Smile! Cassini wants to take your picture

Mara D. Bellaby | Florida Today

Show Caption Hide Caption Sights, sounds from aboard Cassini spacecraft This video highlights sights and sounds from the journey of NASA's Cassini spacecraft. Cassini launched 15 years ago and has been exploring the Saturn system since 2004. NASA video

The Cassini spacecraft launched on Oct. 15%2C 1997%2C entered orbit around Saturn on July 1%2C 2004

16 European countries and the United States have participated in its mission

Cassini%27s mission is planned to end in 2017 when it will fall into Saturn%27s atmosphere

CAPE CANAVERAL, Fla. — NASA wants you to wave at Saturn on Friday.

The space agency plans to take an interplanetary photo and wants you looking attentive when its photographer snaps the image from 898 million miles away.

Between 5:27 and 5:42 p.m. ET, NASA plans to train the Cassini spacecraft's highest-resolution camera toward Earth. Cassini, which launched from Cape Canaveral in 1997, is exploring Saturn.

Earth will appear as a small, pale blue dot between the rings of Saturn — so don't expect to see yourself. But the space agency still wants Earthlings to have some fun with the photo shoot since deep space photos of home are rare. This is only NASA's third.

"While Earth will be only about a pixel in size from Cassini's vantage point, ... 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 in Pasadena, Calif, said in a statement.

The principal scientific goal of the effort is to study Saturn's rings since the sun will be backlighting the planet. Getting Earth in the mosaic is a nice bonus.

NASA has a long history of providing space-based images of Earth, such as the 1968 "Earthrise" photograph that the Apollo 8 moon mission crew took from about 240,000 miles away.

But taking photos of Earth from the outer solar system is more challenging because the sun can blind the spacecraft's cameras. The July 19 photo opp is possible because Cassini will be in Saturn's shadow.

The only other deep space home portraits: the 1990 "Pale Blue Dot" image taken by Voyager 1 from 4 billion miles away, and another that Cassini shot in 2006 from 926 million miles away.

If you miss Cassini's glamour shot, don't fret. You can be outside at 7:49 a.m., 8:38 a.m. or 9:41 a.m. ET Saturday to be part of images that NASA's Messenger spacecraft will be taking as it orbits Mercury.