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Cassini-Huygens Saturn Orbit Insertion Imminent

Anonymous Explorer writes "Fresh off of its fly-by with the Saturnian satellite Phoebe, the Cassini-Huygens craft is set for Saturn Orbit Insertion on June 30, 2004. Cassini-Huygens has a planned four year mission ahead for Saturn and its many moons. With 450 watts of power for the electronics, this mission has plenty enough horses to run the stretch with plenty-o-pep to spare. Thanks to all that power, and the plethora of electronics on Cassini and the Huygens probe, we can now hear sounds from Saturn. Pretty cool stuff! Festivities are scheduled to begin on June 29th with a broadcast of Cassini Saturn Orbit Insertion Press Conference on Nasa TV. SOI [PDF link] will occur after Cassini fires its main engine for 96 minutes, in order to slow down and be grabbed by the pull of Saturn. As always we extend an invitation to everyone to join #cassini on irc.freenode.net and help us celebrate this historic mission."

205 comments

  1. 450 watts? by sirboxalot · · Score: 5, Funny

    I have the same amount of power in my computer's power supply. Something seems fundamentally wrong with that.

    1. Re:450 watts? by lukewarmfusion · · Score: 1

      Yeah, it means that your computer is inefficient and power-hungry.

      Of course, if you had a team of people working to make your computer as efficient as a Saturn probe...

    2. Re:450 watts? by umrgregg · · Score: 3, Funny

      Damnit! When I sent in my fabrication designs I told them that they needed to run at least 1.21 gigawatts through the flux capacitor to uh... Well, that's... Nevermind.

      --
      NMG
    3. Re:450 watts? by phorm · · Score: 3, Informative

      I searched through the various articles trying to find that number, but no go. Maybe they're missing a zero... or perhaps 450W is actually a lot on a system that is likely drawing continuous power off a solar panel/battery.

      Considering the computer power needed to go to the moon, it's not likely that this thing needs an 3.2Ghz processor and GeForce :-)

      My Epia-M is plugged in taking about less than 30W of power (including HDD and DVD-ROM)... so really the equivilent of an efficient 1Ghz processor wouldn't need anything near your desktop machine's draw.

    4. Re:450 watts? by falzer · · Score: 5, Funny

      > Something seems fundamentally wrong with that.

      Like watt?

    5. Re:450 watts? by Fouquet · · Score: 5, Informative

      That's a bit low, but not too far off. Cassini uses 3 RTG power sources to generate the ~700-800 W necessary for the science instruments. Solar cells are not practical at that distance.

      This PDF file details the power supply situation on the spacecraft.

      It's pretty remarkable how little power spacecraft like this consume (and I'm pretty sure that Cassini is the most power hungry of the 'outer-solarsystem' probes NASA has launched).

    6. Re:450 watts? by OhHellWithIt · · Score: 1
      I was thinking the same thing:
      450w / 746 = 0.6 hp

      Granted, that's more horsepower than my table saw, but only just barely.

      --
      "Who controls the past controls the future. Who controls the present controls the past." -- George Orwell
    7. Re:450 watts? by khallow · · Score: 1

      Well, your computer's power supply isn't in orbit around Saturn. That's the difference. It's incredible work to put a power source there. And as far as space probes go, 450 watts is ample.

    8. Re:450 watts? by Rei · · Score: 1

      Not necessarily; power supplies adjust themselves for how much of a draw on it there is. It just means that it is *possible* that the poster's computer is inefficient and power hungry ;)

      --
      I'm an owl exterminator!
    9. Re:450 watts? by Rei · · Score: 4, Interesting

      Cassini is powered by the heat of decay of plutonium creating a variation in temperature across a junction of two different metals, which creates electric power (thermoelectrics). It's called an RTG: Radioisotope Thermoelectric Generator. They're not very efficient, but you try carrying a pebble bed reactor into space and operating it by long-distance remote control in zero g..... ;)

      --
      I'm an owl exterminator!
    10. Re:450 watts? by Rei · · Score: 4, Informative

      RTGs decrease in power production over time (since we're dealing with half lifes here). It has three RTGs which, initially, produced 285 watts of power each. With a half life of 87 years for Pu238, they should be somewhere around 250 watts each currently, so that sounds reasonable...

      --
      I'm an owl exterminator!
    11. Re:450 watts? by Jott42 · · Score: 1

      According to the press kit, the power from the three thermoelectric generators should be at 750 Watts. In addition 82 radioisotope heaters are used, each giving about 1 watt of heat.

      The communication with earth is achieved by a 20 W amplifier at 8.4 GHz and a 4 meter parbolic dish antenna.

    12. Re:450 watts? by Superfreaker · · Score: 1

      That means, neither you, nor the probe, are able to run a P4 processor reliably. Now that is scary...

    13. Re:450 watts? by EvilTwinSkippy · · Score: 1

      Yeah, but you aren't just powering the computer. You are also running all the radio equipment, sensors, and supporting electronics. And also remember that a lot of the supporting electronics are fault tolerant, so you are running 3 times what you need, all on hardware designed in the early 90's.

      --
      "Learning is not compulsory... neither is survival."
      --Dr.W.Edwards Deming
    14. Re:450 watts? by phorm · · Score: 1

      Just so. Unless they're going with USB2.0 for all the peripherals, I'm guessing that such a setup doesn't really compare to the desktop PC. Heck, even (as mentioned VIA vs AMD vs Intel) many PC's don't compare overly well... so I'm sure that 450W could be a reasonable number for whatever they're running.

      Besides, part of the power of a PC is the flexibility (it can be a calculator, gaming rig, media box, etc etc). With a specialized piece of hardware such as a satellite, I'm sure that having there are more rigid boundaries as far as what it needs to do, and thus power consumption.

    15. Re:450 watts? by brian728s · · Score: 0

      Wow, thanks for giving me the heads-up. I thought my 2.4c pentium4 system was stable, what with almost no crashes, but now I know better. Its measely 350 watt supply couldn't possibly be fully powering it.

      There is no reason to need a 450 or higher psu unless one of two things happens:

      1) You buy a cheap psu. They can't handle loads up to their rating. Your 450 watt cheapie is worse than my 350 watt antec psu.

      2) Your computer costs more than your house. Dual processors, every drive bay full, latest nvidia cards running in sli, etc, etc.

    16. Re:450 watts? by daeley · · Score: 1

      I think he means the probe has more than amp-le power.

      --
      I watched C-beams glitter in the dark near the Tannhauser gate.
    17. Re:450 watts? by Teddyman · · Score: 1

      A pebble bed reactor? We call that a sauna around here.

    18. Re:450 watts? by Anonymous Coward · · Score: 0

      Jigawatts damn it! Jigawatts!

    19. Re:450 watts? by Superfreaker · · Score: 1

      350 watts without constant rebooting?

      You must not be using liquid cooling or have l33t neon strobes hooked into your sound card outs!

  2. Sounds of Martian Life?!! by dukeluke · · Score: 1, Funny

    Wow - does that mean we can actually hear and thus potentialy decipher and understand what the martians are saying in their native tongue on the Red Planet?? -- Perhaps we can master the language so that when they come to visit us - we'll understand that they're saying "Don't Feed the Humans" rather than "Eat them!"

    1. Re:Sounds of Martian Life?!! by mschiller · · Score: 1

      Try Saturanians.. Cassini is at Saturn.. Not Mars...

    2. Re:Sounds of Martian Life?!! by Apocalypse111 · · Score: 1

      Well, if the probe were orbiting MARS, then we might be able to listen in to the MARTIANS, but since its orbiting Saturn, which is a gas giant (and incapable of supporting life as we know it) then I think we'll be just straining our ears if we want to hear Mars.

      --
      There is no mod option "-1: Disagree" for a reason. "Overrated" is not an acceptable substitute. Post something instead.
    3. Re:Sounds of Martian Life?!! by dukeluke · · Score: 1

      Oh yes .... my bad ;-) --- lol, I got hung up on the sounds part and forgot the article said saturn not mars :-P

    4. Re:Sounds of Martian Life?!! by EvilTwinSkippy · · Score: 4, Funny
      Hey, Americans have a hard enough time finding Canada on a map. Other planets are WAY beyond that.

      /Yes, I'm hitting on my own gang

      --
      "Learning is not compulsory... neither is survival."
      --Dr.W.Edwards Deming
    5. Re:Sounds of Martian Life?!! by mschiller · · Score: 1

      You have a point.. But in this case we aren't asking to FIND saturn. The takes some skills many american don't have. Here a dumb american only needs to recognize that Mars is not the same place as Saturn.

      FWIW, I am a dumb american...

