Space and Physics
PUBLISHED
What color do you think of when you picture an astronaut’s clothing? Is it the white of the extravehicular activity spacesuit? Is it the blue of their jackets and earthbound uniform? Or is it the orange of the launch suits, as seen in Artemis II and many shuttle launches? It turns out that astronauts can be a colorful bunch – and the orange in particular has a very important reason to exist.
Firstly, it isn’t just any old orange. It’s "international orange," and in the aerospace industry, it has a very specific hue: #FF4F00 if you go by hex triplet or (255, 79, 0) by sRGB. The Golden Gate Bridge in San Francisco is painted in a slightly different shade of international orange, and the reason is the same: visibility.
If you want to find something – especially at sea, where astronauts might end up after splashdown – you want a color that really stands out against the blue of the water. Orange will do that job.
Historically, orange hasn’t always been the standard, however. Spacesuits are designed to protect the astronauts in case of sudden cabin depressurization. The Mercury program spacesuits were metallic in color and made of aluminum-coated nylon for thermal control purposes. The style is certainly responsible for a certain aesthetic of 1960s sci-fi movies.
With Gemini, the color shifted to white as the material insulation changed. This continued with the Apollo suit and, subsequently, with the suits used on Skylab – the first US space station – by then featuring fashionable blue and red accent colors that matched the NASA logo. The space shuttle era brought new colors, with a mustard number that was certainly an interesting choice.
The switch to orange came following the Challenger disaster, when in 1986 the space shuttle Challenger exploded 73 seconds into its flight, killing all seven crew members, including schoolteacher Christa McAuliffe. From then on, NASA has used the orange launch suit, as it would be highly visible in search and rescue operations.
Following the retirement of the space shuttle, and prior to the advent of the Space Launch System, NASA’s access to low Earth orbit has been either via Russia or through private companies. SpaceX launch suits are white, while the beleaguered Boeing Starliner's ones are blue.
For Artemis, NASA has carried on using international orange. The Orion spacecraft has been designed with multiple abort systems that could take astronauts away from the rocket if something unexpected happens. Different modes would send Orion to splash down in the Atlantic relatively close, or on the east Atlantic, either near Ireland, Britain, Spain, or Morocco. A third mode would send just Orion into a shallow orbit to re-enter in the Pacific. All these scenarios involve the sea. Hence the orange suit.
The official successful re-entry plan involves the sea as well. For Artemis II, Orion is planned to splash down in the Pacific Ocean off the coast of San Diego, California, on Friday, April 10, 2026, at around 8:07 pm EDT.
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