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Comment by StavrosK | Hacker News Reader

Isn't Cassini near Saturn? How is it going to image the Earth? Why are we waving?

>How is it going to image the Earth?

The sun is being blocked by saturn itself, so the earth will be visible to the camera. The real purpose is to image the rings. Actual info is here: http://saturn.jpl.nasa.gov/news/waveatsaturn/

> Why are we waving?

To ensure NASA's continued funding/for a bit of innocent amusement. Take your pick.

Right, so it's going to be far from the street-level imaging Google does, as I suspected.

Earth will be a few pixels at best. The pale blue dot photo has basically a single pixel of Earth, though Voyager was farther away than Cassini at the time (past the orbit of Saturn) and its cameras weren't as good.

Casini has a camera that's on the order of one megapixel in black and white. I'd be surprised if earth is more than a few pixels above the noise.

I think the idea is to recreate something like the famous Pale Blue Dot [1] image taken by Voyager 1. Here's a thought from Carl Sagan about that:

From this distant vantage point, the Earth might not seem of any particular interest. But for us, it's different. Consider again that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives.

[1] http://en.wikipedia.org/wiki/Pale_Blue_Dot

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