What did the March 18, 2026 NASA spacewalk accomplish?

Astronauts Jessica Meir and Chris Williams exited the International Space Station on March 18, 2026 at 8:52 AM EDT for a 6.5-hour extravehicular activity (EVA). Their primary task was to install the bracket mounting structure for the 7th iROSA — ISS Roll-Out Solar Array — on the port truss of the station. The bracket installation is the critical first step before the solar array itself is deployed. This was NASA's first spacewalk in approximately 10 months, following a period when EVA activities were paused for equipment reviews and crew scheduling.

What is an iROSA and how does it work?

An iROSA — ISS Roll-Out Solar Array — is a new generation of compact solar power system developed by Boeing for the International Space Station. Unlike traditional rigid solar panels, iROSAs are stored rolled up like a carpet and deploy by unrolling outward using carbon composite boom structures without requiring any motors. Once triggered, the array self-deploys in approximately 6 minutes, unrolling to its full 19 by 6 meter size. iROSAs are installed on top of the existing ISS solar arrays to supplement their aging panels, which have degraded in efficiency after over 25 years of operation in space radiation and thermal cycling environments.

Why is NASA installing new solar arrays on a space station that will be deorbited?

NASA is upgrading the ISS solar power systems for two interconnected reasons. First, the additional power from the 8 iROSAs enables full operation of all station systems through the ISS's planned operational life to 2030, as the original solar arrays have degraded to approximately 60% of their original output after 25 years. Second, and crucially, the upgraded power systems will support the ISS's safe controlled deorbit — planned for 2030. The deorbit requires the station's propulsion and attitude control systems to execute precise burns over several months, all of which require reliable electrical power. Without the iROSAs, power margin for deorbit operations would be insufficient.

When is the ISS scheduled to be deorbited and what happens to it?

NASA plans to deorbit the International Space Station in January 2030 with a controlled atmospheric reentry. The station will not be destroyed in orbit — instead, its orbit will be gradually lowered over several months using onboard propulsion, then a final large deorbit burn will direct it into the atmosphere over the South Pacific Ocean. Most of the station's 420-metric-ton mass will burn up during reentry. Larger structural components that survive are targeted to splash down in the uninhabited Point Nemo ocean region — the most remote location on Earth, already used for deorbiting spacecraft. A private deorbit vehicle is being developed by SpaceX under a NASA contract to assist with the final deorbit burn.

How does the ISS solar array upgrade compare to recent Chinese space station work?

The same week as NASA's March 18 EVA, China's Tiangong space station astronaut Zhang Lu completed a 7-hour spacewalk — his sixth EVA — tying the Chinese spacewalk frequency record. China's Tiangong station is newer and was built with modern solar array technology from the start, so it does not require retrofit upgrades like the ISS iROSA program. However, Tiangong's smaller scale means its power systems are less complex than the ISS. The coincidence of both stations conducting major EVA activities in the same week reflects the ongoing dual-track human spaceflight programs being pursued by the US-led alliance and China independently.

/// Space Science 2026

NASA Spacewalk Upgrades ISS Solar Arrays for Future Deorbit

Published: March 19, 2026

Astronauts Jessica Meir and Chris Williams conducted a 6.5-hour spacewalk on March 18, 2026 to install the bracket for the 7th of 8 new roll-out solar arrays on the ISS, supporting its eventual controlled deorbit in 2030.

EVA Duration

6.5h

iROSA No.

7 / 8

Self-Deploy

6 min

ISS Deorbit

2030

SCROLL DOWN

02 / KEY FACTS

What Happened on March 18, 2026

Astronauts Jessica Meir and Chris Williams executed NASA's first spacewalk in approximately 10 months — installing the bracket structure for the 7th of 8 new roll-out solar arrays to upgrade ISS power systems and prepare for the station's controlled 2030 deorbit.

Photo: NASA — Astronauts Meir and Williams spacewalk outside ISS

EVA Start

8:52 AM EDT

March 18, 2026

EVA Duration

6.5h

Extravehicular activity

iROSA Installed

#7 / 8

Bracket on port truss

Self-Deploy Time

~6 min

No motor required

03 / iROSA TECHNOLOGY

How Does the iROSA Work?

The ISS Roll-Out Solar Array (iROSA) is an elegant engineering solution — a compact, self-deploying solar array requiring no motor, designed to supplement the ISS's aging original solar panels.

