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Space Science

Cassini Probe Does Titan Flyby 115

Posted by michael
from the wave-for-the-camera dept.
EccentricAnomaly writes "Today, Cassini had its first close encounter with Titan around 8:30AM PDT. Data from the flyby will start coming down around 6:30PM PDT, and you can watch the pictures live on NASA TV. If you want higher resolution or just to stare at one picture for a while, the raw images will be put on the web right away, with pretty press images to follow the next day. And if you want to know about the observations planned for the flyby, you can read this PDF or watch this animation."
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Cassini Probe Does Titan Flyby

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  • by fembots (753724) on Tuesday October 26, 2004 @05:41PM (#10636232) Homepage
    From NASA's faq - "Cassini stores the gathered information on two Solid State Recorders (SSR) with a combined capacity of 4 gigabits, about the volume of a compact disk (500MB)."

    It seems scientists are pretty confident that they can unload much data during Cassini's 9 hours downlink session.

    Imagine if there were some downtimes when earth communication cannot be established for a couple of days...
    • Yeah, the next probes sent to space really should use microdrives for backup at least. I mean, put an IPod on a probe and not only will the probe be able to store tens of GBs of data, but it could even play MP3s on a simulated speaker through the entire mission. Besides, if a probe finds a representative of an intelligent race out there, it could use its IPod to swap music.

      • Bad idea. (Score:4, Funny)

        by Anonymous Coward on Tuesday October 26, 2004 @06:03PM (#10636473)
        What would the aliens think if they get a peace offering of music, only to get sued by RIAA shortly thereafter?
      • by Tablizer (95088) on Tuesday October 26, 2004 @08:46PM (#10637755) Journal
        Yeah, the next probes sent to space really should use microdrives for backup at least. I mean, put an IPod on a probe and not only will the probe be able to store tens of GBs of data, but it could even play MP3s on a simulated speaker through the entire mission. Besides, if a probe finds a representative of an intelligent race out there, it could use its IPod to swap music.

        This is why NASA does not hire 14-year-olds.
      • by Anonymous Coward
        You clearly don't know anything about electronics/systems that operate in space. IPods would quickly broke because:
        1. Temperatures ranging from -200 C to 300 C (at least)
        2. Sound pressure and shaking during a launch
        3. Malfunctioning of electronics caused by cosmic rays and solar wind
        Additionally, every gram which NASA sends to the orbit costs a LOT of cash. Materials/design of IPod would weight too much and take too much space.
    • by Macphisto (62181) on Tuesday October 26, 2004 @05:58PM (#10636416) Journal
      Imagine if there were some downtimes when earth communication cannot be established for a couple of days...

      Good Lord, man! What in blazes are you planning?

    • by Anonymous Coward
      Bill G. said: "4Gbit Solid State Recorders should be enough for everybody."
    • by badfrog (45310) on Tuesday October 26, 2004 @06:07PM (#10636514)
      Interference has always been a huge factor, the Space Shuttle still used iron-core memory in its systems in the late 80s, because it wasn't affected by radiation. Can't just pop in some SDRAM and expect it to work out there.
    • by HunahpuMonkey (613489) on Tuesday October 26, 2004 @06:10PM (#10636543)
      > From NASA's faq - "Cassini stores the gathered information on two Solid State Recorders (SSR)
      > with a combined capacity of 4 gigabits, about the volume of a compact disk (500MB)."
      >
      > It seems scientists are pretty confident that they can unload much data during Cassini's 9 hours
      > downlink session.
      >
      > Imagine if there were some downtimes when earth communication cannot be established
      > for a couple of days...

      According to CNN [cnn.com] that very problem exists. The buffers in those recorders are in danger of writing over the data before it can sucessfully be sent to Earth.

      "The flyby of Titan was expected to go smoothly in space, but bad weather on Earth could affect Cassini's transmissions to the Deep Space Network, scientists said.

      Cassini has only one chance to send data back to Earth before it is overwritten with data from its next set of observations, scientists said."
      • With all the orbiting equipment we've shot up there over the years, why not a powerful radio antenna, with huge memory storage.

        It doesn't have to go very far from earth's surface, so the fuel costs will be lower than sending rad-shielded hard drives to saturn.
    • It seems scientists are pretty confident that they can unload much data during Cassini's 9 hours downlink session.

