The Cassini spacecraft has sent back rare photos of Earth as seen from its orbit around Saturn.
In 1990, Voyager 1 reached the edge of the solar system and snapped a picture of the Earth from 6 billion kilometres away. That photo — called "The Pale Blue Dot" — was the farthest point from which we'd ever seen our own planet.
NASA's Cassini — surveying Saturn and its satellites since 2004 — isn't quite so far away, but has offered us another rare glimpse of our planet as seen far from home: approximately 1.44 billion kilometres away.
Snapped on 19 July as part of a wide-angle mosaic of Saturn's rings, it shows Earth peeking out from behind, just a shining blue dot in the depths of space. Usually, the Earth is obscured in photos taken by spacecraft by the light of the sun; this photo was possible because the sun was tucked away behind Saturn's bulk.
"We can't see individual continents or people in this portrait of Earth, but this pale blue dot is a succinct summary of who we were on 19 July," said Linda Spilker, Cassini project scientist. "Cassini's picture reminds us how tiny our home planet is in the vastness of space, and also testifies to the ingenuity of the citizens of this tiny planet to send a robotic spacecraft so far away from home to study Saturn and take a look-back photo of Earth."
Also seen in the photo is the dark side of Saturn, its main rings, and the F, G and E rings. The images were taken with red, blue and green spectral filters, combined to provide the image in colour.
Cassini managed to capture a closer view, too — showing not just the Earth, but the moon in orbit around it. While capturing the wide-angle mosaic, Cassini also snapped some narrow-angle images to try to get a shot of the Earth. The Earth appears in blue, the smaller moon in white off to the right.
These photos mark only the third time the Earth has been photographed from the outer solar system. The first was the aforementioned "Pale Blue Dot". Then, in 2006, Cassini captured "In Saturn's Shadow: The Pale Blue Dot", where Earth appears between Saturn's rings to the left of the planet.