American astronomer and planetary scientist Steve Squyres, the principal scientist in charge of Mars exploration rovers Spirit and Opportunity, explains how he fell in love with Mars and why humans need to go there.
Photo: NASA/Jet Propulsion Laboratory Martian sunrise at Phoenix landing site on Mars ▲ Photo: NASA/Jet Propulsion Laboratory Martian sunrise at Phoenix landing site on Mars ▲ Photo: NASA/Jet Propulsion Laboratory Martian sunrise at Phoenix landing site on Mars ▲ Photo: NASA/Jet Propulsion Laboratory Martian sunrise at Phoenix landing site on Mars ▲ Photo: NASA/Jet Propulsion Laboratory Martian sunrise at Phoenix landing site on Mars ▲ Photo: NASA/Jet Propulsion Laboratory Martian sunrise at Phoenix landing site on Mars ▲ Photo: NASA/Jet Propulsion Laboratory Martian sunrise at Phoenix landing site on Mars ▲ Photo: NASA/Jet Propulsion Laboratory Martian sunrise at Phoenix landing site on Mars ▲ Photo: NASA/Jet Propulsion Laboratory An image of the Spirit rover is supperimposed on a view of the sunset at Gusev crater on Mars. ▲ Photo: NASA/ Jet Propulsion Laboratory An approximate true-color picture of one of the walls of Victoria Crater in Mars, taken by the Opportunity rover. ▲ Photo: NASA/Jet Propulsion Laboratory-Caltech/Cornell Simulated image of Opportunity inside Endurance Crater ▲ Photo: NASA/Jet Propulsion Laboratory A 360-degree panorama taken by Opportunity on its 12-km trek to Endeavor crater. ▲ Photo: NASA/Jet Propulsion Laboratory A false-color panorama taken by Opportunity on its 12-km trek to Endeavor crater. ▲ Photo:NASA/Jet Propulsion Laboratory-Caltech, Cornell Synthetic image of Spirit on "Husban Hill" on Mars ▲ Photo: NASA/Glenn Research Center Planet Mars ▲ Photo: NASA/Kennedy Space Center Apollo 11 liftoff ▲ Photo: NASA/ Glenn Research Center Apollo astronat on the moon ▲ Photo: NASA/ Johnson Space Center Astronaut John Glenn poses in Mercury Spacesuit in 1962. ▲ Photo: Matt Hintsa Ho Plaza, Cornell University, Ithaca, NY ▲ Photo: NASA Viking Orbiter 1 spacecraft ▲ Photo:NASA/Kennedy Space Center Artist drawing of the Viking spacecraft ▲ Photo: NASA/ Langley Research Center This Viking Orbiter 1 image shows a sunrise over one of Mars high plateau regions. The white areas are bright clouds of water ice. ▲ Photo: NASA/Jet Propulsion Laboratory Viking Orbiter 2 captures a large dust storm over Mars. ▲ Photo: NASA/Jet Propulsion Laboratory Three Viking images make up this image of the Memnonia Fossae region of Mars. ▲ Photo: NASA/ Jet Propulsion Laboratory Earth and Mars comparison ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA, M.Wolff, J.Bell, S.Lee NASA's Hubble Space Telescope captured these sharp views of Mars during the planet's close approach to Earth in 1999. ▲ Photo: NASA and G.Bacon An artist's conception of an acient gas-giant planet surrounded by a sea of stars ▲ Photo:NASA, ESA and G.Bacon An artist illustration of three extrasolar planets ▲ Photo: NASA/Jet Propulsion Laboratory Artist conception of a distant hypothetical solar system ▲ Photo: NASA, ESA, the Hubble Heritage Team One of the few planetary nebula in our galaxy that's nested inside an open start cluster ▲ Photo: NASA/P.DiMare Artist concept of astronauts walking on Mars ▲ Photo: NASA/Jet Propulsion Laboratory Artist illustration of a NASA Mars rover ▲ Photo: NASA/Jet Propulsion Laboratory Spirit uses its robotic arm to examine a Martian rock. ▲ Photo:NASA Gemini VI in orbit above Earth in 1965 ▲ Photo:NASA/Johnson Space Center Astronaut John Glenn photographed this orbital sunset during a Mercury-Atlas 6 flight. ▲ Photo: NASA/Johnson Space Center Apollo captures Earth rise from the Moon. ▲ Photo:NASA/Jet Propulsion Laboratory A mosiac of Mars composed with Viking Orbiter 1 images ▲