      Imagine if there were some downtimes when earth communication cannot be established for a couple of days...

      What would more storage buy you? It wouldn't increase the downlink bandwidth, and there's only so much time available to transfer it down, so you'd just get further and further behind. Losing downlink time means losing data, period.

      Telemetry bandwidth is always an issue; instruments alw

      • by Rei (128717) on Tuesday October 26, 2004 @06:46PM (#10636857) Homepage
        Not *always*. When Cassini isn't doing an encounter, it's sitting around doing pretty much nothing (regular bits of telemetry data, random readings, occasional snaps of Saturn or distant shots of moons, etc). Greater storage space, even if not accompanied by an increased bandwidth improvement, allow you to gather more data from your insturments during flybys, which you can transmit during the less-important inter-flyby periods.
        • by jnik (1733) on Tuesday October 26, 2004 @09:31PM (#10638058)
          When Cassini isn't doing an encounter, it's sitting around doing pretty much nothing

          Hardly true. Now, granted, I don't have the Cassini instrument duty-cycle schedule right here, but I can at least take a quick look at the projected orbit plots. It looks like apicenter is about 60-70 Rs. Frontside magnetopause distance is 20-25 Rs (roughly), the flanks are likely further out, and I'd put money on the tail extending at least 70 Rs. Even on the front side I'm sure there's plenty of science to be done in the sheath, bow shock, and even upstream solar wind.

          So the plasma instruments and magnetometer would be busy for probably half the distance of each orbit. I imagine the cosmic dust analyzer is probably useful the whole time, and the UV cameras (I'm too lazy to compare the resolution to Hubble...). That's a lot of data.

          And it really does come down pretty slow. At 35 kbit/s, that's roughly a day and a half, best case, to empty the recorders, out of approximately two weeks for an orbit (not always being in "view", either, and the DSN sometimes needed for other things...).

          I'm sure somebody would find some use for extra storage if it were there, but the limitation doesn't mean Cassini's spending any great amount of time idle.

          • You *can* fill up the link with whatever you want. But having up-to-the-second telemetry and magnetosphere readings has a much lower priority than getting all of the data you can from a brief but incredibly valuable flyby.
          • So the plasma instruments and magnetometer would be busy for probably half the distance of each orbit. I imagine the cosmic dust analyzer is probably useful the whole time, and the UV cameras (I'm too lazy to compare the resolution to Hubble...). That's a lot of data.

            These measurements aren't data intensive, and they don't fill up the SAR.

            The problem is Titan encounters are followed immdiately by Saturn periapses.... both of which generate lots of data. If you decide to keep Titan data to download a se
    • I can see how you might fit the images, spectra and other data in 500MB of storage but how do they fit the synthetic aperture radar data in there? It must be huge!.....anyone know?
    • Actually, we have a saying: "The rain in Spain falls mainly on DSS-63" The rain is a very large concern for everyone here tonight. We have already requested a backup downlink session tomorrow in case of problems tonite. Basically, we stole a 70 meter antenna from another project. The critical data will make it down at the end of the Madrid pass, as there is dual coverage with a 34 meter Goldstone, CA station. Best of luck.
  • by waynegoode (758645) * on Tuesday October 26, 2004 @05:44PM (#10636266) Homepage
    The links on the webpage open pop-up windows to show the video. You can't right click and save the files. I did a little right-clicking and source viewing and found the URLs of the actual files.
  • 4 Gig recorders (Score:3, Interesting)

    by Baumann (238242) on Tuesday October 26, 2004 @05:47PM (#10636294)
    They have to be confident. If the system goes for N days without contact, I suspect they'll have far greater worries than just overfull download buffers. Say like - why isn't our little lost machine talking to us?
  • What if they spy aliens? Won't that cause a little alarm amongst the general population?
  • Aliens (Score:4, Interesting)

    by Indy Media Watch (823624) on Tuesday October 26, 2004 @05:54PM (#10636370) Homepage
    I understand from the webpage that NASA TV can be received by anyone with a satellite decoder and presumably TV stations to rebroadcast images.

    They include "live mission feeds" and live images that we can see from the Cassini prove.

