While undertaking health and scientific investigations, NASA astronauts on the International Space Station are preparing for a June 9 spacewalk to install new solar arrays. The weather may delay Kennedy Space Center’s launch of a SpaceX Dragon cargo ship carrying solar panels.

At the end of the workweek on the International Space Station (ISS), Expedition 69 focused on science and spacesuits. The orbiting outpost’s colonists await the launch of a cargo-laden U.S. resupply ship.

Stephen Bowen and Woody Hoburg will do a June 9 spacewalk to install one of two new roll-out solar arrays on the space station’s starboard-side truss structure.

The pair configured spacesuits and spacewalk gear inside the Quest airlock on Friday morning. In the afternoon, Hoburg checked his EMU with NASA Flight Engineer Frank Rubio.

To enhance Earth and space health, the crew continued microgravity studies. Bowen centrifuged blood samples and stored them in a laboratory freezer to study how spaceflight impacts cellular immunological capabilities.

The Harmony module’s space-facing port holds the SpaceX Dragon Freedom spaceship.

For the Cardiobreath astronaut health research, UAE astronaut Sultan Alneyadi pedaled while wearing sensors to measure his respiration and blood pressure. For a space biochemistry investigation, Rubio exchanged protein crystal samples in the Kibo laboratory module.

Friday’s human research study by Roscosmos Flight Engineers Dmitri Petelin and Andrey Fedyaev examined how microgravity affects digestion. Commander Sergey Prokopyev explored how electrons, ions, and neutral gases combine to form plasma crystals when electrically charged.

With two new roll-out solar panels in its unpressurized trunk, the SpaceX Dragon cargo vehicle will launch from Kennedy Space Center in Florida at 12:35 p.m. EDT on Saturday.

On Thursday, mission management polled the station and Dragon crews and reported all systems go for launch to the orbiting lab. However, weather forecasts indicated on Friday that launch pad conditions are 70% no-go with sporadic thunderstorms likely for Saturday and Sunday launch attempts.

Dragon’s automatic rendezvous and docking to Harmony’s space-facing port is slated for Monday at 5:36 a.m. Two days later, the Canadarm2 robotic arm will remove the roll-out solar panels from Dragon’s trunk and arrange them on the starboard truss pallet. After retrieving the solar panels, the two spacewalkers may install them.