Humans have lived on ISS for 25 years: here’s how they left their mark

November 2, 2025

— The International Space Station has, as of today (Nov. 2), served for every day of the last 25 years as a continuous home for a total of 162 people from 12 countries (290 people from 26 countries if including visitors). All of the residents made a mark by contributing to the station’s assembly or using the platform to conduct science.

They also left a more visual reminder that they were there.

The lasting record of the astronauts and cosmonauts’ part in the past 25 years of an uninterrupted human presense are colorful appliques, sometimes enhanced by their signatures. All of the expedition crews are represented by their emblems, as 4-inch (10.2-cm) decals added to the space station’s walls.

“I would say maybe some of the panels that have stickers of the station’s crews. So these panels would be the nice candidates to return maybe,” said current ISS resident, Expedition 73 flight engineer Kimiya Yui, in a pre-flight interview with collectSPACE about what components of the ISS would best represent the human story after its retirement and destruction.

The mission patch mosaics, which over the past quarter century have become part of the iconography of the space station, almost did not exist.

They were there

The first people to call ISS their home moved inside on Nov. 2, 2000. Back then, the space station was a lot simpler than it is today, with only three of its eventual 17 pressurized rooms in orbit.

The burgeoning complex that Expedition 1 crewmates William Shepherd, Yuri Gidzenko and Sergei Krikalev lived on for 136 days began as two Russian modules — the Zarya FGB (functional cargo block) and Zvezda service module — and the U.S.-provided “Unity” node. It was through the latter that the first visiting space shuttle crews came and went and, along the way, affixed their decals to a floor-to-ceiling-long panel.

Despite their visitors doing so, the Expedition 1 crew did not follow suit when it came to displaying their insignia.

“It just wasn’t something we gave much thought to,” Shepherd told collectSPACE, adding that he was fairly sure they didn’t even have a decal had they wanted to affix one.

The same was true for most of Expedition 2. By the time Jim Voss, Susan Helms and Yury Usachev arrived to take over for Expedition 1, seven decals were already on the “patch panel” in Unity and another four would be added before they realized what was missing.

“The way I remember it, we thought it would be a good idea for each [expedition] crew to leave their patch as a memento of their time on ISS. We asked a visiting crew to bring patches,” Voss wrote in an email. “We installed the ISS-1 and ISS-2 decals.”

Rather than mix the visiting and resident crews, Voss, Helms and Usachev chose a different area for the expedition stickers to be added. The decals were affixed to a salmon-colored beam above the hatchway that would eventually lead into Node 3 (“Tranquility”), once it arrived during Expedition 22 in 2010.

A photograph taken in August 2001, shows STS-105 commander Scott Horowitz applying the shuttle mission’s sticker to the panel, adjacent to the first two, newly-added expedition decals.

Decal details

As the expeditions began mounting up, the beam in Unity filled up. The original area had the decals for Expeditions 1 through 12 on its front and Expeditions 12 through 23* on its upper surface. The decals then continued onto a similar beam outside the hatchway leading from Unity into the Quest airlock, with Expeditions 24 through 33 on its front and Expeditions 34 through 44 and 45 to 52 on its upper surface.

(*Photos of the beam show that the Expedition 13 decal was applied twice after an addition to the crew resulted in a redesign of the patch and Expedition 18 was either removed at some point or never applied, but a space is left open between 17 and 19 to add it.)

The Expedition 53 crew placed their decal on a white panel behind the salmon beam in the threshold to the airlock. Expeditions 54 through 57 continued along that entrance into Quest (those insignia, though, are obscured when the hatch is open leading into visiting cargo spacecraft).

Expeditions 58 through 63 are represented along a salmon-colored beam above the hatch for Quest. Expedition 64 through the present have returned to the original beam, using the side below the first 12 crews.

Other decal collections were established elsewhere on the space station. Insignia for Russian Soyuz crews were added around the hatch and on a bright yellow panel in the Zvezda service module. Astronauts who performed spacewalks out of the U.S. side of the space station applied their mission decal and signed near their name on a panel inside the Quest airlock.

Stickers for visiting American, Japanese and European cargo vehicles were applied in the thresholds between their hatches and the station. European astronauts have also created a display of their insignia for their European Space Agency (ESA) science missions.

More recent crews arriving at the space station on U.S. commercial crew vehicles added their stickers and signatures inside the pressurized mating adapter linking their spacecraft to the ISS.

(The original “patch panel” with the shuttle visiting crew insignia was removed in 2009 as part of the modifications made to Unity to support adding Tranquility. It was replaced by a panel that arrived on the space station with decals for STS-88 through 128 already affixed. The tradition continued through the end of the shuttle program with the STS-135 crew emblem. The original panel is on display at the front of the station’s mission control room in Houston.)

Signing off

Given all of the places where the space station’s resident and visiting crews have placed their decals, there could be as many as 200 to 250 (if not more) mission patches decorating the ISS (excluding the stickers for science investigations and crew equipment).

A number of the displays have been enhanced with crew members’ autographs.

“We did do that,” said Helms in an interview with collectSPACE. “Did someone find our signatures?”

The Expedition 2 crew, along with the five astronauts on space shuttle Atlantis’ mission STS-104, were the first to sign the station’s surface. They did so, though, in an area where they thought no one would see, according to Helms.

“My recollection is we would not have signed something where our signatures would have been out there for people to see and be photographed. We probably signed something that was permanently covered up by the actual installation,” she said. “That’s my recollection. Of course, it has been almost 25 years.”

A seldom seen photo taken by someone on the joint crew documents what they wrote, but provides no obvious hints at where it is, other than in or near the station’s exit.

“The first EVA was conducted from the joint airlock ‘Quest’ on July 20, 2001, by the ISS 7A crew,” read the inscription. Below that are an STS-104 decal and an embroidered Expedition 2 patch with the autographs of Steve Lindsey, Charles Hobaugh, Jim Reilly, Janet Kavandi, Mike Gernhardt, Voss, Helms and Usachev.

Like the decals, although not as complete a record, the signatures subsequently left by the crews are a visual reminder that the space station is more than a collection of hardware and science results. For now a quarter of a century, it has been a continuous chapter in human history.