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Venus Transit Finished

KjetilK writes "Venus is just about to cross the solar disc. Direct from the control room in the Frogner Park in Oslo, I'm pleased to inform you that we have a great webcast, and as far as we know, it is the only webcast that still stands upright... Slashdotters, do your worst! ;-) A Venus transit is one of the most unique astronomical events in our time, in fact, no living person has witnessed it before today. And today, more people have seen it from the park where I'm sitting that in the rest of human history. Also, it had tremendous importance for the development of science, as it gave the first absolute measurements of distances in the solar system. Especially in 1769, a transit made science take huge leaps forward. And BTW, New Zealand and Australia were 'discovered' in the process" Some nice photos from the UK, photos from vt-2004.org, and if you missed it, it'll be eight short years till you can try again.

20 of 220 comments (clear)

  1. Another article by Mz6 · · Score: 5, Informative
    For those insterested, the poster really didn't leave any links to explain some of his claims about distances and the discovery of NZ and Australia.. This article I found explains most of it in detail.

    Snippet:

    How transits can determine distances:

    In 1716, Edmond Halley was the first astronomer to suggest transits could be used to work out how far away the Sun is - also known as AU. Once this was known, the distances to all the other planets in the Solar System could be calculated.

    If the transit was measured from several different places on earth, Halley reasoned, there should be a slight difference in the visible track across the sun. But this shift is so slight it is difficult to measure directly. Instead, the time at four different points during the transit can be noted down. These are: the first moment when Venus touches the Sun's disc, the moment when it is completely inside the disk, the moment when it makes contact with the other side of the disk on its way out, and the last moment of contact.

    Astronomers can then compare these four timings as seen from different locations, a known distance apart. Using some fairly simple geometry the distance between the Earth and the Sun can be calculated.

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    Hmmm.
    1. Re:Another article by bdeclerc · · Score: 3, Informative

      Yep, and they were off by a factor 20, whereas the Venus method allowed 18th century astronomers to calculate the distance to within about 10% of the correct value.

      Reference:
      Greeks

  2. Re:WTF!!!? by Anonymous Coward · · Score: 3, Informative

    Well, if you would read the Science section, you would see it did indeed get posted a while ago.

    Though, even if it didn't, there are websites other than /. ...

  3. Heard about this on NPR this am by jamesdood · · Score: 4, Informative

    sounded pretty neat, they have a good write up here Since I missed it glad someone took some pictures!

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    *narf!*
  4. Re:WTF!!!? by Bill_Mische · · Score: 3, Informative

    Possibly because the best place to observe this wasn't in the US? The BBC and ITV having being flogging this for a few days so we all knew about it.

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    Boring Old Fart (40, married, 3 kids...er no...make that 49, married, 3 grown up kids...it's been a long time)
  5. Re:In case of Slashdotting-Article Text by lubricated · · Score: 1, Informative

    huh... huh... huh... He said rectum

    --
    It has been statistically shown that helmets increase the risk of head injury.
  6. New Zealand / Australia by kakapo · · Score: 2, Informative

    Strictly speaking, New Zealand and Australia were both 'discovered' (by both Europeans, and their indigenous inhabitants) well before 1769, when Cook sailed to Tahiti to observe the transit. Cook's contribution was mapping the coastline of New Zealand with much greater accuracy, and mapping big chunks of the eastern coast of Australia.

    His biggest discovery was what he didn't find -- at the time, there was considerable belief in the idea of a "great southern land" somewhere in the Pacific, and Cooks three voyages, when taken together, cross-hatch the Pacfic and demonstrate that it contained no large and undiscovered landmassess.

  7. Venus on your desktop! by dotz · · Score: 4, Informative
    1. Get xplanet!
    2. Setup instructions (despite BSD-related site, pretty useful even on win32!)
    3. ???
    4. NICE DESKTOP!
  8. Australia by pubjames · · Score: 3, Informative


    Recording the transit of Venus was the official reason for Cooks voyage to Tahiti - he carried precise scientific instruments to record it, as recording it from different locations around the world would provide valuable information.

