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Science Technology

Dust Samples Returning to Earth at 28,860 mph 48

DjBenBen writes "After a 2.88 billion mile round-trip journey, NASA's Stardust mission is nearing Earth with comet and interstellar dust particles that could help provide answers about the origins of the solar system. Better yet, the velocity of the sample return capsule, as it enters the Earth's atmosphere at 28,860 mph, will be the fastest of any human-made object on record."
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Dust Samples Returning to Earth at 28,860 mph

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  • by naden ( 206984 ) on Thursday December 22, 2005 @06:47AM (#14316172)
    Thats like a speeding bullet stuck in the back end of a bat out of hell

    Signed Smegger.
  • That's fast (Score:3, Funny)

    by X-Gamer ( 937169 ) on Thursday December 22, 2005 @06:47AM (#14316173)
    At such velocity,I sure hope the capsule won't add to the dust.
  • 28,860 mph is just over 8 miles per second. When compared to lights speed of 186,000 miles per second in a vacume, it isn't much to write home about. Granted it's still fast, and I don't really think I want it hitting my appartment, or even your mom's house...

    -Rusty
    • maybe it'll hit my mother-in-law's house
    • I fail to understand what is the point in comparing natural radiation speed in a vacuum (don't declinate, if you are not speaking Latin) with artificial physical object speed in the atmosphere.
      • by Tango42 ( 662363 ) on Thursday December 22, 2005 @08:14AM (#14316477)
        Because the speed of light in a vacuum is more important than just being the speed light travels in a vacuum. It's a fundamental speed that turns up in lots of places - it's the speed of light, the speed of gravity (probably, measurements place it within the margin of error), the "speed limit" of the universe, the square root of the constant of proportionality between mass and energy, and probably a few other things I can't remember/don't know.

        The most important reason is the speed limit one - once you start getting close to c strange things start happening, which is interesting and worth thinking about. Once we get to the stage of having space probes travelling at relativistic speeds we can do all kinds of fun stuff, like sending them to other stars, etc.
        • It's a fundamental speed that turns up in lots of places

          Not here. Not nearly. Moreover, who cares about relativistic effects on interstellar probes? The travel may seem to be short by the probe's point of view, but it will still take years for us on Earth. And it's not difficult to build a robot with infinite patience.

          • The fact that it's relativistic isn't important for a probe, no, it's just the fact that it's very fast that's important and relativistic speeds are the fasted you can get.
            • "You will begin to touch heaven, Jonathan, in the moment that you touch perfect speed. And that isn't flying a thousand miles an hour, or a million, or flying at the speed of light. Because any number is a limit, and perfection doesn't have limits. Perfect speed, my son, is being there." - Chiang (Jonathan Livingston Seagull)
  • by doderich ( 882969 )
    After all, an organization must have a flawless track record before they're allowed to accelerate a projectile at 28,860 miles per hour towards the earth.
    • After all, an organization must have a flawless track record before they're allowed to accelerate a projectile at 28,860 miles per hour towards the earth.


      Unfortunately for the inhabitants of Utah, the guys at NASA put the decimal point in the wrong place again. The Probe will be entering at a new revised velocity of 288,600 Miles per hour
  • by Nuffsaid ( 855987 ) on Thursday December 22, 2005 @08:10AM (#14316466)
    Let's hope for a smoother reentry than that of the Genesis probe [nasa.gov]
  • Interstellar? (Score:3, Interesting)

    by Tango42 ( 662363 ) on Thursday December 22, 2005 @08:18AM (#14316492)
    What's the definition of interstellar dust? Wouldn't the probe have to leave the solar system to get it, which it obviously didn't?

