Mars Odyssey (NASA). Results. Mars Express (ESA) European Space Agency

NASA's Hubble Space Telescope took the picture of Mars on June 26, 2001, when Mars was approximately 68 million kilometers (43 million miles) from Earth — the closest Mars has ever been to Earth since 1988.

2001 Mars Odyssey (NASA)

2001 Mars Odyssey is part of NASA's Mars Exploration Program, a long-term effort of robotic exploration of the red planet. The opportunity to go to Mars comes around every 26 months, when the alignment of Earth and Mars in their orbits around the sun allows spacecraft to travel between the two planets with the least amount of energy.

2001 Mars Odyssey launched on April 7, 2001, and arrived at Mars on October 24, 2001

Results

For the first time, the mission globally mapped the amount and distribution of many chemical elements and minerals that make up the martian surface.

Maps of hydrogen distribution led scientists to discover vast amounts of water ice in the polar regions burried just beneath the surface.

Odyssey also recorded the radiation environment in low Mars orbit to determine the radiation-related risk to any future human explorers who may one day go to Mars.

Cost

$300 million

Mars Express (ESA) European Space Agency

Image from Mars Express (2006)

Mars Express set off on 2 June 2003

Results

The Mars Express imaged the entire surface at high resolution, produced a map of mineral composition, determined the effect of the atmosphere on the surface.

Due to images, scientists were able to design and present three-dimensional models of Martian landscapes.

Cost

? 300 million