were chosen for the beneficial astronomical position of Earth and Mars. When determining the course to Mars, the maximum travel time for the astronauts is very important.
The most efficient route to take from Earth’s orbit to that of Mars is called the ‘Hohmann Transfer Orbit’ (see: illustration). The illustration shows a simplification of the process, as both Earth and Mars’ orbits are not perfect circles.