      -- Matthew Schiller

    6. Re:Sounds of Martian Life?!! by Anonymous Coward · · Score: 0

      Hey, Americans have a hard enough time finding Canada on a map.

      We here in Canada don't mind. It keeps us from being invaded.

    7. Re:Sounds of Martian Life?!! by ari_j · · Score: 1

      We'd find Canada a lot quicker if you just called it by its real name: "Hat". Or "Toque", in the Canadian native language.

    8. Re:Sounds of Martian Life?!! by WormholeFiend · · Score: 2, Informative

      Actually, canada is an aboriginal word that means village.

    9. Re:Sounds of Martian Life?!! by linuxbikr · · Score: 1

      Most folks can't find their hometowns on a map. Hand someone a astronomical chart and tell them to find Saturn in the sky and they'll look at you blankly. Same goes for Jupiter, Mars and Venus (three easy planets to spot). Mercury is tough.

    10. Re:Sounds of Martian Life?!! by ari_j · · Score: 1

      Shh! Facts aren't welcome here!

  3. Not even 0.5kilowatts.. by Anonymous Coward · · Score: 4, Interesting

    ..for transmitting from millions of miles away and some HAMs are using 10 kilowatts upwards just for transmitting earth-to-earth!

    1. Re:Not even 0.5kilowatts.. by PhilippeT · · Score: 0

      Yes but HAMs don't use enormous receiving arrays

      --
      A psychopath can't tell the difference between right and wrong. A sociopath knows the difference - he just doesn't care.
    2. Re:Not even 0.5kilowatts.. by Anonymous Coward · · Score: 2, Informative

      Well, yeah. Most HAMs don't have dish antennae with diameters measurable in friggin miles...

    3. Re:Not even 0.5kilowatts.. by jandrese · · Score: 4, Informative

      On the other hand, it's not like your average HAM has the Deep Space Network at his disposal. 70m antennas are bigger that you might expect.

      --

      I read the internet for the articles.
    4. Re:Not even 0.5kilowatts.. by CausticPuppy · · Score: 4, Informative

      Yeah but it's directional signal coming from the probe. 0.5 kilowatts of narrow-beam signal goes a lot farther than 10 kilowatts broadcasted from an omnidirectional antenna. But you need dishes at both ends, and they have to be aligned correctly.

      I'm sure I'm not using the correct terminology (in case HAM radio experts are reading this) but that is the gist of it.

      --
      -CausticPuppy "Of all the people I know, you're certainly one of them." -Somebody I don't know
    5. Re:Not even 0.5kilowatts.. by nyrk · · Score: 2, Informative

      for transmitting from millions of miles away and some HAMs are using 10 kilowatts upwards just for transmitting earth-to-earth!

      Some, but it is considered very bad form to use more power than necessary. Transmitting across the ground is very different than transmitting through the space. Line of sight drastically reduces the ammount of power you need, as well as using directional antenas.

    6. Re:Not even 0.5kilowatts.. by Anonymous Coward · · Score: 0

      10KW? Doesn't sound like a very responsible ham.

    7. Re:Not even 0.5kilowatts.. by strictnein · · Score: 1

      70m antennas [nasa.gov] are bigger that you might expect.

      Damn. That is bigger than I thought it would be. One question though. Where's the headphone jack to listen for pulsating alien transmissions?

    8. Re:Not even 0.5kilowatts.. by Slinky+Saves+the+Wor · · Score: 1

      But that's a big ass dish and DSP gear they're using to catch the signals from Cassini...

      --
      I do not moderate.
    9. Re:Not even 0.5kilowatts.. by mschiller · · Score: 2, Informative
      I should hope NO U.S. Ham is using 10 Kilowatts since we are limited to 1.5 KW output power. Now we won't talk about the Effective Radiated Power, due to the gain of the antenna's used.

      1. http://web.wt.net/~w5un/mba2003.jpg
    10. Re:Not even 0.5kilowatts.. by mschiller · · Score: 1

      Opps wrong button... That Antenna array I can assure you has much much more then 10 Kilowatts ERP.

      -- Matthew Schiller, A.R.S. KD6BWE

    11. Re:Not even 0.5kilowatts.. by Auntie+Virus · · Score: 2, Funny

      I started building one, but the friggin neighbors complained again...

      --
      Why yes, I *AM* new here. Why?
    12. Re:Not even 0.5kilowatts.. by Tenebrious1 · · Score: 5, Funny

      70m antennas are bigger that you might expect.

      What, like 75 meters?


      --
      -- If god wanted me to have a sig, he'd have given me a sense of humor.
    13. Re:Not even 0.5kilowatts.. by Anonymous Coward · · Score: 0

      They must be buffed.

      Oh, wait, the SWG forum is over there...

    14. Re:Not even 0.5kilowatts.. by adeyadey · · Score: 1

      If I recall, the transmitter on Voyager-2 only has 20 watts of power available as it heads towards the heliopause, well beyond Pluto. Its RTG have degenerated over 30 years. The Deep Space Network has to pick up and decode that signal from a distance of around 100 AU..

      --
      "You lied to me! There is a Swansea!"
    15. Re:Not even 0.5kilowatts.. by Chanc_Gorkon · · Score: 1

      Hams (HAM IS NOT A ACRONYM!) aren't even authorized to use 10 KW. The legal limit is 2 KW I believe. Even so, you don't even need that much power. It's also in the test that hams aare authorized to use 2KW on some bands, but are technically bound to use only the least amount of power to establish communications. Most type accepted rigs are capable of 100 to 200 W PEP. QRP hams have been known to use any where form 500 mW to 5 W and are able to communicate world wide with radios like Yaesu's FT-817 and Icom's IC-703. Ham's also use directional antennas as well. Some use dishes, but most use a Yagi or Log Periodic. Yagi's can also be stacked so as to increase directional gain(not really feasible for HF bands, but definitely in the VHF and UHF Bands). A good antenna is more important then power with anything and I bet NASA uses GREAT antennas!

      --

      Gorkman

    16. Re:Not even 0.5kilowatts.. by Chanc_Gorkon · · Score: 1

      Not necesarily....but odds are they are using a Dish antenna. Dishes are directional. So that 500 Watts looks much bigger. Is pumping 10 KW into a omni going to get you the range that 500 W pumped into a dish? I don't know. Too many variables to calculate...you have near field losses, feed line losses, SWR losses (almost impossible to get exactly 1:1 SWR) and other unknowns would make it difficult to predict the actual amount of power coming out. Predicting range is like guessing. Considering you'd have to account for atmospheric conditons, conditions in the magnetosphere, Solar Flares, cosmic radiation...etc etc. If your like NASA, you probably know all of this, but most ham's don't really have an idea of how far a specific radio/amplifier/antenna combo would go. We just go off of experience. We generally after a while get pretty good at judging when we need to increase power or check the antenna. Most hams know with their current mobile setup when they hit X part of town, they need more power then when elsewhere to hit the repeater.

      --

      Gorkman

  4. Victory of SCIENCE over ECOIDIOLOGY by vi+(editor) · · Score: 3, Interesting

    Remember when Greenpeace and other eco-idiologists wanted to abort the Hygens-Cassini mission due to the Plutonium batteries because they might drop back on earth and contain TEH EVIL RADIOACTIVE PLUTONIUM which would kill seals and cute little children ?
    Lucky the officials at NASA and ESA weren't that stupid and fought off this attack.
    The tremendous success of this mission illustrates how these 21th century idiologists are could stiffle science and cause harm for the whole world.
    It makes me wonder if we could get this done today or in year with the eco rising to power in Europe and perhaps US after the elections, too.

    1. Re:Victory of SCIENCE over ECOIDIOLOGY by Anonymous Coward · · Score: 0, Flamebait

      Naturally, you share the same concern with respect to biosciences and Xian (among others) fundamentalism. Right?

      In which case, it is odd that you are so concerned about the post-election scene. There's plenty to be outraged about right now.

    2. Re:Victory of SCIENCE over ECOIDIOLOGY by Anonymous Coward · · Score: 0, Flamebait
      The tremendous success of this mission illustrates how these 21th century idiologists are could stiffle science and cause harm for the whole world.

      As opposed to the current administration which bases its scientific thought process on religion rather than empirical evidence, right?

    3. Re:Victory of SCIENCE over ECOIDIOLOGY by EvilTwinSkippy · · Score: 5, Insightful
      Airborne plutonium dust is nothing to sniff at. Plutonium is harmless as a solid, but in dust form it's very toxic. Of course, so are the vapors from the rocket's propellent tanks, just about every combusted plastic and rubber compound on the spacecraft, and all the vaporized metal.

