Earth photographed by Nasa Saturn probe "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. "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 do not look back towards 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.