Captain’s Log
November 12, 2013

Four months ago, our cameras on Cassini were commanded to execute a routine imaging sequence during an event that was anything but routine.

On July 19, an array of overlapping images framing Saturn, its entire ring system and a host of its moons was acquired while Cassini was deep in the shadow created by the planet’s eclipse of the Sun.  This arrangement of Sun, Saturn, and machine made for a rare opportunity to image from the outer solar system the planets in close to the Sun. The intent:  To catch a precious glimpse of our own planet … tiny, remote, alone … as it would be seen from a billion miles away.

Images of this nature had been taken before.  The famous Voyager 1990 ‘Pale Blue Dot’ image of Earth  became, in the hands of Carl Sagan, a romantic allegory of the human condition and an inspirational call to environmental protection and planetary brotherhood.  And Cassini’s previous 2006 version, taken from Saturn orbit, showing the startling juxtaposition of our dot of a planet beside the enormity of Saturn’s rings, became the most beloved Cassini image.

But from the very start, the plans for the July 19 mosaic included something very special:  If all went well, the images would capture a glimpse of Earth alongside Saturn and its rings at the very moment that people all over the globe would be contemplating their connectedness to each other and to all life on Earth, appreciating the rarity of our planet within the solar system, marveling at their own existence, and rejoicing at the very thought of having their picture taken from a billion miles away.

And contemplate, appreciate, marvel and rejoice they did!

From Pennsylvania: 'What a great way to feel connected to the universe, the planet, and every single person on it. We are truly all in this together.’

From England: 'What a privilege to be part of such an event with so many people world-wide.’

From somewhere unknown: 'At the appropriate time, I turned my face to the sky & spent a few minutes watching & listening to what life on Earth was like, right there. What a feeling of connection and oneness with the miracle that is life on Earth. This experience was beyond meaningful. It was transcendent. What a beautiful thing.’

From upstate New York: 'I’ve been entranced by this project ever since I heard about it and was determined to join in the celebration. We may not be unique… we may be transient… we may be only flying along on a dust mote. But for 15 minutes we were there, we were aware, and we smiled.’

After much work,  the mosaic that marks that moment the inhabitants of Earth, including the four above, looked up wherever they were and smiled at the sheer joy of being alive, is finally here.  In its combination of beauty and meaning, it is perhaps the most unusual image ever taken in the history of the space program.

Have a look and you will discover a universe of marvels. The brightly rimmed globe of Saturn and its main rings aglow with sunlight streaming through them take center stage. On the left, embedded in the enormous, gossamer blue E ring, is the brilliant moon Enceladus, gleaming in the reflected light of Saturn and the sparkle of a hundred towering geysers, and likely the most promising place in all the solar system to access alien life.  A careful examination uncovers the shadow cast by this moon through the spray of smoke-sized icy particles created by those geysers, like a telephone pole might cast a shadow through a fog.

Below and to the right of Enceladus is Tethys, a moon about a third the size of ours, illuminated by Saturn-shine. On the other side of the planet, to the upper right,is Mimas … only a crescent but also casting a faint shadow through the E ring.

And on it goes … more moons and faint rings for anyone caring to take the time to wander.

Now, look one more time. There, below the main rings and to the right of the globe of Saturn, far in the distance and seemingly lost in the radiance of the scene, lies a small speck of blue light, floating in a sea of stars. That is our home, with every last one of us on it … you, me, the folks down the block, even those on the opposite side of the Earth … we all inhabit that lovely blue dot.

And more than this … the image of that dot captures the very moment, frozen in time, when the inhabitants of our planet took a break from their normal activities to go outside and acknowledge our 'coming of age’ as planetary explorers and the audacious interplanetary salute between robot and maker that this image represents.

I hope long into the future, when people look again at this image, they will recall the moment when, as crazy as it might have seemed, they were there, they were aware, and they smiled. The Day the Earth Smiled

carolyn porco on Flickr.

Via Flickr:

carolyn porco

19cm x 14cm limited edition gocco print edition of 40.

warp link text

Carolyn Porco is one of my favourite planetary scientists. In additional to her major roles in my favouirte Voyager and Cassini missions she is a great communicator. Her passion and ability to share amazing concepts and findings is inspiring.…


Happy Birthday to Carolyn Porco, lead scientist for Cassini’s imaging science team and all around amazing planetary scientist and science ambassador.  