      Yes, the greenies were making a mountain out of a molehill. Nuclear powered satellites have been launched for years, and the reactors are specifically designed to survive the destruction of the spacecraft.

      The problem is that we live in a world that is only willing to offer 30 seconds of attention about any subject at a time.

      --
      "Learning is not compulsory... neither is survival."
      --Dr.W.Edwards Deming
    4. Re:Victory of SCIENCE over ECOIDIOLOGY by strictnein · · Score: 3, Insightful

      The far left bases their decisions and opinions on just as much "science" as the far right does. To the far left, nature and humanity is god. To the far right, God is god.

      Take your pick.

    5. Re:Victory of SCIENCE over ECOIDIOLOGY by Mz6 · · Score: 4, Funny
      "The problem is that we live in a world that is only willing to offer 30 seconds of attention about any subject at a time."

      What are you talking about? It's not like the entire World has ADD or some... Hey, what's that shiny thing over there?

      --
      Hmmm.
    6. Re:Victory of SCIENCE over ECOIDIOLOGY by dtolman · · Score: 1

      But to be fair, would breathing in the fumes from a melting Cassini kill you any quicker than breathing in the fumes from a melting computer or a melting car?

    7. Re:Victory of SCIENCE over ECOIDIOLOGY by EvilTwinSkippy · · Score: 1

      Well if the fumes didn't get you, the deep freeze or asphyphiation in the vacuum of space would for sure.

      --
      "Learning is not compulsory... neither is survival."
      --Dr.W.Edwards Deming
    8. Re:Victory of SCIENCE over ECOIDIOLOGY by dtolman · · Score: 1
      Vacuum of space? It was a vacuum - until you threw your melting spacecraft garbage there! Now its only a near-vacuum with Plutonium dust! Damn you NASA!!! You've ruined the last untouched region of the universe.

      Where do we have to go now to enjoy a nice clean refreshing vacuum?

    9. Re:Victory of SCIENCE over ECOIDIOLOGY by EvilTwinSkippy · · Score: 3, Funny
      Where do we have to go now to enjoy a nice clean refreshing vacuum?

      I dunno, the appliance section of [insert retail store]?

      --
      "Learning is not compulsory... neither is survival."
      --Dr.W.Edwards Deming
    10. Re:Victory of SCIENCE over ECOIDIOLOGY by joehoya · · Score: 5, Informative

      Lots of people are saying that Cassini uses a nuclear reactor... this is not the case as Cassini actually uses 3 Radioisotope Thermoelectric Generators (RTG). RTGs are different from reactors in that they are much simpler devices which produce electricity directly from the decay of radioactive material, in this case PU-238. Reactors on the other hand produce power from heat generated by a controlled nuclear chain-reaction.

    11. Re:Victory of SCIENCE over ECOIDIOLOGY by Anonymous Coward · · Score: 0

      The tremendous success of this mission illustrates how these 21th century idiologists are could stiffle science and cause harm for the whole world.
      It makes me wonder if we could get this done today or in year with the eco rising to power in Europe and perhaps US after the elections, too.


      Kinda like when Congress Cut funding for the Super Collider.

    12. Re:Victory of SCIENCE over ECOIDIOLOGY by Anonymous Coward · · Score: 0

      Ash-shadu anna laa ilaha il Allah.

    13. Re:Victory of SCIENCE over ECOIDIOLOGY by Rei · · Score: 1

      ...This is your last chance. After this there is no turning back. You take the blue pill, the story ends and we go back to play-bite death-matching. You take the red pill, and I tell you the truth about... Hey! Kiki?!?! NO! Zoe, she ate BOTH pills!

      --
      I'm an owl exterminator!
    14. Re:Victory of SCIENCE over ECOIDIOLOGY by EvilTwinSkippy · · Score: 1
      Ok. That's like saying a wristwatch is not a chronomiter because it isn't mounted to the bridge of a ship.

      If it ticks like a clock, and keeps time like a clock, it's a clock. If it harnesses energy from the decay of nuclear elements, and it does so by converting heat to electricity, it's a Nuclear reactor.

      --
      "Learning is not compulsory... neither is survival."
      --Dr.W.Edwards Deming
    15. Re:Victory of SCIENCE over ECOIDIOLOGY by Anonymous Coward · · Score: 0

      I still think that to the far left G-d is G-d, but they feel a "social responsibility" to take care of nature and humanity. And to the far right G-d is G-d, but no human shall stand in their way.

    16. Re:Victory of SCIENCE over ECOIDIOLOGY by greg_barton · · Score: 1

      To the far left, nature and humanity is god. To the far right, God is god.

      Take your pick.


      I pick neither.

    17. Re:Victory of SCIENCE over ECOIDIOLOGY by Rasta+Prefect · · Score: 3, Informative
      If it ticks like a clock, and keeps time like a clock, it's a clock. If it harnesses energy from the decay of nuclear elements, and it does so by converting heat to electricity, it's a Nuclear reactor.

      There are some very significant differences. A Nuclear reactor involves an induced chain reaction. This is just harnessing energy from passive decay. RTG's last a lot longer, but produce less power.

      --
      Why?
    18. Re:Victory of SCIENCE over ECOIDIOLOGY by Surt · · Score: 1

      Of course, your ability to post about this success came about as a result of your non dying when a potentially fatal accident didn't happen. Had the accident occurred and killed you, we wouldn't have to listen to your disdain of the ecologists.

      Just because you get lucky doesn't mean risk doesn't exist.

      --
      "Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
    19. Re:Victory of SCIENCE over ECOIDIOLOGY by ch-chuck · · Score: 0, Offtopic

      I pick neither.

      Yeah, like here in the middle, where I am God.

      --
      try { do() || do_not(); } catch (JediException err) { yoda(err); }
    20. Re:Victory of SCIENCE over ECOIDIOLOGY by red+floyd · · Score: 1

      "If you choose not to decide, you still have made a choice" -- Rush

      --
      The only reason we have the rights we have is that people just like us died to gain those rights. -- Cheerio Boy
    21. Re:Victory of SCIENCE over ECOIDIOLOGY by aelbric · · Score: 1

      Of course, just because there's risk doesn't mean you won't get lucky.

      The greatest chance of scientific stagnation is if we forego all risk. Given enough risk mitigation, I'll "light the fuse" and you can go hide. No one lives forever.

      --
      nos laetus epulor qui would domito nos
    22. Re:Victory of SCIENCE over ECOIDIOLOGY by Surt · · Score: 1

      That's absolutely true. Science should be restrained by a reasonable risks/reward ratio.

      Science that risks millions of lives should require much more stringent investigation, consideration and deliberation, while science which risks basically no lives can go on unimpeded.

      Cassini may have risked millions of lives. No one knows with much confidence just how dangerous it would have been if the worst had happened. Reasonable scientists felt the risk of mass deaths was not negligible. A great deal more investigation could have been done at a reasonable price before that risk was taken.

      --
      "Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
    23. Re:Victory of SCIENCE over ECOIDIOLOGY by Anonymous Coward · · Score: 0
      The problem is that we live in a world that is only willing to offer 30 seconds of attention about any subject at a time.
      Wanna go ride bikes?
    24. Re:Victory of SCIENCE over ECOIDIOLOGY by node+3 · · Score: 1

      Remember when Greenpeace and other eco-idiologists wanted to abort the Hygens-Cassini mission due to the Plutonium batteries because they might drop back on earth and contain TEH EVIL RADIOACTIVE PLUTONIUM which would kill seals and cute little children ?

      Most of those who were against the launch did expect the mission to succeed without deploying plutonium in the atmosphere. Their complaint was that the odds that it *could* fail catastrophically were unacceptably high. These odds were increased by the fact that the Cassini-Huygens craft was also to make a close fly-by of the Earth on its journey as a means of gaining speed.

      Now we're dealing with two times when failure could kill thousands of people.

      Given that rockets fail, and probes crash into planets, their concern is something that *must* be addressed. NASA has already spread plutonium though the atmosphere due to failure, so this isn't theoretical (if somehow you think that only non-radioactive payloads fail in the atmosphere).

      Given enough attempts, there will be an accident. When that happens, will taunting and pretending that you aren't driven by ideology (by claiming you are "SCIENCE" and they are "ECOIDEOLOGY") make things OK? Will you just shrug it off and say, "Huh. Well, accidents happen!" then oppose attempts at investigations into what went wrong and what the effects were?

    25. Re:Victory of SCIENCE over ECOIDIOLOGY by adeyadey · · Score: 1

      Plutonium is evil down here on earth, but in space it is the only way to fuel a mission like this, at this time at least.

