A robotic space probe nearly 900 million miles (1.5 billion km) from Earth turned its gaze away from Saturn and its entourage of moons to take a picture of its home planet, NASA said on Monday.
The resulting image shows Earth as a very small, blue-tinged dot - paler and tinier than in other photos - overshadowed by the giant Saturn's rings in foreground.
"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," Linda Spilker, Cassini spacecraft lead scientist at the Jet Propulsion Laboratory in Pasadena, California, said in a statement.
Cassini snapped the picture on Friday, the same day NASA's Mercury-orbiting MESSENGER probe imaged Earth as well. In that picture, Earth and the moon take up less than a pixel, but appear large because they are overexposed.
"That images of our planet have been acquired on a single day from two distant solar system outposts reminds us of this nation's stunning technical accomplishments in planetary exploration," MESSENGER lead scientist Sean Solomon, with Columbia University in New York, said in a statement.
NASA image shows a raw image of the Earth-Moon system as captured by the Cassini mission orbiting Saturn in the outer solar system. (AFP photo)
"The whole event underscores for me our 'coming of age' as planetary explorers," added astronomer Carolyn Porco, who oversees the Cassini imaging team at the Space Science Institute in Boulder, Colorado.
Usually, spacecraft in the far reaches of the solar system don't look back toward Earth to avoid damaging their instruments by direct sunlight. Last week, the sun was temporarily blocked relative to Cassini's line of sight, allowing the US space agency to take the picture.