Sixty years ago, NASA’s Mariner 4 became the first spacecraft to fly by Mars, capturing the first close-up images of any planet beyond Earth. The mission revealed a barren, cratered surface that dispelled notions of alien civilizations and sparked the era of Mars exploration.
For decades, humans have been fascinated with Mars, often seeing it as an untouchable, mysterious world. However, scientists had long used telescopes on Earth to study the Red Planet from afar. Before Mariner 4’s historic journey in 1965, astronomers trained their telescopes on Mars when it was at its closest and brightest, passing only 35.1 million miles away.
The spacecraft’s images showed a desolate landscape with craters upon craters – no signs of canals or life. The revelation sparked excitement among scientists, who saw an opportunity to study the Martian surface, which had been largely untouched for 2 billion years. This surface might hold clues about Earth’s early history and the origins of our solar system.
Mariner 4 also revealed that Mars has a thin atmosphere, with pressure less than 1% that on Earth’s surface, making it inhospitable to liquid water. The mission’s success marked one of the most brilliant engineering and scientific achievements in space exploration history.
Source: https://science.nasa.gov/mars/triumph-of-mariner-4