      The point is that, here on earth, there is now a wealth of clean energy options available, it just needs the will to exploit themm..

      --
      "You lied to me! There is a Swansea!"
    26. Re:Victory of SCIENCE over ECOIDIOLOGY by Anonymous Coward · · Score: 0

      Airborne plutonium dust is nothing to sniff at.

      So to speak.

    27. Re:Victory of SCIENCE over ECOIDIOLOGY by DeanAsh · · Score: 1
      A device that harnesses energy from nuclear decay is a nuclear reactor? Fine. Then a device that harnesses energy from nuclear fusion is also a nuclear reactor.

      Like, um, trees.

      --
      What is the shortest sig that cannot be expressed in fewer than 20 words?
    28. Re:Victory of SCIENCE over ECOIDIOLOGY by meringuoid · · Score: 1
      Now we're dealing with two times when failure could kill thousands of people.

      That, at least, is true. If something goes horribly wrong at launch then in a worst-case scenario the range officer can't destroy the rocket and a huge amount of metal and highly explosive fuel crashes into Miami. If the flyby goes badly wrong then the spaceprobe could strike the Earth at interplanetary velocity, and if ground zero happened to be a city then that, too, could kill thousands.

      Not sure what all that has to do with the radioactives, though.

      --
      Real Daleks don't climb stairs - they level the building.
  5. Moon landings and technology by Anonymous Coward · · Score: 0

    I can imagine in 10-15 years time -

    "when they went inside Saturns orbit, they only had the same technology as your wristwatch does"

    Except it will be a pda, mobile, write chronometer, tv, flashlight.

    *checks*

    Camera.

  6. Horses? by birdwax2k · · Score: 2, Funny

    ...this mission has plenty enough horses to run the stretch with plenty-o-pep to spare.

    Lets hope none of them are named Smarty Jones...

  7. a little over half a horse by missing000 · · Score: 1, Funny
    1. Re:a little over half a horse by Anonymous Coward · · Score: 0

      They wanted to have horse-chariot races arond the rings of Saturn, but all they could manage to bring was half a horse. I just hope it's not the half that breathes.

  8. Slashdot NASA Early by EvilTwinSkippy · · Score: 2, Funny

    Beat the rush.

    --
    "Learning is not compulsory... neither is survival."
    --Dr.W.Edwards Deming
  9. I Wonder... by grunt107 · · Score: 5, Funny

    Do the rings make the same noise represented on the Star Trek Voyager intro?

    1. Re:I Wonder... by ebh · · Score: 3, Funny

      I suspect it's a few clanking and crunching sounds followed by static...

  10. After this insertion... by teamhasnoi · · Score: 5, Funny
    on to Uranus!


    Here, I'll help you out.

    -1, Troll.

  11. sounds? by rgf71 · · Score: 2, Funny

    I'd much rather hear the sounds of Saturn than the sounds of Uranus.

    Sorry. Had to do it.

    1. Re:sounds? by Anonymous Coward · · Score: 0

      come on mods... The obligatory fart joke CAN'T be marked as redundant!

      made me laugh anyway...

    2. Re:sounds? by Rei · · Score: 1

      It's sad to see how immature some of the people here are. I thought you were supposed to outgrow toilet humor by age 8....

      --
      I'm an owl exterminator!
    3. Re:sounds? by Anonymous Coward · · Score: 0

      I'm not even 1 yet, you insensitive clod!

      (on Saturn, anyway).

    4. Re:sounds? by Anonymous Coward · · Score: 0

      Outgrowing toilet humour is not something that I believe anyone can honestly say they can achieve...

      There are fart jokes everywhere and if you laugh at just one of them (and you will, if you're human) then they're worth while.

      $0.02

  12. Insertion Imminent by Timesprout · · Score: 4, Funny

    Alas the only other time geeks encounter this situation is when they plug in a new video card.

    --
    Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
    What truth?
    There is no dupe
    1. Re:Insertion Imminent by EvilTwinSkippy · · Score: 1

      Speak for yourself. I have the kid to prove otherwise.

      --
      "Learning is not compulsory... neither is survival."
      --Dr.W.Edwards Deming
    2. Re:Insertion Imminent by TopShelf · · Score: 0, Redundant

      At least the insertion isn't into Uranus...

      Sorry, couldn't help myself there.

      --
      Stop by my site where I write about ERP systems & more
    3. Re:Insertion Imminent by Anonymous Coward · · Score: 0

      Speak for yourself. I have the kid to prove otherwise.

      So, your wife/girlfriend/mother/sister had sex with someone?

    4. Re:Insertion Imminent by Cyberhwk · · Score: 1

      Dang I got all excited about insertion being imminent and all and then I find out its in uranus. Do you realize what a buzz kill that is? I feel like taking a shower now. So dirty. So wrong.

    5. Re:Insertion Imminent by Smidge204 · · Score: 1

      ...you mean a baby goat, right? I mean, you can't just walk into a store and buy a child. I suppose you could kidnap one or buy one off the black market, but that's quite illegal!

      =Smidge=

    6. Re:Insertion Imminent by Anonymous Coward · · Score: 0

      When will life imitate Futurama and rename that planet to stop all of these stupid jokes?

    7. Re:Insertion Imminent by Fishstick · · Score: 2, Funny

      Scientists renamed Uranus in 2024 in order to finally stop all those stupid jokes...

      what did they name it?

      Urectum!</farnsworth>

      --

      There is much cruelty in the universe, John.
      Yeah, we seem to have the tour map.

    8. Re:Insertion Imminent by swillden · · Score: 1

      Speak for yourself. I have the kid to prove otherwise.

      She knows they're hers, you only think they're yours.

      --
      Note to ACs: I usually delete AC replies without reading them. If you want to talk to me, log in.
  13. Religion? by Anonymous Coward · · Score: 0

    The neocon scientific thought process is also based upon maintaining political power and aiding (and abetting) friends in high places. Sometimes a mumbling about free markets will help in coming to terms with technological progress.

  14. Sounds from Saturn? by IGnatius+T+Foobar · · Score: 4, Funny

    Hearing sounds from Saturn is nothing new. My 1997 SL1 (like most old Saturns) is VERY noisy ... you can hear it coming from a mile away. Step on the gas and it sounds like the power steering pump is going to pop through the hood.

    --
    Tired of FB/Google censorship? Visit UNCENSORED!
    1. Re:Sounds from Saturn? by Anonymous Coward · · Score: 0

      Damn, if I had mod points I would have modded that up;)

    2. Re:Sounds from Saturn? by Anonymous Coward · · Score: 0

      Sounds from Saturn almost sound like sounds from Earth. LOL
      How long till they make a techno song out of that Super Psycho Sexy Saturn Static for that ass?

  15. I hope it takes photos by WormholeFiend · · Score: 2, Interesting

    I want to see photos of the rings from inside (the rim? the gap?)...

    BTW, how thick are the rings at the point where the probe is passing through them? How long will it take to clear that space?

    1. Re:I hope it takes photos by Mz6 · · Score: 3, Informative

      I can't answer for the thickness of the rings, but it was mentioned in a few of the articles that NASA is trying to stay as far away from the rings as possible. The closest approach will be from above the rings and the rest of the photographs will be taken from the top of the rings. Other than that, they consider them a collision hazard...

      --
      Hmmm.
    2. Re:I hope it takes photos by WormholeFiend · · Score: 1

      yea but isnt the probe supposed to fly through a gap in the rings? it'd be great to get a photo taken "at level".

    3. Re:I hope it takes photos by CausticPuppy · · Score: 2, Informative

      yea but isnt the probe supposed to fly through a gap in the rings? it'd be great to get a photo taken "at level".

      It is flying through a visible gap, and it's an area that seems to be clear of debris according to all the analysis done so far. But it could just be that the debris is so sparse that it's not visible.
      The entry point is actually well outside the visible rings, but there is another very faint ring (G ring) even farther out.

      NASA realized this during the design phase, which is why they are rotating the spacecraft around so that the dish of its high gain antenna will provide some protection against small rocks while it passes through the ring plane. Seems like if the high gain antenna is damaged, then they have other problems though! I'm thinking it was designed with this purpose in mind, at least for protection against particles under a certain size.

      --
      -CausticPuppy "Of all the people I know, you're certainly one of them." -Somebody I don't know
    4. Re:I hope it takes photos by WormholeFiend · · Score: 1

      are you suggesting that the photos are taken with the antenna?

    5. Re:I hope it takes photos by Naito · · Score: 1

      Actually, for the orbital insertion manuver, Cassini is actually going to be flying THROUGH the rings, I think they're going through the Cassini division, one of the larger "gaps" in the ring system.

