How many astronauts can you name without consulting Google or Wikipedia?

Neil Armstrong and Buzz Aldrin are easy. They were the first men on the moon. You should probably also remember their Command Module pilot, Michael Collins. But he wasn’t one of the first on the moon, so he comes less easily to mind.

Christina Koch, who returned to Earth on Thursday from the International Space Station, might be another name you’ll come to remember. She and Jessica Meir executed the first all-woman spacewalk. Although Ms. Koch performed six spacewalks during her mission, set a duration record for time in space and contributed enormously to space science, that October spacewalk will be what gets her into history books.

In the same way, Sally Ride is known for being the first American woman in space, but not for her work in the development of the space shuttle’s robotic arm. In all of these cases, being first was a matter of timing, not something that was under the direct control of the astronauts credited for their trailblazing.

It’s not as if there was a race to be on the first all-female spacewalk. In fact, the opposite might be said to be true.