Image: The colors of sunset over the ISS
ESA astronaut Samantha Cristoforetti took these images from the International Space Station during her six-month mission. The Progress cargo ship and Soyuz crew spacecraft reflect sunlight as our star sets behind Earth.
Traveling at 28 800 km/h, astronauts can enjoy sunset and sunrise 16 times a day as they circle our planet in the Space Station.
Samantha commented on the pictures: "Before the orbital night embraces our outpost in space this cold metallic light shines on the Space Station" and "Have I mentioned how I love it when the Space Station is cuddled by this orange embrace?"
The colours appear as sunlight slices through the atmosphere. Light with shorter wavelengths is scattered by oxygen in the air first and appears blue. If sunlight hits the atmosphere at a low angle, it travels further through the air and more blue light is filtered out, creating the redder hue.
A sunset happens quickly in orbit – these two images were taken just two minutes apart before the Sun disappeared, returning just 45 minutes later.