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Space Science

Cassini-Huygens Reaches Orbit Around Saturn 251

Mick Ohrberg writes "The probe Cassini-Huygens is now officially in orbit around Saturn. Last nights' retro-burn was completed according to plan, down to the second, which in and of itself is an amazing feat, considering all data received is 1h24m old, as well as 900 million miles away. I must say, it was fairly exciting to watch the webcast, and see the signal fade behind the A-ring, and all but disappear behind the B-ring - all in (somewhat delayed) real-time. The SOI (Saturn Orbit Insertion) also saw Cassini-Huygens whisk by Saturn at around 68,000 mph at an altitude of about 12,000 miles from the cloud tops - the closest to the gas giant the probe will ever be during its planned 4-year mission, for instance the much awaited Huygens mission to Titan."
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Cassini-Huygens Reaches Orbit Around Saturn

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  • Pictures. (Score:5, Informative)

    by Mz6 ( 741941 ) * on Thursday July 01, 2004 @10:24AM (#9581090) Journal
    Not sure when the article was written but there are already raw and press images released [slashdot.org] as well as some others [nasa.gov]. The quality isn't as good as some may think and it really doens't show much detail into the rings at all.
    • by rfinnvik ( 16122 ) on Thursday July 01, 2004 @10:53AM (#9581396)
      http://saturn.jpl.nasa.gov/spacecraft/instruments- cassini-iss.cfm

      "Cassini's higher-resolution camera is able to see a penny, 1.5 cm (0.5 in) across, from a distance of nearly 4 km (2.5 mi)."

      Sounds like the cameras has some potential, at least :)

      Oh, and NASA, as always, rock at converting metric to imperial... :P

      1.5 cm = 0.59 in
      4 km = 2.48 miles
    • Does anyone who knows a thing or two about CCD's know why these preliminary unprocessed [nasa.gov] images are so badly banded (horizontally)?
      • Re:Pictures. (Score:4, Informative)

        by weyoun6 ( 793168 ) on Thursday July 01, 2004 @12:09PM (#9582485)
        Its the camera's electrical interference - they havent removed the bars and all the specks from cosmic rays.
        • Umm.... (Score:4, Informative)

          by jmichaelg ( 148257 ) on Thursday July 01, 2004 @12:51PM (#9583020) Journal
          Cosmic rays create randomly oriented streaks. Noise induced specks have a random "snow-like" appearance. The bands appear to be some sort of malfunction in the imaging circuitry.

          This image [nasa.gov] shows all three imaging problems. There appears to be a short cosmic ray streak in the lower left quadrant veering about 30 degrees downward and to the right, there may be some speckle in the black band or it may be a real signal (the white dots in the black band) and there's banding throughout the entire image that spreads from the white regions to the black and back to the white.

          • by Anonymous Coward
            What is that horizontal waviness in the picture?

            There is a low level source of noise in the camera's signal as it comes out of the sensor and gets converted to numbers. This noise adds and subtracts a small amount to the signal in a cycle. When the data is put into an image, one can see it as bright and dark bands in the image. The amount of noise is very small and is not noticeable in most images. Images that are of black sky or very dark can show this noise. The camera records the baseline of the signa
      • CCDs read out a row of pixels at a time; any interference upstage from the sampling elements shows up as horizontal banding...
    • Re:Pictures. (Score:4, Informative)

      by CheshireCatCO ( 185193 ) on Thursday July 01, 2004 @12:06PM (#9582422) Homepage

      You can also find pictures at the CICLOPS [arizona.edu] site.

  • wiki (Score:5, Informative)

    by Nspace13 ( 654963 ) on Thursday July 01, 2004 @10:29AM (#9581130) Homepage
    wikipedia has a great bit of information [wikipedia.org] on the history of this project including a section called "Plutonium power source and controversy".
    • I read an article that called for "No Plutonium in Space!". I hate to rain on their parade, but there's plenty of it out there already... Cue tinfoil hats.
    • Re:wiki (Score:5, Funny)

      by Jugalator ( 259273 ) on Thursday July 01, 2004 @10:35AM (#9581207) Journal
      "Plutonium power source and controversy".

