Free The Case for Mars by Robert Zubrin

biology experiments came to a close. Orbiter 2’s last transmission came on July 25, 1978, followed by the demise of Lander 2 on April 11, 1980, nearly two years later. Orbiter 1 sent its last signal on August 17, 1980, while Lander 1 signed off on November 5, 1982.
    The Soviet space program attempted two launches in 1988 to explore Mars and its moon Phobos that met with disappointment, continuing a streak of bad luck that has plagued every Soviet or Russian Mars mission. (Out of more than fifteen attempts, none has been successful.) The United States’ Mars program has also had to deal with failures. The Mars Observer spacecraft carried seven instruments intended to investigate Mars over the course of a Martian year. The mission would “rewrite the books” on Mars, or so researchers hoped. But just days before the spacecraft was due to enter orbit around the Red Planet, it fell silent. In attempting to reconstruct what may have happened, engineers have surmised that a fuel line ruptured as the spacecraft prepared to fire up its engines to slip into Mars’ orbit. Whatever the cause, after a seventeen-year hiatus, America’s exploration of Mars appeared headed for the deep freeze.
    Fortunately, instead of using the demise of Mars Observer as a pretext for thrashing NASA’s Mars exploration budget, members of Capitol Hill looked kindly upon continuing the legacy of exploration that the Vikings exemplified, though with a twist. With a new focus on “faster, cheaper, better” methods of accomplishing planetary exploration, NASA has fashioned a decade-long program of Mars exploration out of the Mars Observer failure. Instead of launching a single massive spacecraft to the Red Planet, American plans now call for a series of small spacecraft to orbit and land on Mars. This program started in late 1996 with the launch of the Mars Global Surveyor spacecraft and the Mars Pathfinder mission. About half the size of Mars Observer , the Surveyor began mapping the Red Planet from polar orbit in January 1998. Among its discoveries to date have been altimetry data revealing a large basin of depressed and relatively uncratered terrain in Mars’ northern hemisphere that is flatter than anything on Earth except for the sea bottoms, indicating the previousexistence of a northern ocean. Mars Pathfinder landed on Mars on July 4, 1997, with the help of parachutes, braking rockets, and airbags. Surviving several 40 to 60 miles per hour bounces along the surface, Pathfinder opened up and released a tiny rover (dubbed Sojourner after antislavery heroine Sojourner Truth). Sojourner then traveled for two months about the Ares Valles runoff channel landing site, collecting geological information and making the notable water-indicative discoveries of rounded cobbles and conglomerate rocks. An additional lander (targeted to the south pole) and orbiter were launched to Mars in 1998, and plans call for additional spacecraft launches in 2001, 2003, and 2005.
    While the U.S. robotic Mars exploration program is moving ahead, budgetary difficulties and bad luck have thrown the Russian program into chaos. Russia’s latest attempt, entitled Mars 96 , aimed to place a spacecraft in orbit around Mars, as well as two small science stations and two ground penetrators on the Martian surface, but was thwarted by a launch vehicle failure in the fall of 1996. This caused the indefinite postponement of a second mission, Mars 98 , which was to deliver an orbiter, rover, and balloon to the planet. The Russian Marsokhod rover would have dwarfed the American Pathfinder rover and, instead of venturing just 10 meters away from its landing site, could have logged nearly 50 kilometers. Trailing an instrument-laden “snake,” the balloon, a product of the French space agency CNES, was designed to soar as high as 4 kilometers into the Martian atmosphere during the day, but settle toward the ground during the Martian night. Designed for a ten-day flight, the balloon would