This NASA simulation of the mosaic of Saturn's rings shows how big the image of Earth will be. I think that's you in the red hat. 


NASA’s Cassini spacecraft is going to take our picture Friday afternoon and the space agency is encouraging us to go outside and wave at the camera, or at least smile, between 2:27 p.m. and 2:42 p.m. Arizona time.

Don’t bother combing your hair or dressing up for the occasion. You won’t be visible in this photograph taken from a spacecraft that is orbiting Saturn nearly 900 million miles away.

Consider how small we are as a planet. Saturn, with an overall volume that is 764 times greater than Earth’s, appears in the sky as a point of light equivalent to a bright star. Earth, from the vantage point of a spacecraft orbiting Saturn, will be no more than a single pixel in the panoramic portrait of Saturn and its rings being taken by the Cassini team.

But if you’d like to play along, look in the direction of the eastern horizon, where Saturn will be invisible in the daytime sky, wave and smile for 15 minutes.

Then go explain yourself to your neighbors.

There is a scientific purpose to all of this. The Cassini mission explains:

“The main science goal for the mosaic we are making of the Saturn system is to look at the more diffuse rings that encircle Saturn and check for change over time. A previous mosaic of the Saturn system Cassini made in 2006 revealed that the dusty E ring, which is fed by the water-ice plume of the moon Enceladus, had unexpectedly large variations in brightness and color around its orbit. We'll want to see how that looks seven Earth years and a Saturnian season later, giving us clues to the forces at work in the Saturn system. We'll do this analysis by collecting data from our visual and infrared mapping spectrometer, composite infrared mapping spectrometer and ultraviolet imaging spectrograph in addition to the imaging cameras.”

NASA wants you to send a photo of yourself waving at Saturn. Details are here.