    6. Re:I hope it takes photos by CausticPuppy · · Score: 1

      are you suggesting that the photos are taken with the antenna?

      No, and I don't see how you read that in my post.
      The images are transmitted back to earth via the antenna, so hopefully the antenna itself won't be damaged during the ring plane crossing.

      --
      -CausticPuppy "Of all the people I know, you're certainly one of them." -Somebody I don't know
    7. Re:I hope it takes photos by Naito · · Score: 1

      Cassini will be going about as fast as it's ever gone in it's entire trip when it's going through the rings. I doubt it's cameras can track the rings at that speed.

      The rings are only a couple km thick at most, it'll be through in less than a second since Cassini will be travelling at about 20,000km/h at the time.

    8. Re:I hope it takes photos by Anonymous Coward · · Score: 0

      Cassini passes through the F and G rings. F is about 30 miles wide and 87,100 miles from Saturn. G is 300 to 3000 miles wide and is 105,740 miles from Saturn. This works out to a 15,625-mile gap that the s/c has to pass through.

      Numbers are from page 8 of the Cassini-Huygens Saturn Arrival Press Kit June 2004.

    9. Re:I hope it takes photos by meringuoid · · Score: 1
      Seems like if the high gain antenna is damaged, then they have other problems though!

      Oh, come on. There's no way NASA could possibly wreck the high gain antenna on a major planetary probe mission. That's just absurd.

      --
      Real Daleks don't climb stairs - they level the building.
  16. ObSpock by ceswiedler · · Score: 1

    "That is illogical, ensign. Sound cannot travel through the vacuum of space."

    1. Re:ObSpock by Rei · · Score: 4, Informative

      You know, though... when people complain about there being sound in the middle of a big space battle, it always kind of bothers me a bit. Because if you were in space with space ships and missiles blowing up all around you, you *would* hear the sound of explosions as the pressurized gasses and debris from the ship expand in a shock wave travelling at speeds probably quite similar to what we're used to for sound. Sure, it would be all sudden bursts as your spacecraft was hit by the shockwaves, with no prolonged rumbles, but there *would be sound* to a viewer in a spacecraft somewhere.

      And then there's the other things that could possibly cause sound - some of these futurisitic engines are supposed to be powerful ion drives or plasma thrusters, which means that there are very powerful magnetic fields being used and streams of high-velocity charged particles, both of which could possibly have an impact on certain parts of your spacecraft when you get close and make noise. If a beam weapon starts cutting at your ship's hull, your hull is definitely going to make some noise, especially when mechanical components are damaged or gasses start to leak. Etc. There would be lots of sound in a space battle.

      --
      I'm an owl exterminator!
    2. Re:ObSpock by earthforce_1 · · Score: 2, Insightful

      You would hear sounds inside the spacecraft for sure - in fact, one of the biggest complaints about life on the ISS is noise from all the equipment that is operating, it is very difficult to sleep through all the fans, pumps, and various apparatus turning on and off 24/7.

      But from outside, you wouldn't hear anything, unless electrical interference from the ship's system or natural sources was being picked up by your space suit radio. What is interesting, is that astronouts can communicate without radios if they touch their helmets together, as the helmet itself will carry sound.

      Even a nuclear blast in space wouldn't produce much of anything in the way of sound, as the only "atmosphere" would come from the vaporized bomb itself, and would be quite tenuous unless you were right beside it, when the thing went off. And you would of course be vaporized long before you could sense it.

      Most of the explosion effects would be thermal energy and radiation pressure. Particle and directed energy weapons (lasers or phasers?) would not produce any sound at all.

      The only way to get any sound at all floating about in a space battle, is perhaps if you were right beside a ship was ripped apart and lost pressurization. Then you would (very briefly) have a tenuous atmosphere to carry whispers of the ship's destruction. You might have better luck hearing something if you press your helmet to the hull of a vessel.

      --
      My rights don't need management.
    3. Re:ObSpock by Rei · · Score: 1

      Any blast in space will have a blast wave. I personally can't say how concentrated the extremity of the blast wave is, but if you have a 1000kg bomb, and 80% of the gas is within 10cm of the "wave" itself (a rather wide wave), then even from 100 meters away, that's .8 grams per cubic meter when the wave hits. While that's a lot thinner than air at sea level (1.29 kg/m^3), it's moving at several thousand miles an hour - it'll impact you like a hammer. Unlike an explosion on earth, the blast wave isn't being resisted by an atmosphere, and thus will be able to do the sort of damage that on earth only occurs in a relatively small radius, notably further away. And that makes noise. :)

      --
      I'm an owl exterminator!
  17. Sound in space? by Anonymous Coward · · Score: 2, Interesting

    How did they get sound? There is no sound in space (since it requires a medium like the air)... My guess is that the frequency of these "sounds" is close to that of the radiation being measured... Does anyone have the complete information on this?

    1. Re:Sound in space? by Anonymous Coward · · Score: 0

      I believe the idea is that they will be within the atmosphere, where there will be a medium for sound to propagate thru...

    2. Re:Sound in space? by lockefire · · Score: 3, Informative

      The Huygens probe will be recording the sounds of Titan (which has an atmosphere).

    3. Re:Sound in space? by Vireo · · Score: 2, Informative

      Simply reading the related article tells us that Cassini records the radio emission from the interaction between charged particles and Saturn's magnetic field (in order to measure its rotation rate). These radio waves are in the range of 50 to 500 kHz. The 100-300 kHz band was shifted to the audible 0-3 kHz band to produce the sounds.

  18. This is from NASA's page by Anonymous Coward · · Score: 3, Informative

    The rings of Saturn have puzzled astronomers ever since they were discovered by Galileo in 1610, during the first telescopic observations of the night sky. The puzzles have only increased since Voyagers 1 and 2 imaged the ring system extensively in 1980 and 1981. In addition to the images, several Voyager instruments observed occultations of the ring system with radial resolution as fine as 100 meters. The rings have been given letter names in the order of their discovery. The main rings are, working outward from the planet, known as C, B, and A. The Cassini Division is the largest gap in the rings and separates Rings B and A. In addition a number of fainter rings have been discovered more recently. The D Ring is exceedingly faint and closest to the planet. The F Ring is a narrow feature just outside the A Ring. Beyond that are two far fainter rings named G and E. The particles in Saturn's rings are composed primarily of water ice and range from microns to meters in size. The rings show a tremendous amount of structure on all scales; some of this structure is related to gravitational perturbations by Saturn's many moons, but much of it remains unexplained.
    linky

    1. Re:This is from NASA's page by amliebsch · · Score: 1

      You forgot about the O Ring. I hear NASA is trying to cover it up.

      --
      If you don't know where you are going, you will wind up somewhere else.
  19. Pheobe as a source of ice by bcrowell · · Score: 4, Interesting

    People theorizing about asteroid mining in the past had talked about complicated ways of getting ice out of the rare ice-bearing asteroids. Now that we know Phoebe is icy, I wonder if it ends up being the most practical place in the solar system to get ice. Although it's in the outer solar system, which is inconvenient, that's not necessarily such a big deal with solar-powered ion drive propulsion (as demonstrated by NASA already), which theoretically allows you to send anything into any orbit without paying for energy.

    1. Re:Pheobe as a source of ice by EvilTwinSkippy · · Score: 2, Insightful

      Solar power doesn't provide a lot of energy in deep space. The sun out that far look like a really bright star. That why Cassini needed a nuclear reactor.

      --
      "Learning is not compulsory... neither is survival."
      --Dr.W.Edwards Deming
    2. Re:Pheobe as a source of ice by TheLetterPsy · · Score: 1

      How about a link to (as demonstrated by NASA already)?

    3. Re:Pheobe as a source of ice by Neil+Watson · · Score: 4, Informative

      Cassini does NOT use a nuclear reactor. It uses Radioisotope Thermoelectric Generators. Please do no feed misinformation to the nuclear ignorant torch burning masses.

    4. Re:Pheobe as a source of ice by EvilTwinSkippy · · Score: 1

      Let's see, it harnesses power from the decay of heavy elements into lighter ones. What part of Radioisotope did I fail to understand properly?

      --
      "Learning is not compulsory... neither is survival."
      --Dr.W.Edwards Deming
    5. Re:Pheobe as a source of ice by Neil+Watson · · Score: 1

      When you say reactor the unwashed masses assume you mean fission.

    6. Re:Pheobe as a source of ice by EvilTwinSkippy · · Score: 1
      Err, fission is still going on. Fission is the process of a large isotope splitting into smaller more stable isotopes.

