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    Google Homepage ~ May 17, 2017

    Antikythera mechanism
    Generally referred to as the first known analogue computer,[26] the quality and complexity of the mechanism's manufacture suggests it has undiscovered predecessors made during the Hellenistic period. Its construction relied upon theories of astronomy and mathematics developed by Greek astronomers, and is estimated to have been created around the late second century BCE. In 1974, Derek de Solla Price concluded from gear settings and inscriptions on the mechanism's faces that it was made about 87 BC and lost only a few years later. Jacques Cousteau and associates visited the wreck in 1976 and recovered coins dated to between 76 and 67 BC.

    A schematic representation of the gearing of the Antikythera Mechanism, including the 2012 published interpretation of existing gearing, gearing added to complete known functions, and proposed gearing to accomplish additional functions, namely true sun pointer and pointers for the five then-known planets, as proposed by Freeth and Jones, 2012. Based also upon similar drawing in the Freeth 2006 Supplement and Wright 2005, Epicycles Part 2. Proposed (as opposed to known from the artefact) gearing crosshatched.

    This reminds me of bicycle gearing, both internal planetary hubs and external derailleurs and gears. You can see were I might get my celestial mechanical fascination from, in relation to bicycles. Fascinating in deed!

    The waning crescent Moon hangs low with Venus and Mercury at dawn.
    (The visibility of Mercury is exaggerated here; binoculars will help.)

    Monday, May 22,2017

    Look east in early dawn Tuesday morning for Venus with the waning crescent Moon, as shown above. And can you make out Mercury yet? (In these scenes, the Moon is always shown three times its actual apparent size.)
    New Moon is on Thursday, May 25th, 2017. This is another lunar cycle closer to the Great Solar Eclipse of August 21st, 2017. The alignment between Sun and New Moon is getting tighter and tighter with each successive cycle, with three cycles to go. Let's hope for clear skies. (see above posting of April 2nd, 2017)
    The sky has cleared and we may get a nice sunset this evening. Hopefully the low clouds don't roll in over night.


    Friday, June 9
    This evening, look for Saturn a few degrees to the right of the just-past-full Moon. They rise, together with Scorpius, in the southeast, just after sunset, and then transit from east to west over the course of the night. Watch the Moon pull a bit farther away (eastward) from Saturn as they cross the sky together through the night, setting in the west as the Sun rises in the east.
    The full Moon of June is traditionally called the Strawberry Moon or . . . (wait for it . . .) the Honey Moon. Perhaps because it rides low across the sky, where summer haze may turn it honey-yellow all night.
    Wednesday, June 14
    Saturn is at opposition tonight. For just a few days around opposition, Saturn's rings turn a little brighter than usual with respect to Saturn's globe, a phenomenon called the Seeliger effect. It's caused by ring particles backscattering sunlight toward the Sun (and, right now, Earth).

    Cassini’s Grand Finale Orbits Set to Begin

    I remember the planing, building and then 20 years ago, the launch of Cassini. What a trip and talk about a Viking Funeral!
    • CommentTimeJun 9th 2017
    WANTED: For the downtube on my Stumpy and in the style likeness of the "StumpJumper" logo below, a "TrumpDumper" decal set.

    • CommentTimeJun 10th 2017
    Shady John:For everyone who has climbed Nate Harrison Grade:

    A friend of ours did some archaeological excavations of Nate's home in grad school.
    • CommentAuthorShady John
    • CommentTimeJun 27th 2017
    Why we shouldn't complain about having to fix a flat:


    The Tea Pursuit, which aimed to test one’s mettle while holding a cup and saucer on a moving bicycle…
    (Ah, the places you'll go with a bike share!)
    The Chap Olympiad

    Splendid group of eccentric Brits, the world’s best dressed, descend on Bedford Square Gardens for Britain’s most eccentric sporting event. A midsummer ceremony, celebrating the weird, wonderful and wacky. A day-long celebration of diversity, set to the backdrop of a traditional summer garden party with a roster of live entertainment including eleven Olympiad games. The Chap Olympiad is designed to reward panache rather than sporting prowess and the games require the minimum amount of physical exertion. Not since the days of Bee versus Pigeon Racing during the Victorian times have so many befuddled anarcho-dandies and gin-addled punks been gathered together under one parasol.

    The Chap Olympiad — A Very British Day Out

    (Seems quite the "tweedy" event!)
    • CommentTimeJul 31st 2017
    Riding the Burke-Gilman trail today ...

    Burke-Gilman trail
    From Sky and Telescope

    By week's end, Venus is closing right in on delicate little Mars, low in the eastern dawn. Venus (magnitude –3.9) is in Leo, just above Mars) Notice how Leo appears to be leaping up from the rising Sun's position. It gets higher, relative to the Sun, by one degree per day. This is what's meant by a helical (Sun) rising. (The Sickle is the mane of the lion, looking upward, and Regulus is the front paw.)