In the next few weeks, astronauts will come out of the International Space Station’s air-blocking module to conduct a series of three spacewalks aimed at upgrading the station’s aging electrical system.
The ISS uses large solar panels to collect the sun’s energy and convert it into usable electricity for life support, temperature control, communication with Earth, and for its propulsion systems to enable the station to avoid space debris.
The old ISS power system, which consisted of eight solar arrays that spread out like wings from the exterior of the station, has so far been able to meet the station’s power needs, producing an average of 84 to 120 kilowatts of electricity. However, some of these arrays are more than 20 years old and were originally designed for a 15-year lifespan, so they are already showing signs of age.
This doesn’t mean that older arrays will suddenly lose power or stop working, but they are becoming less efficient over time. And with a large number of increasingly complex scientific experiments being conducted on the space station, the power requirements are on the rise.
In order to keep up with the power demands of the space station, the ISS has been constantly upgrading its power systems, including previously replacing batteries. Now, new solar arrays need to be added, which is the main purpose of the upcoming spacewalk.
The upgrades to the electrical system include the addition of six new arrays that will be placed in front of the old ones. The new arrays are 60 feet (about 1,830 centimeters) long and 20 feet (about 610 centimeters) wide and are called “ISS Roll-Out Solar Arrays,” or iROSA, and are smaller than the old arrays, which are 112 feet (about 3,416 centimeters) long and 39 feet (about 1,189.5 centimeters) wide. 1189.5 cm) wide. However, advances in solar panel technology mean that the new array can produce about the same amount of power as the original array.
However, adding new arrays is not a simple process. Before the iROSA arrays can be added, support structures, called mod kits, need to be installed on the exterior of the space station. the process is a two-step process, with scaffolding installed first, followed by the arrays. Currently, two new iROSA arrays have been installed on the International Space Station. The scaffolding for the other two is ready, and the scaffolding for the final two will be installed soon, starting with the upcoming spacewalk on Nov. 15. This will be the first-ever spacewalk by NASA astronauts Josh Cassada and Frank Rubio.
Two subsequent spacewalks are tentatively scheduled for Nov. 28 and Dec. 1, and then two more arrays will be installed on top of the existing scaffolding, with the goal of having all six arrays installed and operational by the middle of next year.
The new solar arrays will arrive folded up for the SpaceX CRS-26 resupply mission, which launches Nov. 18. The arrays will then be installed, integrated into the power system, and deployed. To integrate with the power system, spacewalkers will need to install Y-cables to connect the old and new arrays to the power system.
NASA says these new arrays are being tested for possible use in future missions, such as the Artemis Moon program, as well as to help keep the space station operational. As for the space station, its exact future remains unclear. Although NASA announced late last year that it intends to continue operating the International Space Station until 2030.
