CAPE CANAVERAL, Fla. (AP) — Mars is about to be invaded by planet Earth — big time. Three countries — the United States, China and the United Arab Emirates — are sending unmanned spacecraft…
The three nearly simultaneous launches are no coincidence: The timing is dictated by the opening of a one-month window in which Mars and Earth are in ideal alignment on the same side of the sun, which minimizes travel time and fuel use. Such a window opens only once every 26 months.
Mars has long exerted a powerful hold on the imagination but has proved to be the graveyard for numerous missions. Spacecraft have blown up, burned up or crash-landed, with the casualty rate over the decades exceeding 50%. China’s last attempt, in collaboration with Russia in 2011, ended in failure.
Only the U.S. has successfully put a spacecraft on Mars, doing it eight times, beginning with the twin Vikings in 1976. Two NASA landers are now operating there, InSight and Curiosity. Six other spacecraft are exploring the planet from orbit: three U.S., two European and one from India.
The United Arab Emirates and China are looking to join the elite club.
Each spacecraft will travel more than 300 million miles (483 million kilometers) before reaching Mars next February. It takes six to seven months, at the minimum, for a spacecraft to loop out beyond Earth’s orbit and sync up with Mars’ more distant orbit around the sun.