Mission to Mars

On April 7, 2001, the Mars Odyssey Orbiter took off from Cape Canaveral, FL, onboard a Boeing Delta 7925 rocket. It traveled for approximately six months before positioning itself into an initial elliptical capture orbit. After a propulsive maneuver into a 25-hour capture orbit, aerocapture was used over the course of 76 days to achieve the two-hour science orbit. Aerocapture involves using the Mars atmosphere to slow down and attain orbit.


Photo courtesy NASA
The Mars Odyssey Orbiter was scheduled to circle Mars for
two years looking for water and analyzing the elements
of the planet.

Aerocapture replaces the conventional thrusters that were once needed for a spacecraft to change course and go into orbit around a planet. Without aerocapture, the spacecraft would have to carry much more fuel. The Mars Odyssey Orbiter is only the third spacecraft to use aerocapture. Before that, only the Mars Global Surveyor (1997) and the Mars Climate Orbiter (lost in 1999) had used it. Don't confuse aerocapture with aerobraking. While similar, aerobraking uses atmospheric drag to slow down a vehicle that will land on a planet's surface. Aerocapture is used to place a spacecraft into orbit.

The orbiter's final operational altitude is about 250 miles (400 km) above Mars in a sun-synchronous polar orbit. In the following two years, the orbiter maps the planet's surface and takes measurements about radiation and elemental composition.

The Mars orbiter is just one in a series of orbiters, rovers and surveyors that NASA plans to launch toward Mars in an effort to learn as much as possible about the planet before sending a human mission there. In the next decade, the U.S. space agency will launch at least one Mars exploration spacecraft in every odd numbered year.

NASA's Mars Exploration Plan
  • April 2001 - Mars Odyssey Orbiter begins journey to Mars to conduct analysis of the planet's elemental composition. It reaches Mars on October 23, 2001.
  • 2003 - Twin Mars Exploration Rovers search for water, past or present, on Mars.
  • 2005 - The Mars Reconnaissance Orbiter launch. Its goal is to analyze the planet's surface at new scales to find hints of water. It will measure landscapes at a resolution of 8 to 10 inches (20 to 30 cm), which is good enough to observe rocks the size of beach balls.
  • 2007 - NASA launching a mobile science laboratory to advance surface measurements.
  • 2011-2016 - The Martian sample return mission is the most ambitious of NASA's plans. It calls for a spacecraft that can land on Mars, scoop some of the soil and then launch itself back toward Earth.
  • 20xx - Humans will take their first steps on a foreign planet.

For more information on Mars Odyssey and related topics, check out the links on the next page.