The Analemma. By Bill Busler. Memphis Astronomical Society

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  • Опубликовано: 16 ноя 2024

Комментарии • 49

  • @davidschandler48
    @davidschandler48 Год назад +2

    This is the best presentation of the analemma I have ever witnessed! I have made analemma-corrected sundials, done the computations, taught astronomy, etc. but I still learned a lot from this lecture. The southern accent is functional in that it puts the audience at ease while detailed reasoning is being slipped past the duct tape into their brains. Good job!

  • @freddydiazg
    @freddydiazg 4 года назад +2

    This is one of the best videos on this channel!

  • @bohol_netherlands
    @bohol_netherlands 4 месяца назад

    Such a great lecture!
    Thought I already knew a lot about analemma's but this gave so many new insights.
    It always good to have an attitude towards learning that there might be something new to learn.
    Near the end I was waiting for Mr Busler to come up with the effects on the position and form of the analemma by the slowing down of rotation of the earth axis over millions of years and the changes is the tilt of the earth axis, but he spared us those ones.
    👍

  • @hectorbart
    @hectorbart 2 года назад +2

    So glad I learned the correct pronunciation for this word.

    • @chugnorris7091
      @chugnorris7091 2 года назад

      Could have led to some rather awkward social situations, Anal-Emma

    • @rustyray420
      @rustyray420 Месяц назад

      Anal enema

  • @GLuft3
    @GLuft3 Год назад

    As others have stated: excellent treatment of the topic. Thank you!

  • @bordershader
    @bordershader 3 года назад +1

    This is amazing, so clear. Thanks!

  • @textbookscience6936
    @textbookscience6936 5 месяцев назад

    Great insights . Thanks

  • @meganrush532
    @meganrush532 2 месяца назад

    Very cool!!!

  • @hanrealistic
    @hanrealistic 6 месяцев назад

    What part of its velocity vector is northward or southward? How does it reduce the eastward component of it's motion? And How on earthat the solstices all of its motion is eatward.? Explain them with a 3D animation if possible. Showing Sun, Moon and Earth..

  • @honeybeesmusings
    @honeybeesmusings Год назад

    Translates into support... he says he doesn't know why that word. Many definitions. One definition of -support- is to provide a basis for the existence or subsistence of something. So it basically translates into provider of existence....

  • @Exilia2
    @Exilia2 3 года назад +2

    Excellent lecture!!
    Now there's something I been searching for an answer and didn't find yet: if the eccentricity of earth is 0.0167 which is an almost circle, why the analemma seems so elliptical? Should it be a more circular analemma? Any information would be helpful, thanks!!

    • @peat11
      @peat11 3 года назад

      i DON'T KNOW BUT HE IS LYING, IF THE EARTH IS MOVING AND ROTATING SURELY A SIDEREAL DAY WOULD LONGER NOT SHORTER AS HE SAYS BECAUSE THE EARTH HAS MOVED FURTHER.

    • @jameshealy1393
      @jameshealy1393 3 года назад

      @@peat11 It's sim to how, from 12 o'clock, the minute hand turns fully around the face, only to find the hour hand has sloped off, not actually catching it again until 5m 27s after 1. Bill's absolutely right, throughout. Take a look again at his section on the sidereal day, and, 7 months on, con*sider* that real star of info studded amidst Busler's galaxy of gravy gems on the analemma.