    Once this was done, Cook opened a secret envelope which contained the real reason for his voyage - to discover the great unknown land mass in the south (Australia) and claim it for England.

  9. Photos by Seft · · Score: 2, Informative

    Here are some photos from Winchester College, UK: Here and one that I took, Here, and Here (colour corrected)

  10. Full Color Telescope Picture by gdavidp · · Score: 2, Informative

    There is a great picture of the event posted by a Canon 10D owner from Digital Photography Review website. He used an expensive filter and telescope.

  11. Re:Next Time by sonicattack · · Score: 2, Informative

    Here are images taken with a regular interval, which can be retrieved with wget, and combined into a nifty time-lapse film, for example with Mencoder:

    mencoder -mf type=jpg mf://*jpg -o movie.avi -ovc lavc -lavcopts vcodec=mpeg4:mbd=2:trell:cbp:mv0

    I'm usure about how copyright for the images works and if someone would be allowed to make such a film publicly available. That would lessen the burden on that server. Perhaps. :)

  12. Re:Simultaneous Transit with the Space Station by Anonymous Coward · · Score: 1, Informative
  13. Re:Mercury by lecithin · · Score: 4, Informative

    If Mercury's orbit was not inclined with respect to the orbit of the Earth, Mercury would transit across the Sun every 116 days (the period of time between two identical configurations Sun-Mecuri as seen from the Earth; i.e. synodic period). But the inclination of Mercury's orbit (7 degress) causes that most times Mercury's path crosses "above" or "below" the solar disc, without a transit taking place. Therefore, on average, there are only 13 transits per century, separated by intervals ranging from 3.5 to 13 years. Currently, transits of Mercury can only occur during the months of May and November. Stolen From http://www.am.ub.es/~emasana/mercuri2003/faq_eng.h tml

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    It could be worse, it could be Monday.
  14. Re:Mercury by tommy_teardrop · · Score: 4, Informative

    With thanks to Google:

    Transits of Mercury: 2001-2100

    Date Time

    2003 May 07 07:52
    2006 Nov 08 21:41
    2016 May 09 14:57
    2019 Nov 11 15:20
    2032 Nov 13 08:54
    2039 Nov 07 08:46
    2049 May 07 14:24
    2052 Nov 09 02:30
    2062 May 10 21:37
    2065 Nov 11 20:07
    2078 Nov 14 13:42
    2085 Nov 07 13:36
    2095 May 08 21:08
    2098 Nov 10 07:18

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    -- IANAL, BIPOOTV
  15. These pics are amazing... by hkfczrqj · · Score: 2, Informative

    Just look at these pictures. They were taken by the Swedish Solar Telescope.

    Too bad I couldn't see the transit from my place. Maybe in 2012 I can be in the right location. Does any Hawaiian, Japanese or Polinesian slashdotter have a room for rent in June 2012? :)

  16. Re:pics i took by bonius_rex · · Score: 2, Informative

    This is slashdot and all, but if you'd read the words, instead of just looking at the pictures, you'd have seen this:

    Welcome to my poor man's experience of the Venus Transit of 2004, from the far eastern island of Singapore.

  17. BBC Program tonight. by amembleton · · Score: 2, Informative

    Tonight there is an hour long program on BBC 2 at 11.20PM about the Transit of Venus.

    More Information

  18. Spectacular Venus Transit links by GatorMan · · Score: 2, Informative

    http://www.jackstargazer.com/VTLinks.html

    and

    Real webcast of event:
    http://www.miamisci.org:8080/ramgen/starga zer/SG04 22.rm?usehostname

  19. Re:solar disc? by ViolentGreen · · Score: 2, Informative

    I believe the term "solar disc" refers to the Sun as seen from the earth. An object cannot pass in front of another object without a reference point to determine where the front is. I guess it's just a little more percise to say it that way.

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