On 19 July 2013, Nasa’s Cassini spacecraft captured this rare image of Saturn’s rings, our planet Earth and its Moon all in the same frame. This image is only one footprint in a mosaic of 33 footprints covering the entire Saturn ring system (including Saturn itself). At each footprint, images were taken in different spectral filters for a total of 323 images. This is the only wide-angle footprint that has the Earth-Moon system in it.
The dark side of Saturn, its bright limb, the main rings, the F ring, and the G and E rings are clearly seen; the limb of Saturn and the F ring are overexposed. The “breaks” in the brightness of Saturn’s limb are due to the shadows of the rings on the globe of Saturn, preventing sunlight from shining through the atmosphere in those regions. The E and G rings have been brightened for better visibility.
Earth, which is 1,44 billion kilometres away in this image, appears as a blue dot at centre right; the Moon can be seen as a fainter protrusion off its right side. An arrow indicates their location in this annotated version.
This is only the third time ever that Earth has been imaged from the outer solar system.
Image credit: Nasa/JPL-Caltech/Space Science Institute