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Cassini Alters Path. Phoebe Now In Sight!
Anonymous Explorer writes "This week the Cassini-Huygens
Spacecraft finally entered
the Saturn system and made its first
main-engine burn in five years in preparation of for the Phoebe flyby. This long
journey
has been one filled with much promise and peril. Launched in 1997,
Cassini is expected to have a rendezvous with
the moon Phoebe
on June 11. For those of us who are lazy, that's just a tad under two
weeks away. After the Phoebe flyby, it's on to the ringed planet, with an
anticipated July 1
ground orbit insertion. The ESA's
Huygens probe will descend into the atmosphere of Titan a few months
after Cassini is inserted into orbit. This mission
promises to be
one that brings a very psychedelic and beautiful area of our solar
system into clearer focus. This multinational
mission is one the
most ambitious scientific explorations yet undertaken and promises some
truly otherworldly images in the near future. With 31 moons/natural
satellites thus far discovered orbiting Saturn, there should be a lot
to keep us occupied. Anyone else excited about the journey
to a ringed world? Lets all enjoy this ride. It promises to
be a unique one as much as for the scenery as for the science. Informal
discussion regarding the Cassini-Huygens mission can be found at
#cassini on irc.freenode.net."
to keep her head down 'round about the 11th.
She gets a little freaked when things flyby without warning (although I've rather been looking forward to it myself).
I'm still trying to figure out though, why I, as the more massive of the pair, appear without question to be the captured object.
KFG
I predict they'll get some footage like this.
while we are talking about Cassini, let us remember the protesters who were so opposed to it.
Remember cassini is nasa's deadly space probe. It is nice to see that these groups have other stuff to protest these days. Hope that stuff is not as deadly as cassini...
The war with islam is a war on the beast
The war on terror is a war for peace
This mission promises to be one that brings a very psychedelic
Guess the mission engineers took the brown acid. Bummer.
bash: rtfm: command not found
Map and Images of Titan from Hubble Space Telescope
Nasa Titan Photojournal
Saturnian Satellite Fact Sheet
Phoebe best image so far, from Voyager2 in 1981!
Do you need a website upgrade?
It's gonna be nice to see a photo-intensive orbiting mission to one of the big gas giants. The Galileo orbiter for Jupiter had an antenna problem that greatly reduced the imaging volume.
However, based on Voyager flybys, Saturn's moons are not quite as photogenic as Jupiter's. Titan is covered with a thick feature-poor haze and most of the other moons are too small to have many of the interesting tidally-caused features of the Jupiter moons. But there are still some interesting features on some of the moons.
And, Cassini will drop a probe into Titan's atmosphere that should return some interesting images and data. Titan may have a methane ocean and the Titan probe may possibly land in it and float for a few hours. The ocean may have giant waves because the gravity is so weak compared to Earth, similar to the way that sand-dunes are easier to make on Mars because of the lower gravity there. Things can get taller and weirder under low gravity. It would be the first time liquid could be seen from the surface of another world (aside from the Apollo Tang drippings).
Table-ized A.I.
I more than half expected the channel to be Slashdotted, as happens to all websites when their address is mentioned here. But strangely, there are only about ten people over there right now.
On another note, I am very excited about the upcoming part of this mission. I was finishing high school when they launched this thing, and when they talked about it, it seemed like it would be forever before that thing reached Saturn. Needless to say, it has been a lot less than forever.
I wish the fine engineers at Nasa the best of luck in accomplishing this portion of the mission.
After the Phoebe flyby, it's on to the ringed planet
All the gas giants have rings, not just Saturn. They're not as easy to see, but they have been detected.
Learn something new.
IMHO quality images do more to create and maintain public enthusiasm for space exploration than all the statistics in the world about the benefits of the space program; far too many geeks and/or scientists underestimate and underutilize the best of all marketing tools we have for getting funding and support for the space program. I hope they don't forget about the value of a pretty picture.
"Everyone is entitled to their own opinion, but not their own facts."
