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First Photos of the Reentry of the ATV "Jules Verne"

Posted by kdawson on from the down-in-flames-seventy-five-km-up dept.

White Yeti writes with news of the reentry breakup of the ESA's Automated Transfer Vehicle. All went as planned, and the ESA blog has preliminary photos. An international team of observers, in two aircraft south of Tahiti, saw a series of explosions and over a hundred small pieces of debris. Observations were mostly made using optical cameras and spectrographs. The two images on the ESA site are low-res samples, so we should get more spectacular images soon.

17 of 87 comments (clear)

  1. Camera phone funding by MosesJones · · Score: 3, Funny

    this is the "Hi res" 28k JPG image on the site. Anyone else get the feeling that they rushed up there to watch it and then someone said "I thought you said you'd bring the cameras" so it was then out with the mobile phones.

    The only real surprise is that these clips didn't hit Youtube first with a Tramps "Disco Inferno" sound track. Very cool stuff and it practically demands HD for a fireworks display with a billion dollar budget

    --
    An Eye for an Eye will make the whole world blind - Gandhi
    1. Re:Camera phone funding by 4D6963 · · Score: 3, Insightful

      Maybe it's because they had to huge use zooms since you know, the action took place quite a few tens (probably more than a hundred) kilometres away?

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    2. Re:Camera phone funding by Renegade+Lisp · · Score: 3, Insightful

      this is the "Hi res" 28k JPG image on the site. Anyone else get the feeling that they rushed up there to watch it and then someone said "I thought you said you'd bring the cameras" so it was then out with the mobile phones.

      Nice speculation, but the image you refer to is probably cut out from a much larger raw image. The URL has something about "800mm" in the name, which probably refers to an already somewhat decent telephoto lens having been in use. Definitely not your mobile phone!

    3. Re:Camera phone funding by meringuoid · · Score: 4, Informative
      If they sent up additional fuel for it, it could be re-used again and again

      For what? Its primary mission is to deliver supplies from Earth. Oxygen, water, food, fuel. While docked it acts pretty much as a walk-in wardrobe. Once its supplies are exhausted there's no further use for it; they load it up with rubbish and send it off to burn up. Then another one gets launched.

      It would probably be possible to redesign the ATV with a heatshield to allow it to come home intact. But that adds a lot of weight and drastically reduces its capacity as a cargo carrier; you'd only do that if you wanted to use it to carry human crews. Maybe that'll be done some day, but not right now.

      The only other use for the ATV while in orbit is for station-keeping. It can boost the Station's orbit, and some day an ATV may be given the mission of de-orbiting the entire structure. But there's no sense sending up more fuel to allow the ATV to continue working as a tugboat - that fuel would be delivered by, er, another ATV. So you might as well let that do the job.

      If there were other stations in near-Earth space, then keeping a spare ATV in orbit might make sense. It could ship equipment and perhaps crews between them. But right now there's nowhere to go from the Station except for back to Earth.

      --
      Real Daleks don't climb stairs - they level the building.
  2. Intentional Break-Up by Renegade+Lisp · · Score: 5, Informative

    I guess the summary could have been clearer about this being an intentional breakup during re-entry. The craft is designed to be destroyed after use.

  3. Question about atmospheric friction by Viol8 · · Score: 3, Interesting

    At what speed do you have to travel in the atmosphere before the cooling effect of air rushing past is overtaken by the friction effect and you start heating up again? I remember reading that concorde used to heat up on the outside but subsonic airliners don't. Does it have anything to do with the speed of sound?

    1. Re:Question about atmospheric friction by delt0r · · Score: 5, Informative

      It depends on the design/shape of the object. But generally a bit above mach 1. A blunt reentry object will cause a very strong shock wave at the front of the craft and will cause much more heating than a sharp object. Once you hit about Mach 5 IIRC the heating issue is getting quite serious. Reentry is about >7000m/s (speed of sound at that height does not really make sense) and causes extreme heating no matter what the design. For comparison Mach 1 is about 350 m/s at sea level.

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    2. Re:Question about atmospheric friction by Richard_at_work · · Score: 3, Interesting

      Wrong dimension - Concorde did expand, but lengthways (not to say it didnt expand widthways, it just didn't do it noticably).

      The flight engineers cap story is real - during the last flight of each Concorde at their retirement, each flight engineer placed his cap in the space between their console and the rear compartment bulkhead. The caps can be seen to this day, stuck there.

