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THE MARS MARINER MEDIA EVENT
Shown above: The media frenzy at JPL, July 14, 1965.
On July 14 and 15, 1965, the world's attention centered on Mariner 4 when it began transmitting a series of 22 grainy black & white pictures of the Martian surface as it made its closest approach to Mars. Launched on November 28, 1964, the spacecraft performed the first successful flyby of Mars and gave us the first images ever taken from deep space of another planet—revealing a cold, cratered, moon-like surface, rather than an Earth-like planet as originally assumed would be the case.
It took Mariner 4 approximately 25 minutes to take the 22 pictures as it flew passed the planet.And the transmission of data was very slow; it would take over 8 hours to complete one picture. Though blurry by today's standards, and only capturing a very small portion of the Martian surface, the images nevertheless gave scientists a brief glimpse of one of the more ancient regions of the planet, revealing craters that ranged anywhere from 3 to 75 miles (5 to 120 kilometers) in diameter and were estimated to be between 2 and 5 billion years old. Later missions would reveal a planet of varied environments, including great volcanoes and valleys.
Shown above: Mars image #11 taken by Mariner 4 showing the largest (120 kilometers) and smallest (5 kilometers) craters seen on any of the photos. This was also the photo chosen, enlarged, and framed to present to President Lyndon B. Johnson at the White House in July 1965.
Three members of Caltech's faculty were important to the success of the mission's imaging experiment.
Shown above: Robert Leighton (seated), reviewing Mars images taken by Mariner 4.
Physics professor and Caltech alumnus Robert Leighton—who in the 1950s had done work at Mount Wilson with developing an image stabilization device and had photographed Mars through the 60-inch telescope and created actual movies of Mars rotating—helped guide and develop JPL's first digital television system for use in deep space and would lead the imaging experiment team.
Shown above: Robert Sharp with Mariner 4's Mars images on the table before him.
Robert Sharp, also a Caltech alumnus and the Chairman of Caltech’s Geological Sciences Division at the time, being an expert in geomorphology, also joined Leighton’s team. Once the pictures were transmitted to Earth, Sharp would be in charge of interpreting them. In his honor, on March 28, 2012, NASA would name a mountain "Mount Sharp" on Mars—located at the center of Gale Crater, where in August 2012 JPL’s rover Curiosity successfully landed.
Shown above: Bruce Murray in discussion, analyzing the data.
And Caltech’s first Associate Professor of Planetary Science Bruce Murray—who began his career at Caltech by using big telescopes, such as the 200-inch Hale telescope at Palomar to observe the Moon and Mars—would complete the team by using the pictures taken by Mariner 4 to work out the geologic history of Mars.
Shown above: Model of Mariner 4 (NASA photo).
Considered one of the great successes of the early U.S. space program at the time, Mariner 4 would far outlast its original 8-month mission, remaining in solar orbit about 3 years, during which time it would continue to send useful scientific data on solar wind as well as make coordinated measurements with its sister spacecraft Mariner 5. The information collected would lead scientists and engineers to conclude that the Martian atmosphere and surface were fully exposed to solar and cosmic radiation. Communication with Mariner 4 would be terminated on December 21, 1967.
All totaled, there were 10 Mariner spacecraft launched between 1962 and 1973, with the purpose of visiting and collecting data on our nearest neighbors—Venus, Mars, and Mercury. The Mariner program would prove important in laying the groundwork for all future exploration of our solar system. – LK
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