Motorless Roll-Out Design

The iROSA is stored rolled up like a carpet and self-deploys by unrolling outward using carbon composite boom structures — no motor required at all. The self-deployment process completes in approximately 6 minutes.

[1] NASA Blog — March 18, 2026

Overlay on Aging Arrays

The iROSA panels are installed on top of the ISS's original solar arrays, which have degraded to approximately 60% of their original output after more than 25 years of exposure to space radiation and continuous thermal cycling.

Size & Power Output

Each iROSA measures 19 by 6 meters when fully deployed. All 8 arrays together add substantial electrical power, ensuring the ISS operates at full capacity through its remaining operational period and during the controlled 2030 deorbit.

[1] Space.com — EVA Report

Supporting the 2030 Deorbit

The upgraded power systems will supply the ISS's propulsion and attitude control systems during the multi-month deorbit process. Without the iROSAs, the power margin for deorbit operations would be insufficient.

04 / ASTRONAUTS & MISSION

Jessica Meir & Chris Williams: The EVA Team

Astronauts Jessica Meir and Chris Williams of Expedition 72 crew conducted the EVA on March 18, 2026 — NASA's first spacewalk in nearly 10 months. Their mission focused on installing the bracket assembly for the 7th iROSA on the port S6 truss segment.

Jessica Meir

NASA Astronaut

Experienced astronaut with multiple previous EVAs on the ISS. Known for the first all-female spacewalk in 2019 alongside Christina Koch.

Chris Williams

NASA Astronaut

Expedition 72 crew member, conducting this EVA as part of his long-duration mission aboard the International Space Station.

Photo: NASA — Astronaut spacewalking alongside ISS solar arrays in orbit

05 / PROGRAM TIMELINE

The iROSA Upgrade Roadmap: 2023 to 2026

The iROSA upgrade program began in 2023 and is expected to complete in 2026 with all eight arrays fully installed, ensuring the ISS has sufficient power for all remaining operations through deorbit.

May 2023

iROSAs 1 & 2 Installed

NASA conducts the first spacewalks of the iROSA upgrade program, installing the first two roll-out solar arrays on the ISS.

June 2023

iROSAs 3 & 4 Installed

Expedition 69 crew continues the upgrade program, installing two more iROSA panels, bringing the total to four.

June 2024

iROSAs 5 & 6 Installed

After a pause in EVA operations, Expedition 71 crew installs iROSAs 5 and 6, adding substantial additional electrical capacity to the station.

March 18, 2026LATEST EVENT

EVA — iROSA 7 Bracket Install

Astronauts Jessica Meir and Chris Williams exit the ISS at 8:52 AM EDT, conducting a 6.5-hour EVA to install the bracket structure for iROSA 7 on the port truss. This is NASA's first spacewalk in approximately 10 months.

Planned 2026

iROSA 8 — Program Complete

A final EVA will install the eighth and last iROSA panel, completing the entire ISS solar power upgrade program and ensuring the station has sufficient power for all remaining operations through 2030.

06 / ISS DEORBIT 2030

Why Does ISS Need Power Upgrades Before Deorbit?

The ISS is planned for a controlled deorbit in January 2030. This process requires reliable electrical power to operate propulsion and attitude control systems over several months. The iROSA program ensures the ISS has sufficient power margin for all these final operations.

Photo: NASA — ISS solar array installation

Deorbit Plan

NASA plans to deorbit the ISS in January 2030 with a controlled atmospheric reentry over the South Pacific Ocean.

Power Requirement

Propulsion and attitude control systems need reliable power during the multi-month deorbit process. iROSAs ensure sufficient power margin.

SpaceX Deorbit Vehicle

SpaceX is developing a private deorbit vehicle under a NASA contract to assist with the final deorbit burn in 2030.

07 / GLOBAL CONTEXT

A Week of Parallel EVAs: NASA & China

The same week as NASA's March 18 EVA, China's Tiangong space station also conducted a 7-hour EVA — a notable coincidence reflecting the parallel human spaceflight race between the two space powers.

NASA / ISS

6.5-hour EVA — Meir & Williams, iROSA 7 bracket install

HIGHLIGHTED EVENT

China / Tiangong

7-hour EVA — Zhang Lu, 6th EVA (ties Chinese EVA record)

▸ If you are interested in space tourism, ISS will be decommissioned by 2030 — after which commercial stations (Axiom, Orbital Reef) may offer orbital tourism seats starting at $55M per trip.

Other space missions worth following include the Vera Rubin Observatory and the NASA ESCAPADE Mars mission.

08 / REFERENCES