Cassini Sees Earth and Moon Through Saturn’s Rings

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NASA/JPL-Caltech/Space Science Institute

NASA’s Cassini mission sure has a knack for putting stuff into perspective — and this most recent view from Saturn orbit is no different. That dot in the center of the image isn’t a dud pixel in Cassini’s camera CCD. That’s us. All of us. Everyone.

To quote Carl Sagan:

“Look again at 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…”

Sagan wrote that passage in his book “Pale Blue Dot: A Vision of the Human Future in Space” when reflecting on the famous “Pale Blue Dot” image that was beamed back to Earth by NASA’s Voyager 1 spacecraft in 1990. That’s when the mission returned a profound view of our planet from a distance of 3.7 billion miles (or 40.5AU) as it was traveling through the solar system’s hinterlands, on its way to interstellar space. Since then, there’s been many versions of pale blue dots snapped by the armada of robotic missions around the solar system and Cassini has looked back at us on several occasions from its orbital perch.

Now, just before Cassini begins the final leg of its Saturnian odyssey, it has again spied Earth through a gap between the gas giant’s A ring (top) and F ring (bottom). In a cropped and enhanced version, our moon is even visible! The image is composed of many observations captured on April 12, stitched together as a mosaic when Saturn was 870 million miles (roughly 9.4AU) from Earth.

On April 20 (Friday), Cassini will make its final flyby of Titan, Saturn’s largest moon, using its gravity to fling itself through Saturn’s ring plane (on April 26) between the innermost ring and the planet’s cloudy upper atmosphere, revealing a view that we’ve never before seen. For 22 orbits, Cassini will dive into this uncharted region, possibly revealing new things about Saturn’s evolution, what material its rings contain and incredibly intimate views of its atmosphere.

This daring maneuver will signal the beginning of the end for this historic mission, however. On Sept. 15, Cassini will be intentionally steered into Saturn’s atmosphere to burn up as a human-made meteor. It is low in fuel, so NASA wants to avoid the spacecraft from crashing into and contaminating one of Saturn’s potentially life-giving moons — Titan or Enceladus.

So, appreciate every image that is captured by Cassini over the coming weeks. The pictures will be like nothing we’ve seen before of the ringed gas giant, creating a very bittersweet phase of the spacecraft’s profound mission to Saturn.

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Sol 3: Beautiful, Beautiful Mars Dirt. In Color.

Rocks and regolith strewn over the ground near Mars rover Curiosity. Credit: NASA/JPL-Caltech
Rocks and regolith strewn over the ground near Mars rover Curiosity. Credit: NASA/JPL-Caltech

It looks like rocks and dust, right? Actually, it resembles the dusty parking lot near a beach where my family used to holiday when I was young — a sandy, ruddy, dusty patch devoid of grass where cars had worn down the top layer of dirt, exposing smoothed rock underneath. However, this isn’t a parking lot. Actually, scrub that, it IS a parking lot — Mars rover Curiosity’s parking lot in Aeolis Palus, a remarkably smooth plain inside Gale Crater on Mars.

I don’t have an awful lot to say about these new high-resolution images that have just been uploaded to the Mars Science Laboratory (MSL) mission site except that I really wish I were a geologist! I get the feeling that these images from a never before seen region of Mars will keep geologists busy for some time to come.

As Curiosity undergoes a software upgrade preparing it for surface operations, we’ve been patiently waiting for the mission site to upload new images (beyond the color thumbnail teasers) of the surrounding area. And it seems that on Saturday night that happened. Here are some of my favorite views from Curiosity’s Mastcam:

Curiosity's sundial on its deck reads: "Mars 2012 -- To Mars To Explore"
Curiosity’s sundial on its deck reads: “Mars 2012 — To Mars To Explore”
Discoloration in the top soil in the location of a crater formed by Curiosity's Sky Crane rockets. Credit: NASA/JPL-Caltech
Discoloration in the top soil in the location of a crater formed by Curiosity’s Sky Crane rockets. Credit: NASA/JPL-Caltech
The deployed high-gain antenna. Credit: NASA/JPL-Caltech
The deployed high-gain antenna. Credit: NASA/JPL-Caltech
The crater rim and detail of undulating terrain -- possibly dunes. Credit: NASA/JPL-Caltech
The crater rim and detail of undulating terrain — possibly dunes. Credit: NASA/JPL-Caltech