McArthur has an aerospace engineering degree from UCLA and a doctorate in oceanography from UC San Diego. At the Scripps Institution of Oceanography, McArthur used an algorithm to develop geoacoustic models that could describe shallow water waveguides. In space, her time was spent conducting  conduct research experiments in medical technology and human health.

McArthur’s time in space was memorable for the good and the not-so-good.

Among the upbeat milestones: four spacewalks to enhance the station’s solar power, a movie-making visit by a Russian film crew, a birthday cake delivery and the first-ever space harvest of chile peppers, which were quickly turned into tacos (some of them, at least).

Before leaving the neighborhood, the four took a spin around the space station, taking pictures. This was a first for SpaceX; NASA’s shuttles used to do it all the time before their retirement a decade ago. The last Russian capsule fly-around was three years ago.

McArthur’s most recently Tweeted photos shared some of the fun moments the crew had — joking around with their stuffed penguin friend, Guin-Guin, and some spectacular views of Arches National Park and the aurora borealis that “felt like a gift.”