The ISS is getting its final pair of new solar arrays today
Key takeaways
- A Falcon 9 is scheduled to launch the CRS-35 Cargo Dragon at 6:33am EDT today with about 6,300 pounds of cargo.
- The trunk carries the final pair of ISS Roll-Out Solar Arrays, plus a clamshell for the Canadarm2 joint removed in a 30 June spacewalk.
- Docking is planned for about 11am EDT on 15 October at Harmony's zenith port, and Dragon stays about a month.
6:33am EDT, pre-sunrise, from Cape Canaveral. That is the scheduled liftoff time for CRS-35, SpaceX's 35th resupply mission to the International Space Station under NASA's Commercial Resupply Services contract. Tucked in the unpressurised trunk are the final two ISS Roll-Out Solar Arrays.
The Falcon 9 booster, B1096, is flying for the eighth time. Cargo Dragon C211 is on its fourth flight. Check the live coverage for whether it has gone, as launch times can slip.
What the new arrays do
The roll-out arrays, known as iROSAs, launch rolled up and unfurl once installed, adding power on top of the station's original arrays. Spaceflight Now says this pair will augment the station's power generation, but the coverage gives no figure for the gain and no date for the spacewalks that will fit them. Wikipedia has a fuller explanation of the design.
A broken arm joint comes home
Also in the trunk is a clamshell apparatus meant to house the failed Canadarm2 joint, which was removed in a spacewalk on 30 June. The coverage does not say when the joint will return to Earth or whether it will be repaired.
The rest of the manifest is less glamorous but matters more to daily life to daily life on board. NASA's Bill Spetch lists a dose pump for the toilet, pre-treat quality sensors and a robotic maintenance tool for external replacement units.
The science on board
The research cargo covers manufacturing artificial retinas, how microgravity affects the growth of 3D heart tissue models, glass formation using non-traditional elements, and links between inflammation and neurodegenerative disease. Our recent piece on Crew-12's 237 days in orbit shows why station science depends on exactly these slow, steady deliveries.
What to watch
Docking is planned for about 11am EDT on 15 October at the zenith port of the Harmony module. That port was vacated when Crew Dragon Freedom returned the four-person Crew-12 with a splashdown on 8 October. Dragon then stays for about a month.
The next date to circle is the first spacewalk to install the arrays. For a station that keeps ageing, new power is what keeps the lights on, and it is worth following alongside the next big launch on the calendar, MMX heading for Phobos on 19 October.