      Yeah, it's horrible how many Saturnians it might kill while in duty. :-P
    • Wouldn't the plutonium canisters survive re-entry? I remember watching something on Mr. Wizard years ago showing plutonium casings subjected to severe abuse and coming out without a scratch.
      • They probably would, but even in a worst-case scenario I doubt there would have been any deaths at all. I really have no idea where Kaku got his numbers from, but it is certainly not from anything that's been through IAEA... The 120 deaths quoted by NASA is pretty easy to see how they came up with. Besides, many studies today suggest that there isn't a very harmful effect of exposure to just a little radiation. I was really surprised it was an issue at all.
  • typo title (Score:5, Interesting)

    by bluethundr ( 562578 ) * on Thursday July 01, 2004 @10:30AM (#9581135) Homepage Journal
    The NAME, I say I say the NAME, son is Christiaan Huygens [st-and.ac.uk]. Associate of the Protestant Defender [wikipedia.org] and natural philosopher [amazon.com].
    • Christiaan Huygens (Score:5, Interesting)

      by rastakid ( 648791 ) on Thursday July 01, 2004 @10:40AM (#9581266) Homepage Journal
      Just like Huygens I'm Dutch, and thus I was taught a lot about him in school during the physics hours.
      The biggest thing Huygens brought the physica is the 'Huygens source'. A simplified explanation: A Huygens source starts sending out sound (air vibration) because the source itself got vibrated by another source. So, a Huygens source doesn't 'create' sound, but simply relays it.

      Of course this is really simplified and in reality it's fairly more complex.
    • Re:typo title (Score:3, Informative)

      by onion2k ( 203094 )
      The "Cassini" bit is named after Giovanni Domenico Cassini, a famous maths bloke.

      http://www-gap.dcs.st-and.ac.uk/~history/Mathema ti cians/Cassini.html
  • by rastakid ( 648791 ) on Thursday July 01, 2004 @10:31AM (#9581156) Homepage Journal
    considering all data received is 1h24m old

    And we bitch when our CounterStrike match lags 300ms?!
  • Closest? (Score:3, Funny)

    by Grayswan ( 260299 ) <willNO@SPAMgrayswan.com> on Thursday July 01, 2004 @10:33AM (#9581184) Journal
    Won't it be closer when its orbit finally decays to 0?
    • My thought exactly (Score:3, Informative)

      by RetiredMidn ( 441788 ) *
      Although somebody has pointed out that they did qualify it as the closest approach during the 4-year planned mission, note that Galileo [nasa.gov] survived 6 years beyond its 2-year planned orbital mission, and sent back data even as they intentionally crashed it into Jupiter to keep if from possibly contaminating one of Jupiter's moons in the future. I wouldn't be surprised if a similar fate is in store for Cassini-Huygens: both a significantly extended mission, followed by a controlled "disposal" when its usefulnes
  • by kyknos.org ( 643709 ) on Thursday July 01, 2004 @10:33AM (#9581185) Homepage
    nice image showing gravitonal waves in the ringshttp://spaceflightnow.com/cassini/images/0407 01rings1.jpg
  • by kyknos.org ( 643709 ) on Thursday July 01, 2004 @10:36AM (#9581210) Homepage
    "It feels awfully good to be in orbit around the lord of the rings," said Charles Elachi, director of the Jet Propulsion Laboratory. "It's going to be a huge leap in our understanding of the Saturnian system.""This has just been an incredible ride," he said. "This wasn't NASA going into orbit around Saturn, it's the Earth going into orbit around Saturn because 17 countries made this happen. This is the way exploration should be done: by the Earth."

    if only we could do more things like this
  • Try and imagine... (Score:4, Insightful)

    by cOdEgUru ( 181536 ) on Thursday July 01, 2004 @10:37AM (#9581228) Homepage Journal
    Try and imagine this small piece of machine, an artificial eye, open to the wonders of our solar system, falling through the infinite depths of space, so that we can forget for a moment, all the troubles and tribulations around us, the cold steel and the raging fire and look beyond the physical confines of what makes us human and gaze in awe at this small contraption carrying a message of hope, of peace, of our thirst for knowledge in a never ending journey towards everything that is unknown.
  • by Jugalator ( 259273 ) on Thursday July 01, 2004 @10:37AM (#9581234) Journal
    It would be interesting to see how it looked like meanwhile it was in the ring system?

    Or when it was nearby enough to see the massive amounts of rocks inside.

    Or didn't it pass through the actual rings?
    • by confused one ( 671304 ) on Thursday July 01, 2004 @10:58AM (#9581441)
      they did; but, the scientists mentioned something about how fast they were traveling: (I'll quote some from the spaceflightnow article)

      "The photo sequence began around 12:30 a.m., 18 minutes or so after Cassini finished a 96-minute rocket firing to brake into orbit around Saturn. Streaking just above the rings at speeds greater than 50,000 mph, Cassini's narrow-angle camera took a series of snapshots, opening its shutter for just five milliseconds per picture to avoid blurring. Each picture was separated from those on either side by about 600 miles because of Cassini's extreme velocity."

