The last survivor of the Apollo 7 mission, Walter Cunningham, died on Tuesday at the age of 90. After serving in the US Navy and Marine Corps, Cunningham joined NASA and took part in the Apollo program's first crewed flight.

Cunningham was an "integral to our Moon landing's program success," according to NASA. Cunningham died in a hospital from a fall.

The first spaceflight after the Apollo 1 tragedy was called Apollo 7. Human-crewed spaceflight was put on hold for 21 months after Apollo 1. The crew spent a lot of time studying the design and construction of the Apollo command and service modules to make sure they didn't have another tragedy. After almost 11 days in space, the crew splashed down on Earth. The first humans to walk on the moon were helped by Apollo 7 and Apollo 11.

Four astronauts laughing and looking to the horizon in a 196
Left to right: Walter Schirra, Donn Eisele, Walter Cunningham, Dr. Donald E. Stullken

Cunningham retired from NASA in 1971 and began his career as a public speaker, radio host, offshore engineer and venture capital investor. He became an ardent climate change denier. Cunningham went through a laundry list of talking points from the fossil fuel industry while speaking to Forbes. Climate change is real and we have less than a year to avoid catastrophe.

Cunningham believes that we lived in the good old days. The golden age of manned spaceflight was when we were living. We have been in space for over four decades. We went from barely flying to jet transport in 40 years. Since we went into space, we haven't moved that much. There won't be another time like that again. It won't be the same when we go to Mars. I feel lucky that I was a small part of it.