In honor of her birthday, here’s a round-up of Saturn-themed items we’ve featured on our blog.

Top panel: Saturn dress, Final Frontiersman t-shirt design, Saturn paperweight, aluminum cuff bracelet.

Bottom panel (clockwise): Saturn celestial buddy, Saturn tree ornament, Saturn dinner plate, Solar System vase.

The photo at the start of this post was taken by the Cassini spacecraft in November 2013 looking back at the inner Solar System, as Saturn transited in front of the Sun. It was part of a campaign pioneered by Carolyn Porco as “The Day the Earth Smiled” (aka pale, blue dot 2.0).

- Summer

In this week’s mind- and soul-expanding vista from Cassini, Saturn’s moons Mimas and Dione, worlds with stories to tell, are dwarfed by their regal patriarch.

I will so miss these tidings when Cassini’s travels are over.

Two more years. We have two more years.

Enjoy! Looking Up to the Giant

The last two episodes of Cosmos were glorious and actually made me look at myself differently.

Being more scientist than historian, I never knew of Cecilia Payne. And now I discover she, too, said this:

“The reward of the young scientist is the emotional thrill of being the first person in the history of the world to see something or to understand something. Nothing can compare with that experience… ”

So true, Cecilia. So true.

And I never knew of Marie Tharp, either. It’s telling that I was educated in the Division of Geological and Planetary Sciences at Caltech, had certainly heard in reverent tones the story of Alfred Wegener, but had never even heard the name of Tharp.

Many grateful thanks to Ann Druyan, Steve Soter, Neil deGrasse Tyson, and the Cosmos crew for bringing to light the stories of these women greats of astronomical and geological history.

And to my fellow female scientists, I hope you now see yourselves differently, too. You and I are part of a fine & noble lineage. Walk tall and proud forevermore.

We on Cassini received wonderful news today. In a review this past summer of all the 7 NASA missions seeking to extend their operations for several more years and requesting additional funding to do so, Cassini was the only one of them receiving an unqualified `Excellent’ for its science and future plans. So, we are now gratefully anticipating another 3 years of exploration, with mission operations ending on September 15, 2017 with a dramatic nose-dive into the planet.

How wonderful it is to know that we will live out the full, unabridged promise of this extraordinary mission. For many of us, for the past quarter century, it has been a way of life. For many of us, its end will mirror the end of a major portion of our life’s work.

But this is no time to get sentimental. We now are looking forward to 3 more glorious years of new discoveries and insights, three more close flybys of Enceladus, flights over the Saturn pole and through the rings, and, of course, many more of the most soul-stirring, magnificent vistas there are to be seen anywhere this side of the Oort cloud.


Science/AAAS: NASA extends seven planetary missions

Today, the European Space Agency released an image taken by the Rosetta spacecraft on its very close (8.7 km altitude) flyby of Comet 67P. This mind-blowing scene shows details as small as ¾ meter. You could discern astronauts in an image like this! It reveals a portion of the comet 1.3 km, or ~¾ mile, across….an easy 15 minute walk here on Earth and a trivial (but scary) hop on Comet 67P.

Even as someone who has seen, and even been responsible for, a lot of glorious images of the worlds in our solar system, I am stunned by these pictures. Our pre-exploration imaginings of what the surface of a comet might be like were so lacking.

Now, look at all there is to see and learn in this place where complicated processes have obviously worked the surface. Hats off to the Rosetta folks for a magnificently successful expedition.


One of the many intriguing findings that our Cassini cameras have made at Saturn has been the long, sinuous, finger-like projections emanating from the geysering moon, Enceladus, into the diffuse E ring in which the moon orbits.
Now, I’m happy to say that my research colleagues and I have published a paper online, in the Astronomical Journal, reporting the origins of these features in the strongest geysers erupting from the south polar terrain of Enceladus.
See for yourself in our new report how well we are able to match the structures of the tendrils with our computer simulations of icy geyser particles leaving the surface of the moon.

This result will ultimately give us a way to estimate the amount of material leaving the ocean of Enceladus and making its way into orbit around Saturn, and from there, just how long-lived the ocean may be.

As you can see, we’re still going strong, and will be til the end! Enjoy! Finger-like Ring Structures In Saturn’s E Ring Produced By Enceladus’ Geysers


How sweet it is! Richard Branson plans to smile on July 19 w/ the rest of us!!