    Knowing NASA's lineage, is there any form of delay applied to these 'live' feeds? Or could we one day see something which may otherwise be classified (alien waving at the camera, dead astronaut) on the screen in real-time?
    • Re:Aliens (Score:5, Funny)

      by Timesprout (579035) on Tuesday October 26, 2004 @06:22PM (#10636638)
      Well normally when pixar do the special effects for these missions there are no issues. I believe the faking effects for this mission have been outsourced to Bollywood due to budget constraints so please dont be alarmed if the mission actually turns out to be a love story between Cassini and Hygens and several hirsuite men in colourful outfits burst into a song and dance routine halfway through it.
    • Even though the chances are remote, finding undeniable evidence of alien life on Titan will forever change how we look at the universe and how life actually works. Suppose there is something alive on Titan... what is its biochemical makeup? How does it metabolize? Reproduce? If there is something there, it'll be quite unlike anything we've ever encountered.

      It would be interesting to see the general political, scientific, and public reaction here on Earth if the Huygens probe due to be released in Januar
    • "Live" means live from the control room. There isn't any realtime video camera on the Cassini.

      The images come from something like a CCD photocamera optimized for astronomical observation. They are saved on an internal memory buffer and transmitted back several hours or even days later. Even if there's some ET waving at it, Cassini would probably not even see it.
    • Speaking of live satellite video feeds check out the movie Spin [100777.com].
    • Space probes don't send back jpegs or gifs. The images have to be assembled and processed to remove compression artifacts and "hot spots" where an errant gamma ray or ion hit a CCD and caused a big bright spot.

      There will always be a delay between the raw data is recieved through the Deep Space Network and when it will show up on a computer screen at JPL because it has to be properly assembled. Not tin foil (I hate that term...it's actually aluminum foil) hat stuff, just the nature of the game.

  • Here is a link to a CNN story [cnn.com] that also has a nice video animation link of the event.

    Can't wait until Virgin Galactic offers rides out there! :)

  • sci.space.news (Score:5, Informative)

    by noselasd (594905) on Tuesday October 26, 2004 @05:58PM (#10636421)
    Subject: Cassini Image: Eyes on Xanadu
    From: baalke@earthlink.net (Ron)
    Newsgroups: sci.space.news
    Followup-To: sci.space.policy
    Date: 26 Oct 2004 09:25:07 -0700

    http://www.nasa.gov/mission_pages/cassini/multim ed ia/pia06107.html

    Eyes on Xanadu
    October 25, 2004

    Cassini image of Titan, revealing the bright continent-sized terrain
    known as Xanadu

    This image taken on Oct. 24, 2004, reveals Titan's bright
    "continent-sized" terrain known as Xanadu. It was acquired with the
    narrow angle camera on Cassini's imaging science subsystem through a
    spectral filter centered at 938 nanometers, a wavelength region at which
    Titan's surface can be most easily detected. The surface is seen at a
    higher contrast than in previously released imaging science subsystem
    images due to a lower phase angle (Sun-Titan-Cassini angle), which
    minimizes scattering by the haze.

    The image shows details about 10 times smaller than those seen from
    Earth. Surface materials with different brightness properties (or
    albedos) rather than topographic shading are highlighted. The image has
    been calibrated and slightly enhanced for contrast. It will be further
    processed to reduce atmospheric blurring and to optimize mapping of
    surface features. The origin and geography of Xanadu remain mysteries at
    this range. Bright features near the south pole (bottom) are clouds. On
    Oct. 26, Cassini will acquire images of features in the central-left
    portion of this image from a position about 100 times closer.

    The Cassini-Huygens mission is a cooperative project of NASA, the
    European Space Agency and the Italian Space Agency. The Jet Propulsion
    Laboratory, a division of the California Institute of Technology in
    Pasadena, manages the Cassini-Huygens mission for NASA's Science Mission
    Directorate, Washington, D.C. The Cassini orbiter and its two onboard
    cameras were designed, developed and assembled at JPL. The imaging team
    is based at the Space Science Institute, Boulder, Colo.

    For more information about the Cassini-Huygens mission, visit
    http://saturn.jpl.nasa.gov and the
    Cassini imaging team home page, http://ciclops.org

    Credit: NASA/JPL/Space Science Institute

    And

    Cassini-Huygens makes first close approach to Titan

    Today the NASA/ESA/ASI Cassini-Huygens spacecraft makes a fly-by of Saturn's
    largest moon Titan - the closest ever performed.

