Social media users have claimed that because stars are not routinely visible in photographs taken from spacecraft, space itself is a hoax.
One clip that circulated online showed images taken from the Artemis I Orion shuttle with no stars visible. Later imagery showed a sky full of stars captured from Earth (here).
Another example of the claim shared online can be seen (here).
Stars not being visible in imagery taken from space is not proof that the universe does not exist, and the claim has previously provided fodder for Apollo 11 lunar landing conspiracy theories, addressed by the Royal Museums Greenwich (here).
“Essentially, the reason we can’t see the stars from cameras placed on spacecraft is because in order to see the spacecraft itself (or the Moon or Earth in the case of the Artemis mission) it has to be daytime,” Dr Becky Smethurst, astrophysicist at the University of Oxford told Reuters.
“The Sun is shining on the spacecraft, or Moon, and the camera is adapted to that brightness and can’t pick up the faint light from the stars in the background at the same time,” she added.
It may appear as if imagery taken from space is captured at nighttime due to the background being black rather than blue. However, the daytime sky on Earth is only blue due to “scattering of light in the Earth’s atmosphere,” Smethurst said. “Above the atmosphere, the daytime sky appears black.”
Astrophotographer Andrew McCarthy told Reuters that when taking a photograph of something in space, just as on Earth, the exposure is set for the subject in question. In the case of the Artemis I mission, the settings would be adjusted to focus on the Earth, Moon and the spacecraft itself.
“One thing all these things have in common: They’re in direct sunlight. Therefore, they’re quite bright! The relatively fainter stars are certainly present, but without changing the exposure (which would of course completely overexpose the objects in direct sunlight) they will remain invisible in the photographs,” McCarthy said.
This can be tested at home, McCarthy told Reuters, by trying to take a photo of a full moon and stars at the same time.
“Cameras have limited dynamic range, so unlike our eyes, they can’t see the stars and the moon at the same time. Most Earthly photos of stars are taken without also having something in direct sunlight in them, so the exposure difference isn’t always going to be a challenge,” McCarthy said.
“Taking an image of both the sunlit Orion spacecraft and the stars would be like trying to take an image of a smartphone torch next to a stadium floodlight; one is much brighter than the other and glares out the fainter light,” Smethurst told Reuters.
Missing context. A camera taking photographs from a spacecraft when the sun’s light is shining on objects such as the spacecraft itself, or the Earth and Moon, means that it would be too dark for a camera to capture the faint light from stars in the background.
This article was produced by the Reuters Fact Check team. Read more about our fact-checking work here.
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