Cassini is expected to have a rendezvous with the moon Phoebe on June 11. For those of us who are lazy, that's just a tad under two weeks away.
Does this mean that those of us who are not lazy have to wait a few more weeks before we can learn about Phoebe's observations?
Phoebe best image so far, from Voyager2 in 1981
"My God! It's full of pixels!"
Table-ized A.I.
I think astronomers realize the importance of beauty when trying to get public support. Check out the Hubble Heritage project. The main reason for this project is to take pretty astronomy pictures.
I know you're just going for a lame joke, but for the record, Uranus does have rings.
This, as we all know, is the spaceship equivalent of a middle aged man gettin' some for the first time in a long while.
http://www.rootstrikers.org/
Does anyone else think its amazing that the thing actually works after five years of no activity? Seriously, I wouldn't trust my router, cable modem, or toaster (all devices of comparable embedded computing power) to run nonstop for five years. I think it speaks well for the Nasa engineers, and the things they actually do right. Its a shame only their mistakes make the news.
Even those who arrange and design shrubberies are under considerable economic stress at this period in history.
Can't believe how much I'm looking forward to this. It's going to be exciting to learn more about the rings (especially the F-rings perhaps), Saturn itself and then the landing on Titan. It's a good thing there are so many mysteries out there, or the world would be a bit boring.
Funny, I never post AC. It says something about a person's character when they will only be controversial when they are not held accountable.
Anyway, I didn't say "environmentalists" are stupid. Most mean well, and some are even well informed and productive. Unfortunately, many mistake passion for evidence, and can't be bothered to investigate opposing viewpoints.
RTGs are hardened and designed to withstand explosion and extreme temperatures. They do not explode, and I believe that they do not even become active until after launch. Radiation has been "The R Word" since the 50's, but we actually use it all the time and know how to handle it. Only in cases of extreme incompetence and lack of precautions (see Chernobyl - 1986) do we need to be concerned.
Returning to the planet, a nuclear plant is far less likely to cause ANY harm than most power technologies or chemical processes (See Bophal, India). We KNOW that radiation can be dangerous, hence the extreme precations we take.
Incidently, NOTHING is 100% safe... along with fearing (and guarding against) the risk, you should consider the rewards.
"Faith: Belief without evidence in what is told by one who speaks without knowledge, of things without parallel." - A.B.
Remember cassini is nasa's deadly space probe. It is nice to see that these groups have other stuff to protest these days. Hope that stuff is not as deadly as cassini...
The protests were about a risk, that is, an accident that could have occurred with a certain probability. Everybody pretty much agreed that the risk of an accident was at least fairly low. What people disagreed on was the cost should such an accident acctually occur. The fact that a fairly low-risk event didn't occur does not tell you anything about whether it was prudent to engage in the activity in question.
I'm sorry that such elementary scientific and economic concepts as "risk" and "cost" elude you. Without an understanding of those concepts, you are simply in no position to even participate in such debates.
Given that the rings are made up of lumps of rock and ice, how do you avoid them? Will Cassini orbit inside the rings? Outside? Or does it have a bulldozer plough on the front to just barge it's way through?
"first main-engine burrn in five years"
...
[only a] 78 mph change in speed
One thing that comes out again here, but only by implication, from these reports, is the amazing accuracy and precision (still amazing to me anyhow) of the ephemerides (~ solar system maps) used to plan these missions. They knew where Mars would be for MER to within, what, was it about a meter or two? Maybe not that close for Saturn but still good enough not to need main-engine course corrections in five years
Kudos to the chief JPL mapmaker Dr Myles Standish and his crew!
-wb-
I AM an environmentalist, and I KNOW that there was more danger with the rocket (bomb) that was sitting under Cassini hurting people than the RTG becoming a problem. IF the RTG did somehow become a problem, the "probability * consequences" was still so low that it's more dangerous for you (and the rest of the world) to drive your car to work. The issue is that there are some rather uninformed emotional reactions to the word "radiation".
