NASA Cassini Probe to Photograph Earth from a Billion Miles Away

As NASA's Cassini spacecraft makes an orbit around Saturn next month, it will snap a special picture: an image of Earth from about one billion miles away.

The great distance will mean that Earth will only occupy about a pixel of the giant mosaic image of Saturn and its ring system.

This is not the first time an image of Earth has been taken from as far away as Saturn. Cassini mosaics from the ringed planet in 2006 and 2012 featured a spec of Earth. But the photo taken July 19 will be the first to capture the Saturn system with Earth in natural color, as human eyes would see it.

Another first will be Cassini photographing Earth with its highest resolution camera. Because of the position of the satellite, which will be facing the far side of Saturn as it eclipses the Sun, Cassini will be able to point its camera in the direction of the Sun where the Earth will be without damaging the spacecraft's instruments.

"Ever since we caught sight of the Earth among the rings of Saturn in September 2006 in a mosaic that has become one of Cassini's most beloved images, I have wanted to do it all over again, only better," Carolyn Porco, the Cassini imaging team lead at the Space Science Institute, said in a statement. "This time, I wanted to turn the entire event into an opportunity for everyone around the globe to savor the uniqueness of our planet and the preciousness of the life on it."

The novelty of the interplanetary photo-op is not lost on Porco.

"People can enjoy the fact that we have a robot out there, a billion miles away, taking our picture. How cool is that?" she said to BBC News.

"People can celebrate it and join in. This will be like an interplanetary cosmic photo session."

As Cassini captures the mosaic, images of Earth will be acquired between 17:27 and 17:42 EDT on 19 July. At the time of the photo, North America and part of the Atlantic Ocean will be in sunlight.

To that end, the space agency is asking people on Earth to wave at Saturn from home.

"While Earth will be only about a pixel in size from Cassini's vantage point 898 million (1.44 billion kilometers) away, the team is looking forward to giving the world a chance to see what their home looks like from Saturn," Linda Spilker, Cassini project scientist at NASA's Jet Propulsion Laboratory, said in a statement. "We hope you'll join us in waving at Saturn from Earth, so we can commemorate this special opportunity."