      Granted, it's a much slower and cooler process than you would find at a commercial nuclear plant, or in the belly of a ship, but it is the same process.

      --
      "Learning is not compulsory... neither is survival."
      --Dr.W.Edwards Deming
    7. Re:Pheobe as a source of ice by bcrowell · · Score: 2, Informative
      Solar power doesn't provide a lot of energy in deep space.
      Solar-powered ion drives don't require a lot of power; they use low thrust over long periods of time. Check out this link for an example. Note that the name of the craft is "Deep Space 1." It went to the asteroid belt, but even if it went out as far as the orbit of Saturn, it would just have to operate at lower thrust.

      That why Cassini needed a nuclear reactor.
      Cassini doesn't have a nuclear reactor, it has a radioactive source that provides energy by passive heating. (A reactor uses a chain reaction.)

    8. Re:Pheobe as a source of ice by Neil+Watson · · Score: 2, Insightful
      Radioisotope Thermoelectric Generators convert the heat of naturally decaying nuclear material directly into electricity.

      Fission reactors typically control a chain reaction and use the heat to create steam that turns a generator. That generator produces the electricity.

      Yes, at an atomic level the processes are similar (or even the same) but it is important to note the differences. The word nuclear is often maligned due to lack of understanding.

    9. Re:Pheobe as a source of ice by bcrowell · · Score: 1

      "Reactor" is the word you failed to understand properly.

    10. Re:Pheobe as a source of ice by EvilTwinSkippy · · Score: 1

      ... And Evil Twin Skippy was enlightened

      --
      "Learning is not compulsory... neither is survival."
      --Dr.W.Edwards Deming
    11. Re:Pheobe as a source of ice by Idarubicin · · Score: 3, Informative
      People theorizing about asteroid mining in the past had talked about complicated ways of getting ice out of the rare ice-bearing asteroids. Now that we know Phoebe is icy, I wonder if it ends up being the most practical place in the solar system to get ice.

      A variant of this idea was explored by Isaac Asimov way back in the novella, The Martian Way (Galaxy Science Fiction, November 1952; subsequently republished in several collections).

      The characters in the novel propose capturing chunks of ice from Saturn's ring system. We don't need to grab a whole moon--there are cubic-mile-sized chunks of ice in the rings. They might be a bit more manageable to manoeuvre. There are lots to choose from, too.

      --
      ~Idarubicin
    12. Re:Pheobe as a source of ice by corngrower · · Score: 1
      I wonder if it ends up being the most practical place in the solar system to get ice.


      Na, just go down to your local grocery store. They should have some.

    13. Re:Pheobe as a source of ice by ckaminski · · Score: 1

      A reactor, by definition, reacts to something, in this case, the impact of one neutron against another and a cascading effect of atoms splitting. It does not necessarily imply a sustained reaction.

      In which case, an RTG is indeed a reactor, although nowhere near as energetic as the ones run by Exelon, for example. Naturally decaying radioactive material can cause a chain reaction, although it's almost never long-lived since the material density is almost never great enough to sustain it.

      Ask the poor fool who died at Los Alamos in the 40's because he let two plutonium pit halves touch each other.

      It's a semantic difference really... is all I'm saying.

    14. Re:Pheobe as a source of ice by Junior+J.+Junior+III · · Score: 1

      Phoebe is not the most practical place in the solar system to get ice. My refrigerator is.

      "Phoebe! Can you bring me some ice please?"

      "Get it yourself!" /me walks over to refrigerator and extracts ice cubes.

      See?

      --
      You see? You see? Your stupid minds! Stupid! Stupid!
    15. Re:Pheobe as a source of ice by Anonymous Coward · · Score: 0

      Ask the poor fool who died at Los Alamos in the 40's because he let two plutonium pit halves touch each other

      Wikipedia:
      Careless handling of a 6.2 kg plutonium sphere resulted in a lethal dose of radiation at Los Alamos on August 21, 1945. Harry Daghlian received a dose estimated to be 510 rems, he died four weeks later. Another death occurred in 1958 at the Los Alamos uranium enrichment plant. Plutonium accumulated inside a mixing vessel. A new batch was transferred and all 8 kg of plutonium came together in the vessel's center. A worker exposed to the radiation died less than two days later.

    16. Re:Pheobe as a source of ice by GedConk · · Score: 1

      Wouln't taking ice from Europa make more sense ? After all Jupiter is much closer to us than Saturn is.
      Of course, if they do find life there, the question becomes more complicated, but otherwise, it looks like an excellent water reserve to me ;)

    17. Re:Pheobe as a source of ice by bcrowell · · Score: 1

      If you're willing to land in a deep gravity well and then lift your cargo back out of it, there are plenty of possibilities, including Mars and Earth.

    18. Re:Pheobe as a source of ice by bcrowell · · Score: 1
      Ah, good point! The only thing in Phoebe's favor might be that it orbits a lot farther out from Saturn, so it would take less energy to lift the ice out of Saturn's gravity well, but then, I guess the whole premise was that propulsion was cheap. This link does seem to imply that the rings are dense enough to pose a real hazard to navigation, though.

      We don't need to grab a whole moon
      I was just talking about digging ice out of it, not moving the whole moon.

    19. Re:Pheobe as a source of ice by Waffle+Iron · · Score: 1
      Fission is the process of a large isotope splitting into smaller more stable isotopes.

      Actually, the term "fission" is usually reserved for a large isotope splitting into two roughly equal-sized atoms. The term "decay" usually refers to an isotope splitting into a small particle (electron, photon, or helium nucleus) and a new isotope of slightly smaller size. RTGs collect energy from the decay of a particular rare plutonium isotope (this is not the same isotope of plutonium used for fission in nuclear bombs).

      Decay usually occurs at a fixed rate that depends only on the isotope in question, and is not affected by outside factors. Fission is most commonly encountered in chain reactions whose rate is highly dependent on the physical configuration of the fuel, and may highly unstable (like a bomb). The job of a nuclear reactor is to use complex thermally controlled geometry and/or mechanical means to keep the fission reaction rate stable. OTOH, since decay is perfectly stable by itself, an RTG just sits there. It has no moving parts.

      Genuine nuclear reactors have been used in space, especially by the Soviet Union. Several dozen Soviet fission reactor cores from defunct military satellites are still orbiting the earth today.

  20. Ah, but did it generate the 450? by DumbSwede · · Score: 4, Insightful
    450 may not sound like a lot, until you have to generate it for yourself years on end.

    Your little computer is a lot bigger if you include the size of the Power Station it is attached to through a long peice of wire.

    Someone should calculate how the amount of coal or oil that would be needed to provide power for Cassini if it weren't nuclear. Or the size of solar cells needed at that distance from the sun (and their wieight).

    1. Re:Ah, but did it generate the 450? by Fouquet · · Score: 1

      Or the size of solar cells needed at that distance from the sun (and their wieight).

      NASA did just this. See the PDF I linked to above, and there is a diagram showing the relative sizes solar arrays would have to be to be used at the outer planets.

    2. Re:Ah, but did it generate the 450? by EvilTwinSkippy · · Score: 4, Informative
      That's pretty easy to do. Look up the enthalpy of combustion for fuel oil and coal. Any good thermodynamic textbook will have both. The unit for enthalpy is KJ/g (Kilojoules per gram of fuel.) A watt is 1 joule per second. (Isn't metric lovely?)

      I googled around and found some stats from the power industry as "energy density of fossil fuel"

      Energy density of Fuel Oil: 42.5 MJ/Kg
      Energy density of Anthracite Coal: 31.4 MJ/Kg

      MJ/Kg is Mega (million) joules per Kilogram. Our power unit provides 450 watts, thus uses 0.00045 MJ/s. A day's worth of power is 0.00045 MJ/s 3600 s/hour * 24 hours/day = 38.9 MJ. (Remember your signifigant digits!)

      To convert that back to weight:
      38.9 MJ/Kg / 42.5 MJ = 0.915 Kg/day of Oil
      38.9 MJ/Kg / 31.4 MJ = 1.23 Kg/day of Coal

      We are in the 7th year of the flight, so:

      0.915 Kg/day * 365.26 days/year * 7 years = 2340 Kg of Oil
      1.23 Kg/day * 365.26 * 7 = 3150 Kg of Coal.

      Plus or minus.

      --
      "Learning is not compulsory... neither is survival."
      --Dr.W.Edwards Deming
    3. Re:Ah, but did it generate the 450? by Rei · · Score: 5, Informative

      I'll do it for gasoline. :)

      Let's assume that Cassini averages needing 700 watts over the course of its lifetime, and lets assume a lifetime of 18 years. That's about 80 MWh of power. Assuming a 40% efficiency diesel engine burning gasoline and oxygen (have to take the O2 with you!)...

