Sun analemma. Artwork of the analemma, the figure of eight shape made by plotting the position of the Sun at the same time of day during the year. The analemma is caused because the axis of the Earth's rotation is not perfectly perpendicular to the p...

Anatomy of a black hole showing the accretion disc, jets, ergosphere, inner and outer event horizons, static limit and singularity....

Illustration of an exaggerated Earth seen from the surface of the Moon. The Sun is behind us and below the horizon, so the Earth is seen in gibbous phase, its blue light providing the illumination for the scene. No stars are seen here - they are wash...