The OSIRIS-REx spacecraft has been orbiting the wee asteroid Bennu for nearly a year now. It’s been mapping the asteroid’s surface, taking a measure of its gravity to get its mass, proven it’s a rubble pile, has seen it bizarrely spitting rocks into space, and has been scoping out a place to briefly touch the surface long enough to collect some samples to eventually return to Earth. The mission so far has been a tremendous success.
As the spacecraft orbits, it takes lots of images from its various cameras, including the navigation camera, usually just called Navcam. This is a 5 megapixel camera with a very wide 44 x 32 degree field of view — on Earth, this would be a field of view over 80 times wider than the full Moon in the sky! It takes such wide-angle shots because those are used for navigation; it can see down to relatively faint stars and use those to figure out where it is and what its orientation is.
On 19 January, 2019, the Navcam took a long exposure of the sky — five seconds — when Bennu was in the field of view. The image is pretty amazing:
A very ...