      Gasoline has an energy density of 45.8 MJ/kg. Since 2 molecule of gasoline requires about 25 molecules oxygen (O2) to react, you have a molar ratio of 1 mole gasoline to 12.5 moles oxygen. 1 mole of gasoline mass about 114 grams; 12.5 moles of o2 mass about 400 grams. So, your overall energy density is about 10.2 MJ/kg.

      Since we're burning at 40% efficiency, that's about 4.1MJ of energy per kg fuel/oxidizer. 1 joule = 0.0002778 Wh. 4.1MJ/kg = 1.1kWh/kg. 80MWh / 1.1kWh/kg = ~73 metric tons.

      33 kilograms of plutonium suddenly sounds quite appealing, ne? :)

      --
      I'm an owl exterminator!
    4. Re:Ah, but did it generate the 450? by EvilTwinSkippy · · Score: 4, Informative
      Oh yeah, and double all those amounts. That is the theoretical maximum that could be derived from the fuel. In practice, the best we can achieve is 40 percent. (In an industrial setting, small vehicle's like cars are lucky to get 10%).

      So

      2340 Kg / 0.40 = 5850 Kj of oil
      3150 Kg / 0.40 = 7880 Kj of coal

      --
      "Learning is not compulsory... neither is survival."
      --Dr.W.Edwards Deming
    5. Re:Ah, but did it generate the 450? by vlm · · Score: 2, Insightful

      And, you forgot the weight of they oxygen you'd need to carry in order to burn the carbon.

      --
      "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
    6. Re:Ah, but did it generate the 450? by GuyFawkes · · Score: 1

      You forgot the weight of the oxygen to burn the fuel, there is none in space.........

      --
      http://slashdot.org/~GuyFawkes/journal
    7. Re:Ah, but did it generate the 450? by EvilTwinSkippy · · Score: 1

      Well, I also forgot to bring along the boiler, coolent water, heat exchanger, turbine, plumbing, ash disposal mechanism, spare parts...

      --
      "Learning is not compulsory... neither is survival."
      --Dr.W.Edwards Deming
    8. Re:Ah, but did it generate the 450? by Limburgher · · Score: 1

      Don't forget the mass of the oxygen to allow for combustion to obtain the energy. I would think that quantity would be non-trivial.

      --

      You are not the customer.

    9. Re:Ah, but did it generate the 450? by Idarubicin · · Score: 2, Interesting
      Oh yeah, and double all those amounts. That is the theoretical maximum that could be derived from the fuel. In practice, the best we can achieve is 40 percent.

      Are you sure? That's pretty close to true on earth, where the cold side of a Carnot cycle is going to be at around 300 K. Space, however, is mostly a nice, big, cold blackbody at around 3 kelvin or so (cosmic microwave background.) That should help quite a bit.

      On the other hand, other posters have noted that the mass calculation neglects the oxidizer that would have to be carried. That works out to being three or so times the mass of the fuel, depending on the specific hydrocarbons chosen.

      --
      ~Idarubicin
    10. Re:Ah, but did it generate the 450? by adeyadey · · Score: 1

      >0.915 Kg/day * 365.26 days/year * 7 years = 2340 Kg of Oil

      And of course you will have to carry your own Oxygen too.

      At this distance, nuclear does seem to be the only option, be it RTG as used here, or the reactors being considered for JIMO..

      --
      "You lied to me! There is a Swansea!"
  21. Sound? What sound? by allanj · · Score: 4, Informative

    The sound they refer to is a frequency-shifted and time-compressed recording of emissions from charged particles in the magnetic field around Saturn. There is no actual "sound" there, as sound requires an athmosphere(sp?) of some sort. There's athmosphere a-plenty on Saturn (most of it IS probably gas, after all), but none near or around the probe.

    --
    Black holes are where God divided by zero
    1. Re:Sound? What sound? by Watcher · · Score: 1

      Later on we'll hopefully hear sound from the surface of Titan, once the Huygens probe lands. That could be interesting (or it could just be the sound of blowing wind).

    2. Re:Sound? What sound? by Anonymous Coward · · Score: 0

      When the Huygens probe lands in the main square of a Titanian city, we could learn the Titanian translation of "WTF!!!"

  22. Power? What power? by eugeni · · Score: 1

    ...Well, this power may be enough for all this electronics, but it is not quite enough to power a single Nvidia card... :-)

  23. The Song of Saturn At Last! by MooseByte · · Score: 2, Funny

    "Thanks to all that power, and the plethora of electronics on Cassini and the Huygens probe, we can now hear sounds from Saturn."

    Not to mention that giant space phonograph needle they included at the last minute. Now we just have to have it doesn't skip on the Cassini Division.

    (Append witty RIAA reference here.)

  24. Nah, they did it two days early by Limburgher · · Score: 3, Funny

    They figured if they entered orbit two days before the scheduled date, they could avoid attacks by the Saturni insurgents.

    --

    You are not the customer.

  25. absolutely by khallow · · Score: 1

    I guess it depends on the application, but I don't see solar working further out than Jupiter, and really you should be much closer (say Mars or Earth). Incidentally, I've run across multiple definitions of "deep space" from 2,000,000 km to an region "outside" the solar system. Very far from the Sun seems a good definition as any. :-)

  26. Choice: Saturn or Spacewalk by CompressedAir · · Score: 4, Informative

    Today marks an interesting first (at least as far as I have been able to tell): the NASA channel has had to choose which current space activity to put on TV.

    On Wednesday there will be an EVA on the ISS right around the time the Cassini stuff will be happening. Thus, NASA TV had to choose, for the first time, which thing happening in space was more exciting.

    How cool is that? There's actually enough going on up there that one TV channel is not enough!

    Whadya know, the revolution IS televised.

  27. Cassini-Huygens Saturn Orbit Insertion Imminent by Chuck+Bucket · · Score: 1

    ...yeah, that's what you think!

    CB

  28. Saturn by garbs · · Score: 0, Offtopic

    Sounds Boring

  29. Only 20 Watts... by Jott42 · · Score: 4, Interesting

    The travelling-wave amplifier gives only 20 Watts of output power, which feeds into a 4 meter dish antenna. At 8.4 GHz this gives a gain of about 50 dB. EIRP then at 2 MW. (And a free space loss to Saturnus of about 300 dB....)

  30. Let the orbital insertion begin... by Titchener · · Score: 4, Funny

    wakka-chikka-wakka-chikka "Hello Saturn, I'm Cassini-Huygens. I'm here to repair your plumbing."

    1. Re:Let the orbital insertion begin... by identity0 · · Score: 1

      Saturn: Roman god of the harvest
      Cassini: Family of astronomers, great-grandpa Giovanni(1625-1712), grandpa Jacques(1677-1756), daddy Cesar-Francois(1714-1784), and son Dominique(1748-1845).
      Huygens: Dutch physicist(1625-1695)

      No thanks, I don't think I want to watch that one.

  31. Hey, those sounds... by NeoGeo64 · · Score: 1

    Hey that sound from Saturn sure sounds familiar. Sounds like the last mp3 I tried to download off KaZaA. Planet Saturn should sue the RIAA for using it's sound.

  32. Insertion by Anonymous Coward · · Score: 0

    I can't wait for us to send a spacecraft to Uranus and say we have orbital insertion at Uranus.

  33. Re:I can't wait... by perdu · · Score: 1
    To each their own, but I prefer the sound of Venutian insertion.

    --
    You only use 2% of your DNA
  34. The real reason for the mission by fedork · · Score: 2, Funny

    we all know that _real_ reason for this mission is to deliver a piece of metal to an alien stuck on Titan.

    --
    ...remember good 'ol times when IP used to mean Internet Protocol....
    1. Re:The real reason for the mission by Paulrothrock · · Score: 1

      Am I missing something? What's this a reference to?

      --
      I'm in the hole of the broadband donut.
  35. MOD PARENT UP, +1 INSIGHTFUL by Anonymous Coward · · Score: 0
  36. It's a good thing... by Anonymous Coward · · Score: 0

    Think about it this way... at least the insertion isn't into the orbit of Uranus :)

  37. Huhhuhu....He said insertion by Jackal82277 · · Score: 1

    How can you not read an article that has the word "insertion" in it 3 times in the summary. Not to mention the word plethora thrown in there for giggles. I think that the summary in it self makes this article a candidate for the Hall of Fame.

  38. Solar cell sums by Anonymous Coward · · Score: 0

    Saturn is (on average) 9.5 times further away from the sun than the earth => the intensity of sunlight there is 9.5 squared = 90 times less.

