Clear skies, Scott.

Today Scott Carpenter died from complications after suffering a stroke. He was 88 years old.  He was the second American to orbit the earth. His only spaceflight, with a Mercury capsule called Aurora 7,  ended in a bit of a messy situation when he overshot his designated landing spot by several hundred kilometres. because of a malfunctioning horizon scanner he used a lot of manoeuvring fuel during his orbits but also suffered several malfunctions at re-entry that caused him to push the retro rockets manually, which occurred almost a second too late. The thrust of the retro's also was not optimal and all of this caused the overshoot. He also was the one that spoke the words "Godspeed, John Glenn" when Glenn lifted off as the first American to orbit the earth.
After a motorcycle accident in 1964 he suffered loss of function of one of his arms and that resulted into losing his chance to return into space. But I presume his not so perfect Mercury flight also might have played a role in the decision to take him off the list for another flight.
He turned into an aquanaut for the Navy in the late sixties, working in underwater laboratories.

Malcolm Scott Carpenter © NASA

Carpenter was one of the first to explore the New Ocean and just for that reason alone he already was a pioneer and a vanguard. He might not have been NASA's ideal astronaut in that time but he certainly was a tough man, having to endure the gruesomeness of those first astronaut's medical tests and become one of the Original Seven. His old colleagues, Alan Shepard, Gus Grissom, Gordo Cooper, Wally Schirra and Deke Slayton already passed away earlier. 

This leaves his good friend John Glenn the only one still alive of the Original Seven.