Rubins, of NASA, and Noguchi, of the Japanese Space Agency, installed a device on an airlock cover to prevent it from blowing out when a hatch is opened. The two also attached new apparatus that will hold upgraded solar panels when they are installed over the summer.

The outing was the fourth career spacewalk for both Rubins and Noguchi and the 236th spacewalk at the space station.

Rubins reported a pinpoint abrasion on one of her gloves after several hours in space. She was concerned enough to stay close to Noguchi after the discovery, but her spacesuit didn't leak.

Rubins, 42, is a microbiologist whom NASA selected in December as one of 18 astronauts who could become the first woman to walk on the moon during planned Artemis missions.

She is recognized as the first person to conduct in space a sophisticated genetic scientific technique known as DNA sequencing.

At the time of the Artemis announcement, Rubins said living in space is still a fantastic notion for her, but she also views the space station as a second home. The current mission is her second there.

"We might have people on the planet soon, able to look up and know that there are humans on the moon again and that we've done this as a joint international collaboration," Rubins said in a recorded NASA interview in December.

Noguchi, 55, is an aeronautical engineer who has flown on three spacecraft -- the space shuttle, a Russian Soyuz capsule and SpaceX's Crew Dragon capsule. He said Crew Dragon, which was launched from Florida in November, is the best of the three.

The space station, which spans the length of a football field, is equivalent to a five-bedroom home with a gym, two bathrooms and a 360-degree bay window -- the cupola -- that allows views of Earth.

Large arrays of solar panels power its systems, while liquid propellant rocket engines keep it from losing altitude.

The space station, which cost more than $150 billion to build and costs NASA over $3 billion annually, flies at more than 250 miles above the Earth at more than 17,000 mph.