    Solar intensity around the earth is approx 1kW per metre squared.

    I take the efficency of solar cells as 20% (this is a pretty impressive figure for Earth satellites, but prob. it's easier to run the panels cold - and therefore more efficiently - out at saturn. Anyway it'll do for now).

    Mass-wise 20 W/kg is not an atypical performance figure for solar panels (at the Earth). At Saturn this would become 0.2 W/kg.

    So Cassini would need about 200 m2 of cells, with about 2 tonnes total panel mass.

  39. Give us a break! by Anonymous Coward · · Score: 0

    I know how to find Canada: start at the United States, go north. I'd love to remember simple instructions for other planets, too, but the damn things keep moving...

  40. Re:Adrian! by Anonymous Coward · · Score: 0

    It's a shame that you aren't able to comprehend these words. It is especially interesting to me that you likely feel superior to Bush, despite the fact that you obviously have substituted bitterness for intelligence in your own life. Don't worry about it too much, though, it's a common liberal mistake.

    The question posed in this oft-repeated troll post does not present mutually exclusive alternatives...

  41. ROFLMAO!!!! by Anonymous Coward · · Score: 0

    WTFOMG!!1 You are teh funny, man!

  42. Shorter Slashdot... by Anonymous Coward · · Score: 3, Insightful

    133 comments posted so far. Here's a summary.

    7 off-topic "troll" posts.

    30 posts regarding the nuclear decay powering the craft or simply clarifying the fact that it is not a nuclear reactor.

    96 comments making jokes about the use of the word "insertion" with more than 80 of those comments also mentioning Uranus.

  43. I was an intern at JPL... by IronChef · · Score: 4, Interesting

    Long ago, when I thought I wanted to be an EE, I did a couple of summer internships at JPL. I worked on the Cassini flight computer. My coworkers, especially the lead ASIC designer, were blisteringly smart people. If Cassini fails, it won't be the computer design at least!

    Back then, the project was called "CRAF/Cassini" where CRAF was "Comet Rendezvous/Asteroid Flyby." CRAF was supposed to be the sister ship to Cassini, but it was cut for budgetary reasons. Too bad... with all the design work done how much could it have cost to just build another ship?

    See, we were building this neat computer that would be reused on the next generation of probes, instead of having custom computer hardware for each... but of course it didn't work out that way.

    I was lucky enough to see Cassini (and Galileo) in the Vehicle Assembly Facility. There was an observation deck where you could watch the guys in the clean room building the spacecraft. It was very cool to look down and realize, "that is going to Saturn." Or wherever.

    Cassini is the last of the old school probe designs... a gigantic and expensive. She'll give us a heck of a show.

  44. You forgot... by ckaminski · · Score: 1

    the screaming. And the dying. Those make noise too. At least while your compartment is still pressurized.

  45. Actually, many Hams get by fine just a few watts by MooseByte · · Score: 3, Interesting

    "some HAMs are using 10 kilowatts upwards just for transmitting earth-to-earth!"

    Actually, ignoring the 1.5KW max Ham radio ops are legally bound to, most Ham operators operate in the 100 watt range (in the HF freqs == "shortwave"), and there's a dedicated core of low-power enthusiasts who communicate around the world on 5 watts, 1 watt or even a few hundred milliwatts. (The microwatt crew even come out during favorable solar conditions).

    Check out these guys for a starting point.

    It varies by spectrum of course (VHF/HF/etc.) but I've personally worked every continent with less than 5 watts using just a homemade wire antenna, no fancy NSA-like array of metal high in the air.

    Antarctica was the most fun - Russian op down there at their research station. Darn neatstuff!

  46. The reason by Anonymous Coward · · Score: 0

    It's summer, most of the children are home from school for vacation, and unfortunately they're hanging out here and on Xbox Live.

  47. You have fogotten... by Anonymous Coward · · Score: 0
    the screaming. And the dying. Those make noise too. At least while your compartment is still pressurized.

    In space, nobody can hear you scream.
  48. Re:I can't wait... by GedConk · · Score: 2, Funny

    Talking about Venus, I heard she's HOT ! ;)

  49. Cassini's Real Interaction with the Rings by Rhodnius · · Score: 4, Interesting

    In a nutshell, here's how Cassini will interact with the rings during the orbital insertion.

    Saturn right now is tilted, so that the south/"bottom" side of its rings is facing towards the Sun and Earth. Hence, Cassini is approaching Saturn from "underneath" as we see it from Earth. The orbit insertion requires Cassini to pass through the equatorial/ring plane south-to-north as it approaches the planet. It will fire its rocket while on the north side of the rings, and then coast back to the south side on its way back out.

    Now, how is Cassini doing that safely? It's doing so by going through the ring plane where there are no rings. It could be thought of as a "gap", but Cassini really isn't anywhere near the rings when it crosses them. The crossing points are far outside the main mass of the ring system.

    A rough analogy is this. Suppose you lived in Alaska, and had a sailboat named Cassini. Now suppose you had to sail from Alaska to Mexico without bumping into anything. Naturally, you'd pass between Hawaii and the continental US. That's a rough analogue to what's going on at Saturn - the main mass of the rings is like the continental US landmass (and there's a few small intra-ring gaps like the Mississippi River), while there's a few small outside rings sort of like the Hawaiian islands.

    Would it be possible that your sailboat bumped into a rock or debris or something that we didn't know was there? Yes. Is that possibility remote enough that it makes for the safest course to your destination? Also yes.

    1. Re:Cassini's Real Interaction with the Rings by WormholeFiend · · Score: 1

      so, your sailboat can't actually take photos of Hawaii while it's at the same latitude? (to use your own analogy)

    2. Re:Cassini's Real Interaction with the Rings by Teancum · · Score: 1

      I think the analogy is more like trying to sail between Oahu and Midway, but yeah, there still is a pretty big gap of ocean there.

      Check out this webpage to get further details. It is going to travel between the "F" and "G" rings, which are pretty faint by themselves. There will be a larger likely hood of running into something in that region of space, probabaly an order of magnitude higher than would normally be found within the Saturnian system of moons, but still fairly low.

    3. Re:Cassini's Real Interaction with the Rings by Rhodnius · · Score: 1

      The analogy holds. Your sailboat could take photos of Hawaii, but you wouldn't see much. You'd only see the front edge of an island, with a beach and one layer of trees or buildings. Compare this to an aerial view that would show everything.

      So it is with Saturn; you need to be outside the rings looking at the entire expanse to really see them. From within the rings, you really wouldn't see much.

    4. Re:Cassini's Real Interaction with the Rings by WormholeFiend · · Score: 1

      I still think it'd be interesting to see, as this point of view is not likely to be available to any camera anytime soon after.

      Especially if the probe takes photos at level and at angular increments from the plane of the rings.

  50. Pronunciation by galore · · Score: 1

    Wondering how to pronounce Christiaan Huygens' name? You're in luck: http://frank.harvard.edu/~paulh/misc/huygens.htm

    Unfortunately, if you were raised in America, it's probably impossible for you :)

  51. "Horses?" by LMariachi · · Score: 1
    More like 3/5ths of a horse.

    (1 hp=745.7 watts)

  52. In space... by PTDC · · Score: 1

    ...no one can hear you stream.

  53. the reference... by drewness · · Score: 1

    Sirens of Titan by Kurt Vonnegut

  54. sound in space by boldra · · Score: 1

    I'm perfectly happy to accept sound in movie space battles because it seems a logical part of a the spacecraft's UI.

    Humans can roughly identify locations of objects by sound without looking at them. Any good UI will make use of sound to supplement visual information. Therefore it seems logical that the highly advanced computers on board a spaceship would be capable of simulating sound from other sensor data, in exactly same way that many astronomy photos have invisible spectra shifted into visible.

    It just seems obvious that a pilot who could tell the difference from a particle weapon and a rocket without looking would have a combat advantage. The same would go for telling the difference between a Romulan and a Klingon spaceship. Why waste a very advanced part of our brains by sitting in a completely silent cockpit?

    Furthermore, I expect the cockpits of the future to provide an environment very similar to what we see in movies or computer games, because that's what we expect! The cockpits will probably even be quite similar and standard in design, unless some marketing arsehole screws around with them.

    --
    I've been posting on the net since 1994 and I still haven't come up with a good sig!
  55. Re:I can't wait... by troon · · Score: 1

    You joke, but a microphone has sent back data from the surface of Venus. Sound levels only, rather than actual sound, but hey, at 90 bar and 450 deg C, that's not too shabby.

    See near the end of this page.

    --
    Ydco co ,df C erb-y go. a Ekrpat t.fxrapev