Has it really been 10 years since the launch of the Cassini Saturn probe?
Wow.
To celebrate the anniversary, NASA has released a whole bunch of cool images and animations. They’re all incredibly beautiful, but how can you resist this one in particular?
[Click the images for much larger versions!]
There’s something about seeing Saturn from a height. Wow again.
I’m also fond of this one:
See the rainbow? In this image, the Sun is directly behind the camera. The sunlight hits the ice particles in the rings and gets refracted back toward you, making a bright spot in the rings. But why the rainbow? At first I thought it was a glory, but actually it’s an illusion! Cassini doesn’t take color images like your digital camera does. It takes a series of images with different filters which are then combined on the ground to produce color. As Cassini swept past this point over the rings, it took three images (red, green, and blue) which were then added together. Since Cassini was moving, the spot smeared out, and since the color images were taken sequentially, we see an elongated rainbow. We can also see yellow and other colors in the rainbow because the spot was big, bigger than the amount it got smeared out by Cassini’s motion. The right part of the spot in one image overlaps the location of the left part of the spot in the next image, so the primary RGB colors add together to get the secondary colors.
Kewlll.
This next one is incredible. It’s an animation of tiny Prometheus and its effect on Saturn’s thin F ring:
[To see this better, click the animation for a larger version.] Prometheus orbits Saturn every 14.7 hours in an ellipse. The top of the ellipse brings it just out to the orbit of the F ring particles. When it gets close, it pulls out a streamer of material. The camera stays centered on the moon, but the overall orbital motion of Prometheus and the ring is to the right. Prometheus, closer to Saturn, moves a little bit faster than the ring particles. As it pulls out the streamer of particles, they fall toward the moon and wind up orbiting Saturn a little faster than they did before. However, they still aren’t moving as quickly as Prometheus, and fall back to the left as the moon leaves them behind. The view is odd since the moon stays centered; if the point of view of the camera were stationary and everything swept past from left to right, it would look different. You’d see the actual elliptical motion of the moon as a big arc from left to right, and the ring particles would be seen moving that direction as well, just not as quickly as the moon does.
It all depends on your POV.
And that, BABloggees, is the whole point. We don’t go to these exotic locations in the solar system because we know everything that’s going on, or because we know what we’ll expect to see. We go because we don’t know. But we also go because we need to have our positions rattled, our notions shaken, our ideas tested. When we see Saturn from above, or co-orbit with a moon, or see a rainbow reflected in particles of ice a billion kilometers away, the only thing we can be sure of is that we’ll see new things, unexpected things.
That’s how we learn. That’s how we grow. And that’s what science does for us.
October 15th, 2007 at 10:29 am
Truly breathtaking photos. It’s almost eerie, Saturn is so much bigger than the pictures would give away. I can’t wait to see what Pluto looks like from the New Horizons probe.
October 15th, 2007 at 10:57 am
Lovely summary, Phil! Gosh, ten years went by fast… I remember when Cassini launched, and I couldn’t wait to start seeing the pics it sent back once it finally reached its destination!
Also, I love the last two paragraphs in this entry of yours! “We go because we DON’T know.” Perfect. And then you top it with this: “That’s how we learn. That’s how we grow. And that’s what science does for us.”
Now, if only we could convince more people of how right those statements are, and excite them just a little bit about our universe… I try each day, I really do, but it sometimes seems hopeless in light of the daily drivel–erm, news–the media keeps hawking, and the general public’s willingness to not care.
Ah, well. Thanks for illuminating the darkness a little bit!
October 15th, 2007 at 10:58 am
Great stuff! But where does this “diamond anniversary,” uh, stuff, come from? A little overhype, it seems. Since when is 10 years a diamond anniversary? It will be quite a step down in another 15 years when it’s “merely” a silver anniversary. I guess De Beers has to keep trying to grow demand for overpriced minerals!
October 15th, 2007 at 11:18 am
Ahh.
This is why I have this page bookmarked for daily reading.
October 15th, 2007 at 12:08 pm
“And that, BABloggees, is the whole point. We don’t go to these exotic locations in the solar system because we know everything that’s going on, or because we know what we’ll expect to see. We go because we don’t know.”
And how sad it is that said point is lost on so many people. Seeing this article reminded me of my father’s response to some announcement (long ago) about the unexpected structures that were found in Saturn’s rings. It was sort of a gleeful, “ah-HA! Those scientists don’t know as much as they think they know!” I can’t remember how I felt about that at the time, but I’m glad it’s just head shaker now.
But now–because we spent the money and time to go there and see what we could see–we know a little more about it. I’m glad that there are enough curious people to overcome the opinions of those that are afraid to venture outside the cave to see what we don’t know.
October 15th, 2007 at 12:12 pm
Actually, what leaps out at me from the first image is not seeing Saturn from above — we do sometimes get that view due to the planet’s inclination, though not to this degree.
No, what’s really different is seeing it from the *side*. We never get any view from here other than a “full Saturn”. It’s really amazing to see a crescent or gibbous view, something we never come close to from our usual perspective.
October 15th, 2007 at 12:13 pm
these two images are just… breathtaking. Saturn is really the most delicate looking planet in the system. I think that’s the best word for it; Delicate.
Pretty pretty and yet if you’d go on this thing you would die. How awesome is THAT?
October 15th, 2007 at 12:42 pm
Does anyone have the photo from cassini of the earth and moon in front of the sun?
October 15th, 2007 at 12:45 pm
Beautiful!
Every time I see the gorgeous Cassini images, I’m reminded of how much we lost due to the high-gain antenna failure on Galileo.
October 15th, 2007 at 12:51 pm
Oh. My.
