Already reeling from the passing three weeks ago of former astronaut Bruce McCandless, the worldwide community of astronomy and space was dealt a double blow this past weekend, with the passing of, not one, but two, of its more notable representatives.

While the two individuals in question are known for dramatically different contributions to the field, those contributions have nevertheless been most important in furthering our understanding of the universe around us.

Former astronaut John Young was born in San Francisco in 1930 but spent most of his childhood in Orlando, Florida. After graduation from Georgia Tech University in 1952 he was commissioned in the U.S. Navy, and later completed flight school and eventually became a Navy test pilot. In 1962 he was one of nine astronauts selected in NASA’s Group 2, the first crop of astronauts following the original Mercury 7.

Young’s first space flight was the Gemini 3 mission, the first manned mission of the Gemini program, in March 1965, wherein he and veteran astronaut Gus Grissom orbited the Earth three times. He would return to space in June 1966 as part of the crew of the Gemini 10 mission (along with Michael Collins, who would later play the role of Command Module Pilot for Apollo 11); over a space flight that lasted slightly less than three days the crew rendezvoused with two separate Agena vehicles and docked with one of them.

Young would be one of three astronauts who would make two different trips to the moon. His first trip was as part of the crew of the Apollo 10 mission in May 1969, a dress rehearsal for the Apollo 11 landing mission two months later, and which tested the lunar module in lunar orbit; Young was the Command Module Pilot. He would return to the moon in April 1972 as commander of the Apollo 16 mission, wherein he and fellow astronaut Charles Duke spent three days on…