    Read more:
    http://www.esa.int/SPECIALS/Cassini-Huygens /SEMB2E 0A90E_0.html
  • good flavor (Score:4, Interesting)

    by Striker770S (825292) on Tuesday October 26, 2004 @06:05PM (#10636493) Journal
    it seems that everybody is looking at mars and wondering why are space program is not really doing too much. Its good to show the public the vast and very unique moons of the gas giants. I am looking forward to see if they are going to do a "fly by" on the moon with the completely water frozen surface, orbiting jupiter (or maybe it was saturn). as long as NASA doesnt screw up and place anything backwards or messes up on unit conversions, then they have my support again!
    • Re:good flavor (Score:3, Informative)

      by red floyd (220712)
      n the moon with the completely water frozen surface, orbiting jupiter (or maybe it was saturn)

      Europa, the second Galilean moon (Io, Europa, Ganymede, Callisto).
      • Life on Europa? (Score:2, Informative)

        by CRepetski (824321)
        A flyby of the second Galilean moon could prove to be especially beneficial, as it has some of the most favorable conditions for life (or past life) in our solar system.
        • Not that favourable. Radiation from Jupiter's equivalent of the Van Allen belts gives a dose of about 600 Rem/day on Europa (a certain lethal dose for a human). Admittedly it's a far cry from the 45000Rem/hour a spacecraft would catch orbiting in the middle of the Jovian magnetosphere, and perhaps simple life could handle a few rays.
    • Actually the already are planning it with the JIMO probe-http://www.theregister.co.uk/2004/09/22/jupi ter_probe/ [theregister.co.uk]
    • Re:good flavor (Score:1, Informative)

      by Anonymous Coward
      it seems that everybody is looking at mars and wondering why are space program is not really doing too much

      Nobody's doing too much because the rest of the Solar System is a dead wasteland. If Mars had something to offer, then we'd see all the world's powers scrambling to get first dibs. The best use of resources at this point would be to continue improving new launch/reentry technology and perfecting space stations.
  • The sound of Cassini flying by Titan: :)
  • by jangobongo (812593) on Tuesday October 26, 2004 @06:43PM (#10636830)
    Not only will the Cassini be taking pictures, but its ion and neutral mass spectrometer will "scoop up" and sample Titan's atmosphere as it passes at a distance of 1,200 kilometers (745 miles).

    "One important goal of this flyby is to confirm scientists' model of Titan's atmosphere to prepare for the Huygens probe descent," according to this article at SpaceDaily.com. [spacedaily.com]
  • raw images (Score:4, Informative)

    by Anonymous Coward on Tuesday October 26, 2004 @08:13PM (#10637556)
    The raw images may be higher resolution but guess what....they are also "raw"! That means they haven't been processed yet. The image data isn't very useful unless you have the necessary parameters / algorithms to process the data.

    There will be several steps in processing the image data, bad pixel correction (I guess these CCDs should have very few); white/black balance; tonal / grey calibration; others? I'd be surprised if there weren't a few others.

    I guess the white/black balance is the most important thing I mentioned ....responsiveness accross the CCD won't be the same and must be compensated for. I don't know if they've got a seperate grey calibration step (you'd need calibration data to reproduce it)....you could fiddle with tone curves yourself to make stuff pleasing to the eye / see different stuff.

    Can anyone supply more details on the calibration?

    So far as I know it's not worth downloading the raw images unless you want to exercise some bandwidth....I think that Nasa might give out the calibration data to some people (remember British scientists discovering possible new moon?)....Anyone know all the ins and outs?
    • Re:raw images (Score:3, Informative)

      by H01M35 (801754)
      From the FAQ [nasa.gov]

      Why does the contrast look different between images?

      The camera measures light from an object at each point in an image and assigns it a number from zero to 4095 depending on its brightness. Sometimes the scientist can't afford to send this amount of data for each pixel because of the amount of storage it takes. The camera has the ability to convert this range of values to those from zero to 255. The camera does this according to a preset table of values designed by the scientists. This ta

    • They'll warp this image to to some regular map projection. The motion of the space craft and oblique angle of the camera on some of the shots are corrected for. This particularly noticeable on raw Mars orbitor pics.
  • I want my Goop! (Score:3, Interesting)

    by Tablizer (95088) on Tuesday October 26, 2004 @10:18PM (#10638367) Journal
    This is cool. It is a map pointing out where the lander is targeted [nasa.gov]. The map was made from prior flybys and also shows where today's mission is to image.

