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Tar Pitch Drop Captured On Camera

Posted by Soulskill on from the you-can-now-die-happy dept.

New submitter Ron024 sends this news from Nature: "After 69 years, one of the longest-running laboratory investigations in the world has finally captured the fall of a drop of tar pitch on camera for the first time. A similar, better-known and older experiment in Australia missed filming its latest drop in 2000 because the camera was offline at the time. The Dublin pitch-drop experiment was set up in 1944 at Trinity College Dublin to demonstrate the high viscosity or low fluidity of pitch — also known as bitumen or asphalt — a material that appears to be solid at room temperature, but is in fact flowing, albeit extremely slowly. ... The Trinity College team has estimated the viscosity of the pitch by monitoring the evolution of this one drop, and puts it in the region of 2 million times more viscous than honey, or 20 billion times the viscosity of water. The speed of formation of the drop can depend on the exact composition of the pitch, and environmental conditions such as temperature and vibration."

27 of 142 comments (clear)

  1. Ok.... by Anonymous Coward · · Score: 2, Interesting

    ....now do that with glass

    1. Re:Ok.... by i+kan+reed · · Score: 4, Informative

      Didn't you notice that the titration device was made of glass and showed zero sign of change? That's because glass isn't an amorphous solid.

    2. Re:Ok.... by Sockatume · · Score: 2

      I know you're just saying that to screw with pedants... but I hate you anyway.

      --
      No kidding!!! What do you say at this point?
    3. Re:Ok.... by Anonymous Coward · · Score: 3, Informative

      Glass *is* an amorphous solid. The point is that it isn't some sort of superviscous liquid.

    4. Re:Ok.... by slashmydots · · Score: 2, Insightful

      Nobody seems to be able to decide what the heck glass is. You've got the controversial cathedral glass thickness reports. Then you've got the slightly more easily provable fact that it shatters. The consensus seems to be that it's not completely solid and from there, people can argue all they want. But since the tar was inside glass and we have to assume the glass morphed, their measurement isn't completely accurate. So...time to start the experiment over again, lol

      But that's not the only reason. The luminosity in the room changed slightly and the material is black. That means it changed temperature slightly, which over 69 years could cause significant viscosity measurement inaccuracies. Plus, the room probably wasn't even properly climate controlled anyway.

      So let's start it over and do it right this time! Forget landing on Mars, we need to know the viscosity of tar, damn it!

    5. Re:Ok.... by Anonymous Coward · · Score: 5, Informative

      Nobody seems to be able to decide what the heck glass is.

      Actually the Nature article on the pitch drop states:
      "Scientists used to believe glass to be a slow-moving liquid as well — in part because old church window panes are thicker at the bottom — but it is now considered a solid."
      and points to this as a reference. Zhao, J., Simon, S. L. & McKenna, G. B. Nature Communications

      Nature is a fairly reputable journal so I think I'll go with glass as a solid for the time being.

      The issue regarding the windows panes appears to be that the differing thicknesses from one side of the window to the other is because of the manufacturing method. Also they put the thicker side at the bottom in order to prevent breakage because they weren't idiots.

    6. Re:Ok.... by MozeeToby · · Score: 4, Informative

      The cathedral glass reports have nothing to do with glass flowing and everything to do with how glass was made hundreds of yeas ago.

    7. Re:Ok.... by Anonymous Coward · · Score: 2, Insightful

      It would be very likely because that is exactly what they did for stability reasons.

    8. Re:Ok.... by MozeeToby · · Score: 2

      If I hand you a piece of glass that is noticeably thicker on one end and tell you to put it in the window, you're not going to put the thick side down? Almost all glass is found that way because it was installed that way on purpose for stability reasons and, arguably more importantly, to prevent water pooling at the bottom of the window seal. I say "almost" because there are, in fact, instances where it was installed incorrectly.

    9. Re:Ok.... by jason.sweet · · Score: 2

      So they would spend decades carving the ornamentation, but only do a half-ass job installing the glass?

    10. Re:Ok.... by K.+S.+Kyosuke · · Score: 2

      Even by the 90s, the description of glass as an amorphous solid was unanimous among all material science work I've seen.

      "Folk knowledge" like this is to some extent present in every field. For example, in the field of linguistics, "everybody knows" that Inuits have hundreds of different words for snow...except, well, they don't. If the piece of knowledge is peripheral (= not often exercised, as opposed to, say, Newton's laws of movement which you see around yourself exercised all the time), AND difficult to verify at the same time, there's always potential for blunders like these to happen because few people bother to check.

