This monograph describes the National Aeronautics and Space Administration's program to explore the planet that most nearly resembles the earth and the search for life on the surface of Mars that the Vikings are scheduled to begin in 1976.

This is a completely updated and revised version of a monograph published in 2002 by the NASA History Office under the original title Deep Space Chronicle: A Chronology of Deep Space and Planetary Probes, 1958-2000. This new edition not only adds all events in robotic deep space exploration after 2000 and up to the end of 2016, but it also completely corrects and updates all accounts of missions from 1958 to 2000--Provided by publisher.