    3. Re:Question about atmospheric friction by Anonymous Coward · · Score: 5, Interesting

      Another example is the SR71 "Blackbird". It was designed so that all parts would fit perfectly only when it was very hot during flight. And since it lacked a heat resistant fuel containment seal, it would leak fuel in the ground until it took off, flew for some time to heat up and then it had to be refueled on air.

    4. Re:Question about atmospheric friction by damburger · · Score: 5, Informative

      Logical and correct, although supersonic heating has nothing to do with friction.

      Something moving through air pushes that air out of the way. At subsonic speeds (i.e. below the maximum speed the air as a fluid can move) this carries heat away from the aircraft. At supersonic speeds, the air simply cannot get out of the way quick enough, so piles up against the fuselage. This compression (not friction) creates heat.

      --
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    5. Re:Question about atmospheric friction by mbone · · Score: 3, Informative

      Here is a simple way to think about it -

      The kinetic energy of your (or an airplane's) motion gets converted into friction through turbulence and shock effects. Heat is just the velocity of atoms bouncing off each other, and the sound speed depends on the velocity of those atoms, and thus on the temperature.

      In an ideal gas, the absolute temperature is a measure of the energy, and thus is a constant times the square of the rms gas velocity. By the same consideration, for an idea gas, the speed of sound is (a constant) times the rms particle velocity. (That constant is the square root of the (adiabatic index /3), or about 0.7 for a monatomic gas.)

      So, you are correct. Speeds much slower than the speed of sound will generally be associated with small amounts of heating, which may be negligible compared to other effects, such as cooling caused by the air flow, while speeds much higher than the sound speed will generally involve heating to something much above the ambient temperature. (Generally, of course, airplanes are designed not to convert all of their kinetic energy into turbulence, but during re-entry, that is done pretty effectively.)

      The real gases in air are very non-ideal in the temperatures and pressures in re-entry so this simple theory is not realistic for speeds much above Mach 3 or so. It turns out that an engineer's rule of thumb is that the temperature in K is roughly equal to the speed in meters / sec, based on more realistic models of specific heat in the ionized plasma formed at these high speeds.

  4. Re:Why explode? by totally+bogus+dude · · Score: 3, Insightful

    It was designed to break up on re-entry, so if it made it to the ground in one piece some people would have been very angry.

  5. Concorde widens during flight by juletre · · Score: 3, Interesting

    I'll reply to myself with a link, after I did some googling. It contains a picture of the hat-episode. (search in page for "hat in the seam")

    --
    "he, who has quotes in his signature, is a douche" - unknown.
  6. Re:Why explode? by meringuoid · · Score: 5, Informative
    Why was an explosion a success? I would think getting it the ground in one piece would be better, but what do I know.

    The Jules Verne was carrying nothing but rubbish; it was intentionally burned up on re-entry. It's just a supply ship: it carries stuff up to the Station, serves as a little extra habitable volume while docked (I hear some of the crew have found it a very quiet place and have pressed it into service as sleeping quarters), and finally carries away waste and junk and incinerates the lot in the atmosphere.

    With the uncertainty over the future of the American manned capability, there is now talk of developing an upgraded ATV which would include a re-entry module, and make ATV into a complete manned spaceflight system. Mind you, there's always talk; ESA headquarters is full of extremely expensive paperwork relating to manned spacecraft that never flew. At least in this case there's something concrete to point at, though.

    --
    Real Daleks don't climb stairs - they level the building.
  7. I'm curious... by apodyopsis · · Score: 3, Interesting

    I had a hunt on the net - but did not find anything.

    did *anybody* ever get hit by a falling satellite?

    or radiation damage?

    or property damage?

    anybody know?

  8. Wow ! by o'reor · · Score: 5, Interesting

    The video of the re-entry is just beautiful !

    --
    In Soviet Russia, our new overlords are belong to all your base.
  9. Re:This shows a failure of imagination. by jmichaelg · · Score: 3, Insightful

    I don't doubt that there may be better uses for the craft but just how would you propose getting rid of the junk that accumulates? Remember, you have to be *positive* the junk doesn't stay in orbit so you have to substantially decelerate it somehow.

      That means some sort of rocket so either you have a "bus" that serves the function or you have a lot of little rockets slowing down the junk.

    On second thought, I suppose if their was some sort of rocket engine on the space station that was designed to eject junk at high speeds, you could both speed up the space station and dispose of the junk with one pop but lacking such an engine, I'm at a loss to think of how to better dispose of junk.