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    Venus Approaching The Sun
    By Tommaso Dorigo | June 4th 2012 08:41 AM | 16 comments | Print | E-mail | Track Comments
    About Tommaso

    I am an experimental particle physicist working with the CMS experiment at CERN. In my spare time I play chess, abuse the piano, and aim my dobson...

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    For the second and last time this century, the planet Venus will pass over the visible disk of our Sun for observers located in the Americas (in the evening of June 5th) and western Europe (in the morning of June 6th). The event has a noteworthy scientific value -particularly for exoplanetary searches-, but it is also quite spectacular to observe, if you have some modest equipment (but you should be able to spot it with your naked eye, provided you only look through a thick-smoked glass; never look at the Sun directly!). The added value is that probably none of us will be around the next time this event occurs, in 2117.

    I watched the 2004 transit of Venus with telescopes that local amateur astronomer associations had made available in Padova, and I enjoyed it a lot. To watch the sun directly your telescope will need to have custom filters - you would be instantly blinded if you aimed a unprotected optical instrument at the Sun. If you want to observe the transit your best bet is to try and determine which is the closest place where amateurs are gathering.




    While we wait for spectacular pictures of the transit (they will look more or less like the one shown above, which was taken in 2004) it is nice to see how Venus looks like, if photographed through the mastery hands of Damian Peach, one of the most skilled planetary imagers in the world: yesterday Venus was just at 3.5 degrees from the Sun, so it must not have been trivial to locate the planet in daylight. The result is the beautiful picture on the right. Note how the Sun's light is almost circling around the planet's disk, partly thanks to Venus' thick atmosphere.


    Speaking of Damian Peach, I cannot resist posting here a award-winning picture of Jupiter with its moons Io and Ganymede, which he took two years ago. There simply are no words to describe the beauty and amazing level of detail that is discernible in the image. Pictures of this quality are only possible to Hubble and to huge earth-based telescopes with adaptive optics, and to maybe one or two amateurs in the world.

    Comments

    The Jupiter one is really really beautiful!

    Don't look at the sun through smoked glass! When looking at the sun at eclipses or the like, one should never use home made equipment like smoked glass, old camera film, very dark sunglasses or the like. Your equipment will not stop the full UV spectrum, and you may end up damaging your eyes severely. As your eyes will not receive much visible light, your pupils will dilate, only making matters worse.

    dorigo
    It is right to be overcautious with these advices Christian. Thanks
    T.
    I'm definitely planing on watching this if the weather cooperates (it is raining right now over northern California; rain in June??)

    Hank
    Right???  We live in the sunniest place in America, I have the telescope queued to reflect on a wallboard, and we get rain the day before.  Here's hoping for clearing tomorrow.
    Want more no-nonsense, independent science? Buy Science Left Behind
    Bornerdogge
    I suppose an hour of car travel or so will bring you in some sunny place?

    Here in Belgium things are much worse :(
    UvaE
    There's lots of cloud on the radar in parts of your state. We're in store for a beautiful day, but unfortunately I have to attend an indoor ceremony!
    rholley
    Those two pictures from Damian Peach:

    Che bella cosa!  (Don’t worry, I haven’t uploaded myself to YouTube — yet.)
     
     
    Robert H. Olley Quondam Physics Department University of Reading England
    UvaE
    Whenever I see the words " Che bella cosa!" i can't help but think of Caruso's song:

    Here's a Pavarotti version:
     
     
    UvaE
    I love that picture of Jupiter with two of the Galilean moons.
    rholley


    And just to think that Ganymede is 41% the diameter of the Earth, showing how huge those weather features on Jupiter are.  The bands are called belts and zones, ζώνη being the Greek for "belt".

    Here is a pie chart showing the masses of the Galilean satellites.
     
    Io is pretty massive for her size, which shows that a lot of volatiles must have been lost due to tidal heating so close to Jupiter.

     * * * * * * * * * * * *

    As for their names:

    The names that eventually prevailed were chosen by Simon Marius, who discovered the moons independently at the same time as Galileo: he named them at the suggestion of Johannes Kepler after lovers of the god Zeus (the Greek equivalent of Jupiter): Io, Europa, Ganymede and Callisto, in his Mundus Jovialis, published in 1614.

    Galileo steadfastly refused to use Marius' names and invented as a result the numbering scheme that is still used nowadays, in parallel with proper moon names. The numbers run from Jupiter outward, thus I, II, III and IV for Io, Europa, Ganymede, and Callisto respectively. Galileo used this system in his notebooks but never actually published it. The numbered names (Jupiter x) were used until mid-20th century when other inner moons were discovered, and Marius' names became widely used.


    (from Wikipedia article)
    Robert H. Olley Quondam Physics Department University of Reading England
    UvaE
    I'm glad Marius came along---I'm not too fond of numerical names for astronomical objects.
    The Stand-Up Physicist
    For the second and last time this century, the planet Venus will pass over the visible disk of our Sun for observers located in the Americas and western Europe on June 6th. 
    NOTE: this was written by someone in Italy.  They can see the event on the morning of June 6th.  AMERICANS have a chance this evening, June 5.  Go to http://www.transitofvenus.org/ for your app.


    The state of Massachusetts may have rain clouds at that hour, bummer.
    dorigo
    That's right Doug! Sorry for the confusion - will change the text.
    Cheers,
    T.
    Hank
    I live in a place with 300 days of sunshine a year and even we had rain yesterday - June, of all times.  Here's hoping it clears up.
    Want more no-nonsense, independent science? Buy Science Left Behind
    Got a brief look this morning, before the cloud set in. Rather more solar activity this time than in you picture from 2004.