    • @jameshealy1393
      @jameshealy1393 3 года назад +1

      Bill's got you covered, there. (Nothing he didn't answer.) The eccentricity, he says (around 34m) effects no up-down component to the analemma, only a sideways shift. (Our fig-8 analemma collapsing to a horizontal bar line segment shadow of itself, when Earth orbits elliptically in, but rotates perpendicularly to, the ecliptic. I.e. zero obliquity & nonzero eccentricity.) Eccentricity only alters the right-left symmetry of an analemma. Earth's fig-8, vs, say, Mars's teardrop, is solely due to its axial tilt --- both the up-down deviations and the right-left departures for the 8 --- for the 2 dynamics Bill began with (the bulk of the analemma) namely, component & projection of Sun's apparent changing motion (from our wobbling, never-constant perspective) vs its practically regular actual motion along the celestial equator thru the zodiac of 59 arc minutes a day, or 69 Earth equator miles, its mean movement. To us, however, at equinox it's so busy crossing the equator, N-S'ly, that it only manages 54 arc mins eastward against the stars; only to make up that (5-min) shortfall by concentrating all its efforts eastward at solstices to zip 64 mins (4 more than 1 deg) the 5 mins extra bringing the annual average to its 360/365 daily clip.
      Terrestrial tilt has a 6-month period of effect, therefore 4 sections (coinciding with what we call 'seasons') and 4 nodes (Apr15, Jun13, Sept2, Dec25, see the equation of time at 53m); the eccentricity, a 12-month period, 2 humps (speed up & slow down), 2 nodes (Jan3 & Jul4). Eccen -> asymm (of whatever the tilt has turned up), fat wide or thin narrow; no tall or short oblong about it.

    • @Exilia2
      @Exilia2 3 года назад +1

      @@jameshealy1393 thanks for the explanation, I will keep collecting information, thanks again for share it

    • @peat11
      @peat11 3 года назад +1

      @@jameshealy1393 Then with all this sidereal complication why does the moon make the same figure eight.

  • @michaeldebortoli3179
    @michaeldebortoli3179 Год назад +1

    What about the moon anellemma

  • @hanrealistic
    @hanrealistic 6 месяцев назад +1

    Analemma Chile please

    • @bohol_netherlands
      @bohol_netherlands 4 месяца назад

      If you want an analemma for the moon, she Sky Tonigh app can create that as well for your location in Chile, you can follow the same steps but instead spot the moon on the sky map and tap it.

  • @shubhamkumar-nw1ui
    @shubhamkumar-nw1ui Год назад

    Analemma is Greek for support. My dirty brain 😢

  • @davebritton7648
    @davebritton7648 Год назад +2

    I just knew there'd be flat Earth idiots in the comments.🙄

    • @eladverde4674
      @eladverde4674 11 месяцев назад

      i see you didnt get any likes for your comment. who is the idiot?

    • @eladverde4674
      @eladverde4674 11 месяцев назад

      why so defensive dave? you guys always respond with name calling. childish.

    • @davebritton7648
      @davebritton7648 11 месяцев назад +2

      @@eladverde4674
      That wasn't defensive at all. That was a statement, and if you like, an attack. If you really think the Earth is flat, you are an idiot. If you, for reasons best known to yourself, pretend to think the Earth is flat on social media, you are an idiot.
      That is an opinion based on experience.

    • @eladverde4674
      @eladverde4674 11 месяцев назад

      @@davebritton7648 I used to be like you, angry. you just have to let go. cognitive dissonance. I think we both don't know the truth. It's frustrating,.,., isn't it?

    • @davebritton7648
      @davebritton7648 11 месяцев назад +1

      @@eladverde4674
      I don't know what you were angry about, but don't be trying to project your anger or 'cognitive dissonance' on to me.
      And I don't know about frustration, it's more a kind of vicarious embarrassment that members of the same species as me are such fools.
      Of course I have to weigh that against the huge amusement it has occassionally given me over time.

  • @michaeldebortoli3179
    @michaeldebortoli3179 Год назад +13

    Earths flat

  • @discovertheworldwithrio7836
    @discovertheworldwithrio7836 11 месяцев назад +1

    There is no Globe 👁️

  • @christophesutter1844
    @christophesutter1844 Год назад +2

    Analemm de mars ne s explique que par le geocentrisme et c est la vérité la terre est au centre de l univers. Amamen

    • @TheBasskult
      @TheBasskult Год назад

      Très intéressant! Je sais également que la terre est stationnaire et n'est pas un globe, mais en quoi l'analemme de mars est compatible avec la réalité géocentrique et non pas la théorie heliocentrique? J'aimerais comprendre l'argument, merci!:

  • @DanDan-j6f
    @DanDan-j6f Месяц назад

    There is no globe .... wtf

  • @adomadam
    @adomadam 4 месяца назад

    The earth is flat 100%

    • @luismarquez5047
      @luismarquez5047 Месяц назад

      An amoeba might have a higher IQ than you, if we're being honest. 😂😂😂