When Apollo 9 astronaut Russell "Rusty" Schweickart opens the front door of his home in Sonoma, it's obvious he's on a mission.
He runs and grabs a pair of binoculars, then sprints up the stairs to join his wife, Nancy Ramsey, on the second floor.
"There's an owl in my owl house!" he shouts excitedly, pointing out a Great Horned Owl roosting in a box high in an oak tree. "This is our first owl."
Slim and fit at 77, Schweickart has lived in Sonoma since 2007, where he spends his well-earned retirement years playing golf, travelling and supporting projects such as the Green Music Center.
The former astronaut, whose space voyage in 1969 paved the way for the first lunar landing, has never looked at Earth in quite the same way since circling it 151 times, through 151 sunrises and sunsets, 44 years ago this month.
As part of the three-man Apollo 9 team, Schweickart spent 10 days in low Earth orbit in March 1969. He was the first person to pilot the Lunar Module, and he tested the life-support system that would help put men on the moon a year later.
"We did as much as we could (to test) all that would take place in a lunar orbit," he said. "We couldn't go down to the surface, but I went outside with the backpack that was used to run around on the moon."
During that spacewalk, Schweickart got a gift from his crew members, James McDivitt and David Scott: a small window of time with nothing to do.
"Dave was taking pictures of me, and Dave said the camera jammed," he recalled. "So I had a famous five minutes, and I decided that this is my time to be a human being."
During that time, Schweickart gazed down at the green and blue planet from his cosmic perch and, like others before and after him, was overwhelmed by its glowing beauty and the awe-inspiring perception of the interconnectedness of all life.
But Schweickart didn't get a chance to articulate his feelings until five years later, when he gave a talk, "No Frames, No Boundaries," at a conference on Long Island.
"When you go around the Earth in an hour and a half, you begin to recognize that your identity is with that whole thing," he told the crowd of 60 people. "And that makes a change."
This off-the-cuff talk, in which he narrates the nuts and bolts of the Apollo 9 mission as well as what it meant for humanity to look back at itself, was a life-changing moment for the down-to-earth astronaut.
"I started to talk and went on for 40 minutes," he said. "And when I got done, half the people were crying, and I was crying, too."
In a way, Schweickart's most important contributions have come after that historic 1969 flight. Having sufferered nausea from space sickness — a common reaction as the body tries to adapt to weightlessness — he volunteered to become part of a research study.
"We needed to learn more about it so that we didn't needlessly risk anyone on subsequent flights," he said. "Hence, I was a guinea pig while my buddies went to the moon."
He also served as back-up commander of the first Skylab space-station mission in the spring of 1973, developing a plan for erecting an emergency solar shade and saving the space station after its thermal shield was lost upon launch. NASA honored him with the NASA Distinguished Service Medal in 1969 and the Exceptional Service Medal in 1973.