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Spacecraft to Fly Through Geyser Plumes On Saturn Moon
Riding with Robots writes "Today the robotic Saturn probe Cassini will make its closest buzz ever over the surface of the enigmatic ice moon Enceladus, whose surprising giant water geysers hint at a hidden ocean of liquid water. The spacecraft will fly right through the tops of the geyser plumes in order to sample the material that originated beneath the surface. NASA is offering a video, interactive guide and image gallery in advance of the event."
It can really analyse the water samples? Wow, I'm impressed.
NASA really wants the probe to get a wash down.
I should add that although the closest approach to Enceladus is happening as I type this, Cassini won't have a chance to turn its antenna toward Earth until later this evening (U.S. time). The downlink will take several hours, so the first pictures probably won't be publicly available until tomorrow.
Saddle up: Riding with Robots
I already sampled the water from the geysers on Enceladus back in '78 at a Greatful Dead concert.
Tasted kind of sweet with a hint of mint.
NASA needs to get with the times. They've got 30 years of catching up to do.
If they don't have wipers on their nice expensive spaceship isn't there a chance they could ruin the camera images with droplets and splattered bugs etc?
liqbase
Well, the initial plans called for wipers, but that would have required another .4 kg of expensive plutonium pellets in the RTG, and the added mass of the motor, intermittent-wipe controller, and the mechanism for changing spare wiper blades would have meant that the hermetically sealed capsule containing the Blob (frozen by Steve McQueen in the 1950s) would have been bumped to another deep-space probe.
Maybe it will find something like the andromeda strain.
Now, that would be something.
I remember the good old days when they'd tell you to rewrite your book report for talking about water in space.
"I guess I'm gonna fade into Bolivian."
Hats off to the JPL nerds who made this work. I am floored.
The pain was excruciating and the scarring is likely permanent, but that just means it's working.
That's no moon!
Also, since there's hydrocarbons on Titan and ice in the rings and moons of Saturn, I think Clarke picked the wrong gas giant to send his characters to! Saturn's got it going on.
This is not a sig
The spacecraft is flying 200 km from the south pole of Enceladus. The plume extends *thousands* of kilometers into space. We're not passing through the top of the plume by any means. We're getting right into it.
You all keep using that word. I do not think it means what you think it means.
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
I don't think NASA would put Cassini into any significant danger, considering that the probe is still doing a lot of good work. But think of the science being done here! This is why we should be putting more money into our robotic missions. We don't even need to qualify them by saying they can do some things more efficiently than humans, they can do things right NOW that we meatbags have no chance of doing for at LEAST another century!
Yes, it has thrusters. Midcourse corrections happen every now and then.
It's not so much that orbital mechanics is hard; a lot of it is just brute-force computation. The hard part is getting reliable data to base said computation on.
The meek may inherit the earth, but the strong shall take the stars.
All These Planets Are Yours Except Europa, Attempt No Landing There ...
I know it's not Jupiter
Success is not the result of spontaneous combustion, you must set yourself on fire.
Getting good data is hard, but good course planning is also hard. It's easy to find an orbit that will work; push an object sideways around a mass at any of a wide range of velocities, and voila, it's in an orbit.
What's hard -- and really as much an art as a science -- is taking the laws of orbital mechanics, the very restricted maneuvering-fuel budget, and several thousand science goals (often mutually excusive), and turning them into an efficient mission plan.
Then add to that dealing with the unexpected. The Cassini team had a whole orbital tour worked out before launch, then discovered while the probe was already en route to Saturn that they needed to completely change the orbital geometry for the Huygens probe's Titan descent to compensate for a radio design snafu. They succeeded in not only rejiggering nearly all the planned science to fit into a new orbital tour, but also in grabbing a few resulting new opportunities for observations along the changed route.
The best analogy I can think of is to the difference between generating a set of legal chess moves, and a set of good chess moves.
When all you have is a hammer, everything looks like a skull.
Very true, although it's a bit more complicated still: chaos pretty well guarantees that even if you plan out a great trajectory in advance, you'll drift and end up in trouble down-stream. Plus there are inevitable changes required due to problems (like with Huygens or changing models of the Titan atmosphere) ...
It's not so much "trouble", but rather using up more course adjustment fuel to compensate for errors in reality versus the model. After every moon pass-by they can use the cameras to check the probe's orbit against the model, and make adjustments with small rocket firings. The less fuel you have, the shorter the mission and/or less chances to change your mind.
But Cassini is on an amazing pinball ride.
Table-ized A.I.
needed to completely change the orbital geometry for the Huygens probe's Titan descent to compensate for a radio design snafu.
That's an amazing story in itself. The dude who discovered the problem did it on a hunch, barely got funding to check into the issue, and was almost ignored when he uncovered the problem. It would make a great "nerd drama" movie.
Table-ized A.I.