article_snippet.sent: an orbital mission would last approximately 30 months, with nine months of travel each way and 12 months in orbit, the panelists said.
article_snippet.sent: Owing to the orbits of Earth and Mars there are specific windows of opportunity when a mission can take place.
article_snippet.sent: For this reason spacecraft to Mars, such as the Curiosity rover, have to launch in certain windows when Our planets are aligned.
article_snippet.sent: The next window is open from January 2016 to April 2016, and will see the launch of two more missions to the red planet.
article_snippet.sent: For a future manned mission, they will need to launch out in one of the windows and return in one, which will take two years in total.
article_snippet.sent: Just getting there will take up to nine months.
article_snippet.sent: The astronauts will be there waiting for a year until The astronauts can come back - a total of around three years.