NASA's Mariner 4 Space Probe
By | August 2, 2021
Technicians working on Mariner 4 before launch. (NASA JPL)
Space, despite existing thousands of miles away, holds a special place in human history. Whether it’s stargazing, Star Wars, or just the great unknown of the final frontier, humans have spent countless hours thinking about space. The United States and the former USSR, of course, engaged in an actual race to space that, at the time, appeared to decide the fate of the world. While Mariner 4 did not participate in the much-ballyhooed march to the moon, the competition between the Russians and Americans still ran hot.
The mission also opened humanity’s eyes to yet another awe-inspiring planet just a few million miles away and debunked many theories. Without Mariner 4 our understanding of Mars would have remained woefully incomplete.
NASA's Mariner spacecraft. NASA)
What We Thought
In the late 19th century an astronomer named Giovanni Schiaparelli claimed to see linear patterns on the Red Planet, which he dubbed canalis. An unfortunate translation led to the belief that canals and potentially intelligent life existed on Mars. Once someone realized canalis didn’t mean canals, the idea fell out of favor.
Still, the concept birthed many science fiction stories and also made its way into the culture. In the 1960s, the best telescopes could only make out an ever-changing landscape, which gave life to the theory that small plant life grew on the fourth planet from the sun. More critically, the United States and the former USSR continued to lock horns in the pursuit of space.
The tense launch of Mariner 4. (NASAMarsExplorationProgram).jpg
Missions To Mars
Between 1960 and 1964 seven different space crafts attempted the more than 100 million mile journey to Mars. The USSR sent five separate ships during that period and they all failed. NASA launched Mariner 3 just a month before Mariner 4 and watched as it sailed into space, incapable of transmitting home. After hastily making adjustments to Mariner 4, NASA launched with just two days left in the mission’s window from Cape Canaveral, Florida on November 28th, 1964.
Anxious and exhausted scientists waiting for signals from Mariner 4. (NASA JPL)
First Transmission From Deep Space
After successfully jettisoning its payload, unlike Mariner 3, Mariner 4 became the first spacecraft to transmit from deep space. As it hurtled through space for 228 days over millions and millions of miles, NASA scientists anxiously awaited its rendezvous with the Red planet. As planned the craft flew within 10,000 km of Mars and snapped the first pictures.
Via its two antennas, Mariner 4 could transmit at a combined 40 bits per second, also known as dial-up speeds. Still, you got to give the craft credit for range. Mariner 4 sent 200 by 200 pixel photos of Mars over 100 million miles. Each picture took about 10 hours to transmit.
Mariner 4's historic Mars photo shoot. (caltech)
Fact-Finding
While the pictures transmitted back in 1964 pale in comparison to the images we have today, they did provide necessary facts to dispel many fictions. As NASA stated, "Man's first close-up look at Mars had revealed the scientifically startling fact that at least part of its surface is covered with large craters. Although the existence of Martian craters is clearly demonstrated beyond question, their meaning and significance is, of course, a matter of interpretation.''
No canals, no intelligent Martians, not even plants. The New York Times wrote that Mars is "probably a dead planet." Although many were disappointed that we lacked neighbors in our solar system, the mission taught us a great many facts about our nearest planet. We learned its relative age thanks to the crater photos, along with temperature (minus 100 celsius) and radiation belt.
The mission became one of the early crowning achievements of NASA. The plucky little probe was even successfully reactivated two years after the mission and served as support for Mariner 5’s mission to Venus!