He says:

“One of my favourite images is the Pale Blue Dot, a photo taken in 1990 that captured the Earth as a tiny speck of light from beyond the orbit of Neptune.

Then in 2006 Cassini took this awe-inspiring image of Earth from within the shadow of Saturn. Can you spot us?

Now it is time for an updated version of the Pale Blue Dot. On July 19th, the Cassini cameras will face the sun and capture the Earth, Saturn and its rings. It will be the first time human beings have known in advance their photo will be taken from a billion miles away.”

Richard is also promoting the two contests we are running at Diamond Sky Productions. If you are a photography buff who has thought about communication with extraterrestrials, or you are a music composer, consider entering!

Richard’s Blog - Pale Blue Dot

I am finally free to shout this one out loud…..

Yesterday a team of us scientists and engineers submitted a proposal to NASA’s Discovery program. The goal: To conduct a mission back to the Saturn system and search for life within its small icy moon, Enceladus! Since all details concerning the mission are still embargoed, and will be until we are selected … if we are selected … I am not free to divulge how we intend to go about this search. But I can say that we will be doing what Cassini cannot, and may in fact be employing diagnostic techniques never used anywhere before in the exploration of the solar system.

I thrill at the thought of it.

When I was a graduate student, moons like Enceladus, and even Titan — both seen in the image here — were mere points of light in the world’s largest telescopes. Forty years later, we’ve been there and know the tantalizing possibilities that are present but hidden and just out of reach.

If our mission is chosen, we may have the chance to make the most intellectually significant and emotionally satisfying discovery humankind has ever made: That a second genesis has occurred in our own backyard and, by inference, that life is not a bug but a feature of the universe in which we live. A look up at the night sky thereafter will never be the same.

Wish us luck!


A Letter to My Friend and Colleague, Carl Sagan, on the Occasion of His 80th Birthday

November 9, 2014

Dear Carl,

It’s so lovely to be beaming this message to you on your 80th birthday.
As you may be aware, the world hasn’t changed much since you left. It’s still a great mess. It’s still looking like we may destroy our civilization after all. Political gridlock is as bad as anyone can remember, and there’s no end yet in sight to the damage we are doing to our environment and our future. Regrettably, in the hallways where power congregates, they are still not listening to you..

But I gotta tell ya… Titan was even more wonderful than even you could have imagined. Seas of liquid hydrocarbons are strewn around the poles. Methane clouds that change seasonally float aloft. And a wide belt of miles and miles and thousands of miles of dunes encircle the globe. Who expected that?! So much like Earth and yet so not.

And you wouldn’t believe what we found on Enceladus! A hundred and one geysers gushing from the surface, laced with organic compounds and erupting from a deep salty sea. It just might be the very place you wished with all your might we could find. Someday, hopefully soon, we may know if…well…you know. Fingers crossed.

And now we’re on the eve of exploring the Kuiper Belt, starting w/ a most historic rendezvous with Pluto, and in only a few days we’ll be landing on a comet. We’ve made great strides in our efforts to know how and where we are. I know all this would have made you smile and would have given you great hope. Just wish you were still here to cheer us on.

Oh, and didn’t Annie do a great job with Cosmos II? You would have been so proud.

Well, wherever you are right now, undoubtedly out there somewhere in the cosmos, having a blast, the happiest of Happy Birthdays to you!

We miss you.

Your friend and colleague,

PS. Sending along some pictures from happy days … at Voyager’s encounter with Neptune in 1989, and your 60th birthday party twenty years ago. How time flies.


With northern spring on Saturn’s Earth-like, haze-enshrouded world, Titan, now fully in swing, and the cloudy days of polar winter far behind, the lakes and seas of liquid methane and ethane we earlier discovered dotting the moon’s north polar region have finally come under the watchful gaze of its sensitive, infrared-capable instruments.

New images taken by these instruments of this newly-illuminated region show many of these northern liquid bodies surrounded by bright material not seen elsewhere on Titan. Is this an indication that with increased warmth, the seas and lakes are starting to evaporate, leaving behind a deposit of solid organic matter … or, in other words, the Titan equivalent of a salt-flat? Time will tell.

But how thrilling it is to still be uncovering new territory on this fascinating moon … a place that, until Cassini’s arrival at Saturn nearly 10 years ago, was the largest single expanse of unseen terrain we had remaining in our solar system. Our adventures here have been the very essence of exploration. And it’s not over yet! Cassini Sights Titan’s Northern Land of Lakes