Blog

Can Astronauts See
Stars In Space?

11 September 2015

The International Space Station as seen from space.NASA
The International Space Station as seen from space.

On the face of it, this might seem like a silly question. Of course we can see stars in space. We see stars more clearly from space than we do from Earth, which is why space telescopes are so useful. And yet, this question comes up again and again. Not just from moon landing skeptics and fringe science promoters, but from everyday folks who are sure they learned somewhere that stars can’t be seen in space.

When overexposed, the Moon seems to glow brilliantly.Bob King/Sky and Telescope
When overexposed, the Moon seems to glow brilliantly.

The origin of this misconception is usually traced back to an interview with the crew of Apollo 11, where (it is claimed) Neil Armstrong said he couldn’t see stars in space. What the crew were actually discussing at the time was the inability to see stars on the daylight side of the Moon, which is not surprising given how bright the lunar surface can be relative to the airless black of space. Even in space the stars aren’t overly bright, and our eyes can lose dark adaption pretty quickly.

An image from the ISS of stars and glowing layers of Earth's atmosphere.NASA
An image from the ISS of stars and glowing layers of Earth’s atmosphere.

But what about all those photos of objects in space, such as the one of the international space station seen above? There’s no stars to be seen in the image. It’s actually quite common to see images of planets and other objects against a starless black background. Doesn’t that support the idea of a starless sky in space? No, since it’s no surprise that an image focused on a bright object like a planet or moon won’t have a long enough exposure to see stars clearly. There are plenty of images from space that do show stars, as well as other faint phenomena such as the green airglow of our atmosphere.

What this misconception really shows is how easily a misconception can get locked into our heads. We can all fall prey to the trap of holding misconceptions without really thinking about them. That’s part of the reason why we focus on published and verifiable evidence in science.

Which is why this isn’t such a silly question after all.