      --
      Ezekiel 23:20
  2. Dripping tar, drying paint by Anonymous Coward · · Score: 5, Funny

    Must be a slow news day.

    1. Re:Dripping tar, drying paint by davester666 · · Score: 2

      I'm just hoping they also have a slow-motion video of the drop, so we can see all the fine details.

      --
      Sleep your way to a whiter smile...date a dentist!
  3. Like an Old Guy at the Urinal: Forever for a Drop by InitZero · · Score: 5, Funny

    Are you done yet in there, Grandpa?

    Cheers,
    Matt

  4. And I thought... by roc97007 · · Score: 2

    *I* had a lot of time on my hands...

    --
    Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
  5. OK, well... by synaptik · · Score: 2

    OK, well I'll mark that one off my Bucket List now...

    --
    HSJ$$*&#^!#+++ATH0
    NO CARRIER
  6. Not too bad to watch by h4rr4r · · Score: 5, Funny

    The video was not too bad, far less boring than baseball.

    1. Re:Not too bad to watch by Aelanna · · Score: 2

      I actually find the pitcher-batter mind games, statistics, and pitch mechanics and aerodynamic physics of baseball to be far more interesting than any other mainstream sport. Your mileage may very, I suppose.

  7. Re:Moore's Law Catches Glass Bubbles on the move by h4rr4r · · Score: 4, Insightful

    Glass bubbles do no rise in panes of glass. Glass is not a liquid.
    http://io9.com/the-glass-is-a-liquid-myth-has-finally-been-destroyed-496190894

  8. Why does the equipment move? by wonkey_monkey · · Score: 4, Interesting

    Why does the funnel clamped to the stand move just at the moment of the breakage? I call shenanigans!

    --
    systemd is Roko's Basilisk.
    1. Re:Why does the equipment move? by Antipater · · Score: 2

      I'm at work and can't see the video. But if you're saying that the funnel jerks upwards as the drop falls away, that's to be expected. The clamp assembly no longer has to support the weight of the drop, so it should "bounce" upward a little before reaching a new, less-weighed-down equilibrium position.

      --
      Everything is better with chainsaws.
  9. money quote by phantomfive · · Score: 4, Interesting
    This quote from the article is so great:

    “I have been examining the video over and over again,” Mainstone says, ”and there were a number of things about it that were really quite tantalizing for a very long time pitch-drop observer like myself.”....Mainstone, who has spent most of his life waiting to see a drop fall with his own eyes, congratulated the Trinity College team.

    --
    "First they came for the slanderers and i said nothing."
  10. Now disprove the glass pane urban legend by 140Mandak262Jamuna · · Score: 2, Interesting
    Claim A: glass panes in very old cathedrals in Europe is thick at the bottom and thin at the top because glass had flowed over the centuries.

    Claim B: Claim A is an urban legend. citation 1 citation 2 and you can find more on the net.

    Claim C: Claim B is an urban legend.

    Now can someone set up some cameras and prove Claim C? That would be supercool, one level recursive urban legend.

    --
    sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
    1. Re:Now disprove the glass pane urban legend by sjames · · Score: 5, Funny

      Well, they tried but the camera had a glass lens and went out of focus for some reason.

  11. 69 years of the worst dinner conversation ever by DougOtto · · Score: 3, Funny

    Wife: What happened at work today, honey?

    Scientist: Oh nothing...

    Lather, rinse, repeat.

    --
    Solving Unix problems since 1989...
  12. Re:Tar Roads by RabidReindeer · · Score: 4, Funny

    Does this mean that tar-based road surfaces are slowly flowing downhill?

    Not so slowly, now that it's summertime.

  13. Re:Tar Roads by Jarik+C-Bol · · Score: 4, Interesting

    I read a blog by a guy who had walked across the United States, from the Atlantic in Georgia, to the Pacific in California. He crossed Midland TX in August, and noted that during the middle of the afternoon, walking down the highway, while traffic was low, there was this odd constant popping/crackling sound. He finally stood still and investigated it for a while, and discovered that it was the road tar making the sounds as is slowly boiled in the summer sun. little bubbles would form, bulge out the surface, and then burst with a tiny 'pop'. I don't know if this answers your question, but it seemed to be a good time to tell that story.

    --
    I've decided to Diversify my Holdings. I've divided my cash between my left and right pockets, instead of all in one.