Looking Homeward

Cassini is orbiting Saturn, taking stunning photographs of that planet's complex and beautiful system. But on Sunday, Saturn was between Cassini and the sun - and Cassini could aim its camera back at Earth. Here's the picture - a "pale blue dot" from the outer solar system. That's it, a little more than a third of the way down from the top, towards the right-hand side of the picture, the side with the rings. The inset is a blow-up - that "bulge" is the Moon.

How small. How far away - the Moon looks like it's part of us. How humbling.

The JPL site says:

Not since NASA's Voyager 1 spacecraft saw our home as a pale blue dot from beyond the orbit of Neptune has Earth been imaged in color from the outer solar system. Now, Cassini casts powerful eyes on our home planet, and captures Earth, a pale blue orb -- and a faint suggestion of our moon -- among the glories of the Saturn system.

Earth is captured here in a natural color portrait made possible by the passing of Saturn directly in front of the sun from Cassini's point of view. At the distance of Saturn's orbit, Earth is too narrowly separated from the sun for the spacecraft to safely point its cameras and other instruments toward its birthplace without protection from the sun's glare.

The Earth-and-moon system is visible as a bright blue point on the right side of the image above center. Here, Cassini is looking down on the Atlantic Ocean and the western coast of north Africa. The phase angle of Earth, seen from Cassini is about 30 degrees.

A magnified view of the image (see figure 1) taken through the clear filter (monochrome) shows the moon as a dim protrusion to the upper left of Earth. Seen from the outer solar system through Cassini's cameras, the entire expanse of direct human experience, so far, is nothing more than a few pixels across.

A few pixels ... holding all of us. We'd better learn to take care of it.