Wednesday, March 30, 2022

SearchResearch Challenge (3/30/22): Where is the oldest solar observatory in the Americas?

We all watch the sun... 

... sometimes with sunscreen, but nearly always at sunrise and sunset.  We notice when the days grow shorter or longer, and as we've seen in earlier SRS Challenges, it's an endless source of fascination for people, shadows, and the time of year.  

Since we've talked about the patterns that the sun makes in the sky, it got me to wondering, when did people first start keeping track and building observatories?  We know that Stonehenge, those marvelous circles of stone and ridges of earth in England, was built between 3000 and 1520 BCE.

What about the New World?  When did similar things start here? 

That's today's Challenge--can you find out? 

1.  When was the first observatory for sun-watching purposes created in the Americas?  Can you find out who made it?  Where is it?  And what happened to those people?  

This Challenge isn't hard, but when I found the answers, I was a bit surprised.  And naturally, once I started learning about these things, this led to further questions as I followed my curiosity a bit.  

I'm curious now: What else did you find interesting to seek out?  What did this Challenge prompt you to go learn about?  

Curious is as curious does.  Where does all this take you?  

Tell us your stories in the comments below. 

Happy observing! 

Search on! 


  1. This was interesting. I found out that the first observatory in in Peru and called Chankillo. So interesting that Stonehenge is so well known and yet I've never heard of Chankillo. I now would like to know more about the people who created this. If they were so advanced that they were able to create something like this what happened to them. This article was fascinating-

  2. My first thought was Mexico's Chichen Itza. Not as the first or oldest but as an observatory.

    With a quick search, that needs to go deep, found

    [first observatory americas]

    Chankillo in Peru

    With [list of ancient observatory americas]

    Amazing observatories of the ancient world

    And, reading that, last week read about Machu Picchu this:Huayna Picchu?

    1. Virtual Chankillo

    2. More about Chankillo. Who built it unknown but mentions what happened to that culture

      In Mexico:

      La ciudad prehispánica de Pahñú era un observatorio solar

      Cholula:La pirámide más grande del mundo por su volumen, la gran pirámide de Cholula, está orientada a la puesta solar en el día del solsticio de verano. No sólo la pirámide, sino también la traza de la ciudad, la prehispánica y la actual, señalan en esa misma dirección. Source:

      Cholula in 1885 (photography)

      And, unrelated but interesting wood spoon. How it is made? (Video)

    3. Another list of: List of archaeoastronomical sites by country ( Wikipedia)

  3. …where staring at Sun led me…
    a newer one, New Mexico
    solar/galactic crime?… probably less of an issue at Chanquillo or Chankillo?, but who knows, different internet
    and search engines back then…

    what's the old saying — "sunlight is the best disinfectant"
    James Bryce in his 1888 book, The American Commonwealth.
    quote mining
    were they looking for CMEs? hydrogen into helium… 100 M degrees…
    UNESCO - the 10 day week
    from the Nile side:
    "When I open my eyes there is light; when I close them there is thick darkness. My secret name is known not unto the gods. I am Khepera at dawn, Ra at high noon, and Tum at eventide."
    Chankillo time: (I always thought it was a music festival in SoCal… but Goo deprives me of such blissful ignorance…)
    "If the Gospel of Matthew is historically accurate, this would mean that Jesus of Nazareth was born on or before 4 BCE—meaning Jesus was born 4 BC (4 years Before Christ)!"

  4. Just did a quick search for first sun observatory in the Americas and was directed to: and was surprised to learn about the Chankillo civilization that built the first sun observatory, in the middle of the first millennium BCE, which preceded the better known civilizations in South and Central America. The observatory consists of a sequence of 13 stone towers, and measures the progress of the year, with the sun to left of the first tower on the summer solstice, to the left of the last on the winter solstice, and dead in the middle at the equinoxes. All of this was new and surprising to me and my family.

  5. a virtual tour
    off topic, but what is this - it won't render for me…

  6. Since I have been fascinated by astronomy since I was a little girl I jumped into this one.

    [first observatory Americas] yielded
    which apparently was the first professional observatory in the Americas (I left “solar” out of my search); interesting but not to the point.

    Then I found the resources others had found plus

    which gave a detailed description of the observatory.

    I wanted to learn more about the people who built this structure, and why, and what STEM knowledge they needed, the science and psychology of it.

    The search [people chankillo]
    gave some Youtube videos and

    This latter web site leads to 3299 audio episodes of “Engines of our Ingenuity” (complete with transcripts) which seeks to learn “how inventive minds work”. This will provide me with many hours of enlightening digression. If you believe that science helps us deal with the foolishness of life, you will love this.

    Then I went further afield and learned about Sir Brunel and an amazing fact from number theory, as well as memories of Stonehenge and its knockoff at Maryhill.

    I too was surprised that I have never heard of this observatory. I recently took a virtual trip to Peru and cannot find a reference to it in my notes. I believe the reason is because it is so overshadowed by Machu Picchu and the Incan civilization. I wonder why. Someone once told me, in a different geographical context, that it’s all in the marketing.

  7. thanks to Ramón and Mathlady for the links - they will take some time - wiki list of archaeoastronomical sites & Engines of our Ingenuity, respectively.
    Dan makes it out to CO., now and then… a sidetrip?:
    lunar standstill
    a stitched Sun observation
    from ML's EoOI point:
    2754 - data mining Google, right up Dan's alley, linguistics involved too
    contributor - Kresimir Josic, seems on hiatus
    Krešimir Josić, UoH page
    on the twitter thing
    2928 - the quote: ' it’s tough trying to peer over an edge that isn’t there.'
    (initially read it as '' it’s tough trying to pee over an edge that isn’t there.'', 1/2 right, but all wrong - thought it conveyed the sentiment as well… meh)

    1. Thanks to you, Remmij. You are always providing us with interesting, different and curious links.

      Do you know where the stitched Sun was taken? It's is beautiful. I saw once an archaeoastronomical photo made with Popocatépetl. I can't find it online. (I saw it in a Park in a special exhibition)

      Also thanks for Kresimlr Twitter. He posted a tweet with a beautiful Snoopy. Besides his regular posts that I will read.

      Out of topic. And related, of course, with Search and Google, read this about how in-depth Search and AI is used for vulnerable users. I read, the important information in Google Blog too. (In case you want to read in English)

  8. I did not know that… or gnocchi that - it comes from bushes…
    more detail
    1978, San Giorgio

  9. [the first observatory for sun-watching purposes created in the Americas] finds
    Science Alert is a reliable and accurate site IMHO
    Questions arising:
    How did they handle the time change for Daylight Savings? Heavy lifting?
    Did they build this just because they could and already knew how?
    Did they think their stones controlled the sun positions?
    Why did they need to know the date?
    They must have had a pretty accurate notion of making/naming the 'days' and know how many days were in a 'year'
    That's the big mystery isn't it; that such a sophisticated society could vanish without apparently a trace.
    Why didn't take their calendar/clock with them when they left?
    Was there a lot of blindness? From staring at the sun. has this comment: Anthony Aveni, an archeoastronomer at Colgate University, agrees with Ghezzi's interpretation that the site is of great cultural, religious and political significance, in addition to its practical use for timing plantings and harvests. Ghezzi excavated the site.
    By catch to this was learning the explanation of wiffle ball physics from the npr site.
    Good one.