Photos of Earth and the Moon taken by a spacecraft orbiting Saturn nearly a billion miles away have been released by Nasa.
The pictures were taken by the Cassini spacecraft and between Saturn’s rings the earth appears as a pale blue dot, while the moon is a stark white dot.
It was the first time Cassini’s highest-resolution camera captured Earth and its moon as two distinct objects.
The photos also marked the first time people on Earth had advance notice their planet’s portrait was being taken from interplanetary distances.
Nasa invited the public to celebrate by finding Saturn in their part of the sky, waving at the ringed planet and sharing pictures online.
More than 20,000 people around the world participated when the pictures were taken on July 19.
Carolyn Porco, from the Space Science Institute in Boulder, Colorado, who leads Cassini’s camera team, described the event as an ‘interplanetary cosmic photo session’.
She added: ‘It thrills me no end that people all over the world took a break from their normal activities to go outside and celebrate the interplanetary salute between robot and maker that these images represent.’
Linda Spilker, Cassini project scientist at Nasa’s Jet Propulsion Laboratory in Pasadena, California, added: ‘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 July 19.
‘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.’
A wide-angle image from Cassini will form part of a larger mosaic – or multi-image portrait – that imaging scientists are putting together of the entire Saturn system.
Pictures of Earth from the outer solar system are rare because from that distance, earth appears very close to our sun.
A camera’s sensitive detectors can be damaged by looking directly at the sun, just as human beings can damage their retina by doing the same.
Cassini was able to take this image because the sun had temporarily moved behind Saturn from the spacecraft’s point of view and most of the light was blocked.