The first ones were stunning – deer-in-headlights stunning.
But the animation just made my brain grind to a halt for a full five minutes. Indescribable.
October 15th, 2007 at 1:07 pm
>>It all depends on your POV.>>
And suddenly, the strangest things are happening. I hope it’s not the last time (last time).
[obscure?]
J. D.
October 15th, 2007 at 1:07 pm
I tend to agree with Eightman (how many others remember that cartoon?) – I was *really* enjoying the images – then I started to read the text and was brought up short. I realize the author was working to call attention to the length of time and the amazing amount of knowledge attained, but come on – 10 years is tin/aluminum (or jewelry, if you use the more modern and less interesting list). Last time I looked, jewelry != diamond, and diamond!= jewelry.
That having been said, those images are *amazing*! I *so* want to fly my megathron around out there and see this stuff with my own eyes!
October 15th, 2007 at 1:24 pm
You know, I was just listening to Holst’s “The Planets” and in particular the track “Neptune” was playing when I cam across these images.
The track and photos go pretty well together, although for complete symmetry Holst’s “Saturn” should have been playing…both tracks are hauntingly beautiful, although “Neptune†more so. Thanks for the links.
Great!
October 15th, 2007 at 3:13 pm
Lordy, I remember working at a McDonalds ten years ago, reading USA Today about Cassini’s launch on my break.
Which brought me to another thought — I remember sending the Bad Astronomer an e-mail about the movie Armageddon right after it came out, which was nine years ago (same “era” of my life) — good heavens! I’ve been visiting your site for almost ten years!!
October 15th, 2007 at 3:40 pm
I know the feeling: ten years ago, I was arguing with an idiot Oregonian about how the launch wasn’t going to lead to the entire planet being covered with plutonium dust if it failed. (Just as proof that there’s not an alternate energy source that a Portlander won’t lie about to prove his/her case, I was told over and over that Cassini didn’t need to launch with a nuclear reactor because “solar cells are now available that can more than handle Cassini’s needs”…and my biggest mistake was asking for citations on those solar cells.) A decade later, I’m in awe of these pictures, and this twit is probably still whining about how Cassini should have flown with imaginary solar cells if they’d just listened to him.
October 15th, 2007 at 3:57 pm
[...] 15th, 2007 Via Phil Plait, news that in observation of the 10th anniversary of the Cassini launch, NASA has just released a [...]
October 15th, 2007 at 4:02 pm
Amazing. Truly amazing. Thank you.
And this passage:
“We don’t go to these exotic locations in the solar system because we know everything that’s going on, or because we know what we’ll expect to see. We go because we don’t know. But we also go because we need to have our positions rattled, our notions shaken, our ideas tested. When we see Saturn from above, or co-orbit with a moon, or see a rainbow reflected in particles of ice a billion kilometers away, the only thing we can be sure of is that we’ll see new things, unexpected things.”
Captures perfectly why such exploration is so very exciting. Curiously, it could also be prophetic, were my novel fact rather than fiction.
Jim Downey
October 15th, 2007 at 6:07 pm
[...] Some terrific photos of Saturn (plus color commentary) here: http://www.badastronomy.com/bablog/2007/10/15/cassini-10-years-and-counting/ [...]
October 15th, 2007 at 7:51 pm
Seriously, they were so beautiful I thought they were paintings. I never figured we could get images with such clarity from the outer solar system! Go Cassini!
October 15th, 2007 at 8:34 pm
I woke up before 5:00 am to watch the launch. Spectacular night launch. The Plutonium controversy (there is about 80 lbs or so on board) definitely had a silver lining; excellent coverage of the launch. Missed in the hubbub was what an incredible mission it would be.
October 16th, 2007 at 8:08 am
Beautiful pix.
In the first one, is it an optical illusion that the
shadow looks smaller than the planet?
October 16th, 2007 at 10:51 am
The images from Cassini are amazing, and I know I’m not alone in thinking that. I have several for desktop backgrounds on the pc’s that I use. Fantastic!
Edward C. – I do think it’s an optical illusion, and someone may come along that can explain it better, but I think it has to do with perspective and the shape of Saturn.
October 16th, 2007 at 12:16 pm
Ten years of Cassini, ten years of my younger brothers, the best little skepdude twins in the known universe.
Happy Birthday, to all.
The pictures are amazing, and Cassini has certainly become part of my life.
Keep on keeping on, Cass.
October 17th, 2007 at 4:39 am
Those images are SO cool! The first one has now become my computer’s wallpaper, replacing a drawing of a Mars rover.
The animation of Prometheus and the F ring is truly amazing.
I’ve submitted the NASA site to Science Videos, in hopes that it gets added to the Space list.
October 18th, 2007 at 6:09 am
[...] ground observatories) to mark the occasion with. Aside from the obligatory retrospectives (like a nice one provided by the Bad Astronomer), the new data tends to fall into two categories — news about [...]
November 5th, 2007 at 11:05 pm
[...] Pictures of Saturn from the Cassini probe. [...]
February 9th, 2008 at 8:59 pm
Just amazing pictures, couldnt get up myself to see it
oh and happy birthday !
July 9th, 2008 at 8:07 am
Man, it’s crazy that nomatter how old you get this stuff still excites you and puts a major sense of awe in your bones. I really still love this stuff! It’s like you can be a kid all over again, just gazing at how amazingly beautiful all this stuff is. And, of course, you can’t help but ask the big questions and yet find some sort of solace in the mystery of it all. Saturn looks so beautiful – I wish I could see it up close and personal. It must be really awesome. Man, I need to save up and buy a telescope some day!