    I would have thought interstellar dust was what's beyond the heliopause, anything inside is interplanetary at best.
    • Re:Interstellar? (Score:4, Informative)

      by Vellmont ( 569020 ) on Thursday December 22, 2005 @09:00AM (#14316634) Homepage
      The dust is interstellar because its origin is outside our solar system. That is it isn't bound gravitationally to our sun. Interstellar dust doesn't just sit around between stars, it moves relative to our solar system. IIRC it moves a lot faster than the local inter-planetary dust of our solar system (around 30 km/sec). Because of this there's interstellar dust blowing through our solar system all the time.
      • Re:Interstellar? (Score:3, Interesting)

        by Tango42 ( 662363 )
        And they somehow filter the dust based on its speed? The amount of interstellar dust is presumably far smaller than the amount of interplanetary dust, and I can't see how they could only get the interstellar stuff...
        • Good question. I'm not sure how they determine which is interstellar, and which is interplanetary. Like another post says it may be on penetration depth into the aerogel. Or perhaps they have some way of stopping the lower speed stuff in some other medium before it reaches the aeorogel.
    • Re:Interstellar? (Score:3, Informative)

      by Z0mb1eman ( 629653 )
      I believe the "interstellar dust" the article refers to comes from comets (presumably from the tail?), which are generally interstellar... not sure why the article feels the need to mention "cometary and interstellar dust" in that case, but:

      "Locked within the cometary particles is unique chemical and physical information that could be the record of the formation of the planets and the materials from which they were made," said Don Brownlee, Stardust principal investigator at the University of Washington, Se


      • which are generally interstellar... not sure why the article feels the need to mention "cometary and interstellar dust" in that case, but:


        Actually no on both counts. It's not known if comets are from our solar system, or from the proposed "ort cloud" that's losely bound to our solar system. The interstellar dust is truly interstellar. The mission was to collect both comet dust and interstellar dust. The results of the mission should give evidence for comet origins.
  • What's expected accuracy? What is the possibility to miss expected landing site and hit some populated area?
  • but before anything when is a f.....g blog a source of accurate information ??

    The "something wrong" is that a mobile animated with a speed superior to 24.000 km/h cannot enter the terrestrial gravity ... it escapes it.

    That's it.
    • ...with a speed superior to 24.000 km/h cannot enter the terrestrial gravity...

      Boy, you just fell off the wrong tree and hit every branch on the way down.

    • Can you say "Aerobraking"? And, ignoring that, if said 'mobile' impacts the planet i seriously doubt it will escape.
    • Your physics teacher needs to be fired/lynched/shot (depending on local laws)

      First of all, your units are wrong. Escape velocity is around 25,000 MILES per hour.

      Second, if the object is actually headed *towards* earth, it's own trajectory will preclude it from "escaping". Do you think anything traveling faster than escape velocity will simply quantum-tunnel through the earth?

      Third, lots of meteors enter the earth's atmosphere every day with velocities on the order of, or exceeding, the "escape velocity" o
      • Actually, yvesdandoy used the right units (SI), he just got the wrong number from a table with the wrong units. ;-) Let's face it: only 5% of the population on Earth still has a problem with the metric system. It seems ignorance cannot be cured.

        The article posted here at /. refers to "mph". I see too often that students use such nonsense. Of course, they have no concept for units. If someone had told them at school to write "km/h" instead, then the students may realize one day that this means distance divid
        • Well, I stand by my assertion that yvesdandoy used the wrong units...as he clearly pulled a number out of some reference and blindly attached a set of units to the end of it...clearly demonstrating a lack of knowledge of the physical system he/she was trying to comment on...and therefore using the wrong units attached to a (basically) correct number due to this lack of knowledge. ToMAYto, ToMAWto :p In any case...yvesdandoy's physics teacher should indeed be fired/shot/lynched as I earlier suggested.

          And y

        • BTW the cross section of neutrinos interacting with hadrons and leptons is so small that most neutrinos penetrate earth without interaction. Our probes are just not made out of neutrinos.


          And if the probe were made out of neutrinos you would have a point. Of course it's not, so I'm sorry to say you just sound like a smartass trying to throw your knowledge around.
  • by m.h.2 ( 617891 ) on Thursday December 22, 2005 @12:00PM (#14317989) Journal
    ... welcome our new Supersonic Dust Particle Overlords.
  • To be firing objects back at earth? I don't care about them sending them out to space or landing on other planets, but I feel like I have a target on my back when they start returning them back to earth at such velocities.
  • Someone call the WILDFIRE team and start getting them decontaminated...
    • Someone call the WILDFIRE team and start getting them decontaminated

      WoOT! Andromeda Strain. The first SF film I remember oriented toward computers that weren't some variant on a talking card sorter! Brilliant flick.

  • ...the bodies of the recently deceased returning to life and attacking and devouring the living, at least you know why.

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