Missions to Mars

Throughout history, humankind has looked skyward to Mars and wondered: Could it be another Earth? Mars has a tilted axis, an atmosphere, and a day only forty minutes longer than that of Earth. With so many surface similarities, even without clear evidence of life in Mars’s past, there is every reason to believe there is life in the Red Planet’s future.

Telescopes were pointed toward Mars as early as the 17th century, but it was Mariner 4—launched in 1965 on a Lockheed Atlas-Agena D rocket—that provided the first close-up images of the red planet, which indicated a cold, dead world. In 1971, Mariner 9 became the first Earth-based craft to achieve orbit around Mars, providing even more images of craters, mountains, polar deposits and extinct volcanoes. Though successful missions, the Mariners offered more questions than answers, and it became clear that the only way to solve these mysteries would be to land someone—or something—on the planet’s surface.

In 1969, NASA chose Martin Marietta as the principal industrial contractor for Project Viking. Project Viking would include an orbiter that would study Mars from the sky, as well as two landers that would study the surface of the red planet. Martin Marietta was tasked with designing and building two Mars landers, the entry systems to place the landers on the Marian surface and the Titan III and Centaur rockets needed to launch the Viking landers from Earth.

Built by the Denver astronautics team, the Los Angeles Times dubbed the Viking landers “a triumph of function over form … as bizarre as any Martian machine ever conceived by a science-fiction writer.” The landers were 1,300 pounds with six sides covered in tanks, antennas and funnels. The scientific equipment inside the landers included cameras, nuclear power generators, on-board biology and chemistry labs and even the basics like a shovel and sifter on the end of an extendable arm. Among other objectives, Viking’s mission was to gather and test the soil of another world. Since a radio transmission from Earth to Mars and back could take more than 37 minutes, computer programming would be critical, and Viking would be the most automated mission ever taken on.

On July 20, 1976 at 1:33 A.M., on the seventh anniversary of the very first moon landing, the first of two Viking landers separated from the orbiters. As anticipated, it took 19 minutes for that information to reach Earth. Huddled around the control room at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., the lag between action and information was stressful for all involved. NASA’s Al Hibbs downplayed the lag in communication by reporting, at nearly 5 in the morning, “Viking should be on the surface of Mars by now, one way or another.”

By 5:12 a.m., NASA finally received confirmation that the lander had achieved safe touchdown. George Sands of the Jet Propulsion Laboratory said, “The indicated landing time is evidently seventeen seconds later than the expected signal. Not bad when you’re dealing with an automated spacecraft across two-hundred and twenty-five million miles.” Newspapers and magazines around the world would soon publish the first pictures taken from the surface of Mars.

A few weeks later, the second Viking lander touched down on Mars, and the two craft continued to take pictures, sample soil and send data back to Earth until their missions were complete in 1982.  A resounding success, the Viking landers transmitted back more information about Mars than science had known about the planet. Though the search for life was inconclusive, Viking discovered evidence of dry river valleys and past rainfall—and where there’s water, there could be life.

Many years would pass before we would return. The Mars Global Surveyor, an orbiter built at Lockheed Martin’s Denver astronautics plant, marked the first successful return to Mars since Viking in 1996. Despite finding further evidence of water on the Martian surface, it was followed by a string of unsuccessful missions. Some were canceled and some craft simply didn’t make it to Mars as planned, like the Mars Surveyor ’98 mission, which entered the atmosphere at an improper angle and disintegrated. With few exceptions, the 1980s and ’90s were challenging periods for the continued exploration of Mars.

Fittingly, a new era in Mars exploration came at the dawn of a new century, when the 2001 Mars Odyssey mission discovered huge deposits of hydrogen near the northern polar region of Mars. Odyssey also became the primary means of communication between NASA and the various Mars rovers exploring the planet’s surface. Odyssey was so successful, its mission has been extended four times. It’s still running in 2012, and shows no signs of stopping.

Mars exploration continued to focus on following the water. In 2006, the Mars Reconnaissance Orbiter produced high-resolution images and helped determine the landing site for Lockheed Martin’s Phoenix Mars Lander. In 2008, the Phoenix’s arrival in the Green Valley region exposed ice just below the planet’s surface, confirming the evidence once and for all: there was water on Mars.

The recent landing of the Mars Science Laboratory rover is the latest step in exploration. Built by the Jet Propulsion Laboratory, the Curiosity rover is the most advanced robot ever sent to a planet. Lockheed Martin pulled from years of experience, dating back to Viking, to build Curiosity’s protective aeroshell capsule.

Other Lockheed Martin craft will soon will be en route. The Mars Atmosphere and Volatile Evolution, or MAVEN mission, will be an orbiter destined for in-depth study of the atmosphere.

Just as the race to the moon defined space exploration of the 20th century, it will be a manned mission to Mars that will be the crowning achievement of space exploration in the 21st century. Lockheed Martin is now hard at work on the Orion Multi-Person Crew Vehicle, the next generation of manned spacecraft. Beginning test flights in 2014, Orion looks more like Apollo-era craft than the space shuttles it will replace.

Humankind is exploratory by nature, and Mars is the next frontier of exploration. At the time of Viking 1’s successful landing on the surface of Mars, NASA’s Viking flight team scientist Dr. Gerald Soffen said, “We don’t really know what lies ahead. As each day passes on the surface, we learn new questions to ask.”

Those words remain true today.

Sources and Additional Reading

• Harwood, William B. Raise Heaven & Earth. New York: Simon & Schuster, 1993.
• http://www.astronautix.com/craft/voyr1973.htm, accessed 16 July 2012.
• Senate Committee on Aeronautical and Space Sciences, NASA Scientific and Technical Programs hearings, 28 February 1961 and 1 March. 1961.
• Horowitz, Klein, Lederberg, Levin, Oyama, Rich: “The Viking Mission search for life on Mars”. http://profiles.nlm.nih.gov/ps/retrieve/Narrative/BB/p-nid/32/p-docs/true, accessed 14 July 2012
• Alexander, George: “Viking Science: Tantalizing; Viking Scientists: Cautious.” ftp://ftp.hq.nasa.gov/pub/pao/reports/1999/MCO_report.pdf, accessed 14 July 2012
• Interview with Gary Napier, The History Factory, 28 June 2012. Chantilly, Virginia, transcript.