Do you drive a car? Do you use a computer? Do you smoke? All of these have very real and very bad risks to yourself and others. Nothing you do is 100% safe. You're still doing it.
The problem is not that you oppose nuclear power, it's that you seem to be uninformed about nuclear power (and the rest of technology). The "risk" associated with your using electrical energy to power your computer is more than the risk NASA generates by using an RTG to power a spacecraft. The environmental consequences of burning coal, damming rivers, or however else you produce your electricity are much worse than the use (or even (VERY unlikely) destruction within Earth's atmosphere) of an RTG.
This doesn't mean they're dangerous. They are all quite capable of surviving reentry and impact, and in one case (the NASA Nimbus B1 satellite in 1968) an RTG was recovered and actually reused in another spacecraft!
Furthermore even if one did break up in the atmosphere and somehow vapourise despite being made in a ceramic form that would stay in a few lumps, it would cause bugger all damage. Plutonium isn't especially radioactive, although it is moderately chemically toxic. The small amount in an RTG completely pales in comparison to the plutonium in the environment from all the nuclear tests, and those make up literally 0.5% of the radiation we receive each year. (The rest comes mostly from natural sources but a significant amount also from medical xrays.)
"Studies have shown that people who eat peanuts live longer than those who do not eat."
Oh, nonsense. All evidence says that RTGs are very safe. Therefore someone saying that they are not has the burden of proof. Whether or not a person _likes_ the truth (or our best estimation thereof) doesn't change it.
The greater damage was done by irrational fearmongering than any launch.
This silly thing where "my side need only be plausible, your side needs to be 100% concrete" is stupid. I think we're done.
"Faith: Belief without evidence in what is told by one who speaks without knowledge, of things without parallel." - A.B.
Wake me up when we plant a flag on Jupiter.
They're also really damn expensive because you have to make the fuel in a nuclear reactor. Probably not suitable for home use. Also, there hasn't been much success making them really really tiny like you'd want for portable equipment.
"Studies have shown that people who eat peanuts live longer than those who do not eat."
... about the journey to a ringed Apparantly not, we're having the same old discussion about that hazards it posed for having a nuclear power source, and dumb jokes about a character on a defunt sitcom. Perhaps it would save some bandwith on /. if mods just decided to forgo future Cassini stories. Those who want to see the pictures know where to go.
For those of you interested in Saturn's larger roll in the formation of our solar system, check out this site. Lots to read, but pretty interesting:
http://www.jnocook.net/saturn/
The ring plane extends out to infinity, and so even the Earth passes through it occasionally. The ring plane is considerably tilted with respect to the ecliptic, so it would have been impossible for the Voyagers to not pass through the ring plane. Both went well outside the rings, not, as you imply, through the rings (In Saturn radii: closest approaches V1=3.09 & V2=2.67, outer ring lies at ~2.3) Someone has already pointed out your misinformation about the Cassini orbit. Your links are interesting, but none support your assertions.
"I'm so moist I'm sticking to the leather." -Kermit the Frog on The Late Late Show
We have a room on the irc.freenode.net servers called #cassini which is available to all who are interested in the Cassini project. Here you will find a wide range of interests discussed, from the informal to the most scientific details of the mission. Some of the Cassini staff have shown interest in participating to further support the project's public interest so don't be surprized to meet them there.
We also support the ' Maestro ' program which is the Public-Outreach software created for the Mars Exploration Rover Project from JPL . As a result, we helped maintain the #maestro room (also on freenode.net) which is still in operation today.
With such high interest building as Cassini-Huygens approaches orbital insertion and the Phoebe flyby, we expect a bigger rush in the next weeks. Join in and share the experience!
If you are not sure how to do 'IRC' there are many good primers online to help and you can visit http://freenode.net for details about connecting as well as links to assist you to set things up to chat online.
See all "/.'ers" there... ;^)
Pandelirium
http://www.pandelirium.net irc.freenode.net
#cassini
#maestro
#pandelirium