      "It takes us about a minute to take a picture and so in the time we shutter the exposure, read out the camera and get ready to take a picture again, we have crossed a thousand kilometers."

      They never had a chance to get a close up of the debris in the rings. In fact, it would take a significant effort, timing it just right, to do so; and, they would risking damage by exposing the camera lens to any dust in the path. If you remember, they were turning Cassini so the big dish pointed in the direction of travel to act as a shield against any small objects in their path, as they crossed the rings.

    • Passing through rings is not a dangerous thing. The reason being is that the dust that makes up the rings literally has kilometers of empty space between chunks. So much so that the chances of passing through the rings and hitting something are miniscule.
    • ...they passed through the ring plane, in the huge gap between the F and G rings.

      Passing through the rings themselves would likely have been disastrous.
  • by techmuse ( 160085 ) on Thursday July 01, 2004 @10:54AM (#9581407)
    considering all data received is 1h24m old, as well as 900 million miles away Recieving old data is easy. Receiving data that is 900 million miles away is very hard. The spacecraft is 900 million miles away. The data must be here, or we could not have received it. ;)
  • by carn1fex ( 613593 ) on Thursday July 01, 2004 @10:56AM (#9581426)
    You know its really easy to take for granted the fact that in the last 50 years we have gone from a confined world to launching interplanetary probes billions of miles away. I think we are all a little desensitized from watching too much star trek/star wars and setting our expectations way too high. It really struck me this weekend when i was sitting on the beach with my girlfriend, relaxing and said "the cassini probe is going into orbit around saturn this week." She just smiled, because shes not that geeky, but really, never have humans ever been able to say something like that in matter-of-fact conversation. Now its the norm. Hooray for us:)
    • Sending out probes doesn't make you space-faring any more than throwing a message in a bottle into the ocean makes you seafaring. It is, however, an important intermediate step, and one that does (and should) fill us with awe as we consider the scale of what we are hoping to do.

      Then, we should get up off our collective asses, and do it.

  • Good for us (Score:5, Insightful)

    by scoser ( 780371 ) on Thursday July 01, 2004 @11:03AM (#9581483) Journal
    This is a great day for science and I'm glad that we didn't give into the protesters [animatedsoftware.com] back in 1997 (to prevent the mission) and 1999 (to stop Cassini from flying past Earth on its way back to Saturn after a gravity slingshot around Venus).
    • Speaking of protesters, these people [animatedsoftware.com] wanted NASA to "stop Cassini" after it developed some reaction wheel glitch at Jupiter by crashing it into the giant planet.

      Does anyone have an info as to whether this issue (the reaction wheel, not the asshat suggestion) was resolved?

  • I heard Carlos [trb.com]'s comment on KTLA 5 [trb.com]'s morning news today. It was quite funny!
  • by The_REAL_DZA ( 731082 ) on Thursday July 01, 2004 @11:33AM (#9581912)
    Yes, I realize I should know this one already, but I can't seem to recall ever hearing his name actually said out loud and it aggravates me that I mentally stumble through every instance of his name in print.
  • by peter303 ( 12292 ) on Thursday July 01, 2004 @11:40AM (#9582022)
    Most of our planet names come from the Latin form. Sometimes I see the Greek name used as the adjective. In this case it would be "Chronus", even more awkward.
  • Waves in the Rings? (Score:3, Interesting)

    by S_Dub ( 739327 ) on Thursday July 01, 2004 @01:38PM (#9583543)
    Can anyone explain the seemingly horizontal waves that are running through all of the rings? They seem to be fairly uniform and direction and size. However, the orientation does not seem to be radial from the planet itself or any other object... Any conjecture out there as to what has caused this? They almost seem like an artifact in the images themselves.

    Also, is anyone else a little disappointed that these are the best images we're going to get of the rings or are there going to be better pictures in the future? This is the closest the spacecraft is going to get to the rings, yet I really was hoping to see the individual components of the rings themselves. I've seen the intro to Voyager, and I wanted to see tumbling boulders...
  • by peter303 ( 12292 ) on Thursday July 01, 2004 @02:01PM (#9583839)
    Is Cassini the last of the billion-dollar deep-space probes? I don't see much else funded. Theres and on-again, off-again flyby to Pluto next decade. The Mercury probe Messenger was axed in the current White House budget. The next four launch-cycles to Mars are being worked on. But these are relatively inexpensive, small things in the couple hundred million range. Maybe a few more lunar and comet missions in the works too.
    The previous NASA administrator Goldin promoted the faster-cheaper-smaller (and less reliable) probe model. I guess the initial Hubble troubles and the decade-long Galileo & Cassini projects spooked him out. At least Cassini will last for 4 to 10 years.

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