Twenty-five years ago, on July 20, 1976, NASA’s Viking 1
lander soft-landed on the surface of Mars, becoming the first
successful mission to land on the Red Planet, as well as the
first successful American landing on another planet.

With a second lander later joining the first on the surface
and with two orbiters circling the planet, the Viking project
changed our understanding of that alien world. Its treasure
trove of images and data covering the entire Martian globe
remains a valuable scientific resource for the study of Mars.

Thursday, July 19, NASA Administrator Daniel S. Goldin
delivers the keynote address at “Continuing the Quest —
Celebrating Viking and Looking to the Future of Mars
Exploration,” a symposium hosted by Lockheed-Martin Corp. at
the National Geographic Society’s Grosvenor Auditorium,
Washington, DC, from 1 p.m. to 5:30 p.m. EDT.

NASA’s Langley Research Center, Hampton, VA, hosts a panel
discussion, titled “Viking: The First Encounter,” at
Langley’s Reid Conference Center, Friday, July 20, from 1:30
p.m. to
3 p.m. EDT. This event will be broadcast live on NASA
Television.

The Viking 1 lander operated on the Plain of Chryse (Chryse
Planitia) until November 1982. The Viking 2 lander set down
on the Plain of Utopia (Utopia Planitia) on Sept. 3, 1976,
and operated until April 1980. The two landers took 4,500
unprecedented images of the surrounding surface and more than
three million weather-related measurements, while the two
orbiters took 52,000 images representing 97 percent of the
Martian globe.

Viking will probably be most remembered for its search for
life on Mars. Each lander contained a suite of biology
instruments designed to detect evidence of life in the
Martian soil. Scientists concluded that the Viking
experiments found no evidence of life at either landing site,
but didn’t rule out the possibility that life may have
existed in the past or may still exist in other, more
hospitable, places.

“The Viking landing sites are extremely dry desert
environments where it would be unlikely to find present-day
biological activity on the surface,” said Dr. Jim Garvin,
Mars Program Scientist at NASA Headquarters, Washington, DC.
“Other sites on Mars, such as nearer the polar caps or other
places where liquid water may be found, are far more likely
places to look for signs of present or past life. Our long-
term plans call for missions to find liquid water on or under
the surface, which will be the best places to begin a search
for signs of life.”

NASA’s Langley Research Center was responsible for managing
Project Viking. “We didn’t really knows what Mars was all
about. Mars had been examined from orbit by the Mariners and
we had a pretty good picture, but the images were on the
scale of a football field,” said Viking Project Manager James
Martin. “That was the smallest thing we could see and that’s
not very distinct when you consider the landers are only in
the order of six or eight feet across. We didn’t have the
slightest idea what was on the surface in that scale.”

In April 1978, Langley turned Project Viking over to NASA’s
Jet Propulsion Laboratory (JPL), Pasadena, CA. Today, JPL
manages the Mars Exploration program, a two-decade-long
effort to answer fundamental questions about Mars’ early
evolution and its ability to support life.

Since Viking, NASA’s missions to Mars have included the ill-
fated Mars Observer, the successful Mars Pathfinder lander
and Sojourned rover, the prolific Mars Global Surveyor (still
operating in orbit around Mars), and the Mars Climate Orbiter
and Mars Polar Lander, both of which failed as they neared
Mars. The 2001 Mars Odyssey explorer is more than halfway to
the Red Planet and is due to arrive in orbit on Oct. 23.

In 2003, NASA plans to launch twin geology-laboratory rovers
to the surface, each the size of a desk and capable of
travelling up to 110 yards a day from their landing site.
Other missions, including landers and orbiting missions, will
follow every 26 months.

More information about NASA’s Mars Exploration program is
available on the Internet at:
http://mars.jpl.nasa.gov