    If the dark stuff really is liquid goop, as some speculate, I wish they would target a little to the north to land right in the stuff and float. I would much rather see images from floating on a lake of goop than yet more rocks. We got enough of rocks from Mars, Venus, the moon, and Eros. Time for liguid landings. Please NASA, retarget for the sake of Goop!
    • Re:I want my Goop! (Score:2, Interesting)

      by Tablizer (95088)
      They've done some preliminary image processing. Here is an example [nasa.gov]. Notice the crisp boundaries in the third image. It looks just like a water (liquid) boundary. Dust or rocks rarely have such distinct boundaries of color for this much area. This adds to the hydrocarbon lake theories. This is so cool!

      However, it still means that the probe may land on an oval-shaped island (matching it with the prior map), which would be a bit of a disappointment, as described above. NASA, please target the damned liquid! T
      • Why? THe probe may be designed to float but there is almost certainly more to see on solid surface than a in a homogenous pool of liquid!
        • Why? THe probe may be designed to float but there is almost certainly more to see on solid surface than a in a homogenous pool of liquid!

          I disagree. Rocks are *not* what is special about Titan. There are dozens of other planets and moons with rocks and soil. Been there done that.

          A extraterrestrial ocean would be a fantistic sight, even if it is not exactly postcard-ready. It is a one-of-a-kind.
          • Uhm, have you ever been on a ship in the middle of the ocean? It is a one-of-a-kind sight. In fact, its bloody boring because its the same in ALL directions!
            • Uhm, have you ever been on a ship in the middle of the ocean? It is a one-of-a-kind sight. In fact, its bloody boring because its the same in ALL directions!

              Not if it is the first time you see it on another world. A bunch of rocks get boring after a while also.

              By the way, scientist say that waves on Titan may be huge but slow-moving because of the weaker gravity. I doubt we'll see anything that dramatic from this mission, but there are some incredible possibilities on Titan.
  • by Thaidog (235587) <slashdot753 AT nym DOT hush DOT com> on Tuesday October 26, 2004 @10:20PM (#10638384)
    It's the death star! Red Alert!
    http://saturn.jpl.nasa.gov/cgi-bin/gs2.cgi ?path=.. /multimedia/images/large-moons/images/image17.jpg& type=image
  • There comes a point when I hope that robot spacecraft like this fail and the logical conclusion is that "Well... I guess we will have to send people."

    I am glad that our knowledge is expanding by orders of magnitude, but inwardly I long for a vast open ocean (of space) being the only thing separating us from a "new world" where we can go, colonize, and spread the virus of humanity before we kill ouseleves living in our own filth.

    Naturally it will be a robot that finds this new world first, but there is jus

    • by Anonymous Coward
      There is a plan made up by some NASA engineers called HOPE, which would be a manned mission to Callisto in 2045. Sadly I don't think it will happen, at least not that soon, but one could hope, right? At least it shows that these people are thinking about something more than just moon and mars... even though we don't have permanent settlements on either one, we will, and when we do, it's good to have some plans on what to do next. Colonization of Callisto and perhaps Ganymede would be beautiful.
  • by iamlucky13 (795185) on Tuesday October 26, 2004 @11:37PM (#10638851)

    NASA just finished building their new supercomputer [slashdot.org], and it's already been slashdotted. Actually, the second try worked, but the first one gave me a server busy message.

    The NASA TV feed is pretty interesting. They just went through a series of photos from one of the cameras taking shots at different wavelengths which very dramatically displayed the effect of wavelength "windows." They also mentioned that they sampled the upper atmosphere on the way through, so maybe there will be something interesting to tell as a result of that.

  • First I get my memory erased, then I get sent all over the solar system, THEN I become an object of scorn for the whole world.

    When I finally get some peace and quit out here on Titan you bastards send probes to look at me.

    Go look for Mr. Rumfoord! Leave me alone!

    (If you don't recognize my nick ignore me.)

  • The moat [nasa.gov] around Marvin the Martians holiday home
  • remembered to take the lens cap off [nasa.gov]...
  • So, has NASA posted any pictures of Winston Niles Rumfoord or his dog yet?

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