The image below was taken by Apollo 17 Astronaut Harrison Schmitt, one of the last men to walk on the moon. A tight triangular formation of blue lights is clearly visible on the right side of the image above the sharply upsloping rise. This is not a cluster of stars and, given the fact that it is the only thing visible in an otherwise black sky, it must have been very bright. The bright surface of the moon has washed out any starlight.
This is not a natural object. Is it therefore an alien spacecraft? That we cannot say, but it is certainly something unknown. It has not been referenced in any way by NASA. Our image has been slightly contrast enhanced using Adobe Photoshop in order to make the triangle easier to seek. It is visible in the original NASA photo.