APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

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APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby APOD Robot » Sat Aug 12, 2017 4:09 am

Image A Day in the Life of a (mostly) Human Sundial

Explanation: Have you ever wanted to be a gnomon? Of course, a gnomon is the tall part of a sundial that casts a shadow. The gnomon's shadow moves as the Sun moves across the sky, indicating time by the shadow's position on the dial face. So on July 19th, the Astronomy Group of the Progymnasium Rosenfeld created a human sundial, each participant patiently playing the role of the gnomon for 10 minutes. In this timelapse video of their temporal voyage of discovery, one image was taken every 20 seconds from 8 am until 4 pm Central European Summer Time. Drawn on the ground are the dial hour marks calculated to show the local time for that specific date. Behind, the tower clock offers a time check. Can you find the local time of solar noon? (Hint: At solar noon the Sun is on the meridan.) The persistent group plans a repetition of the human sundial performance next winter to compare the length of the day and the altitude of the Sun.

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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby Boomer12k » Sat Aug 12, 2017 7:02 am

Um... shouldn't it be away from buildings... er... in the sunlight???

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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby Ann » Sat Aug 12, 2017 7:45 am

Boomer12k wrote:Um... shouldn't it be away from buildings... er... in the sunlight???

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Boomer, you play a unique role here at Starship Asterisk*. If no one else chimes in to comment on the APOD, you do! :clap:

Good point, by the way. A sundial, including its gnomon, should be in the sun.

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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby Ann » Sat Aug 12, 2017 7:49 am

Boomer12k wrote:Um... shouldn't it be away from buildings... er... in the sunlight???

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Boomer, you play a unique role here at Starship Asterisk*. If no one else chimes in to comment on the APOD, you do! :clap:

Good point, by the way. A sundial, including its gnomon, should be in the sun.

Nevertheless, as a teacher, I must say that the students probably had fun and learned something, too. (But this experiment probably isn't the best way to teach youngsters that the Earth revolves around the Sun, not the other way round.)

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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby Boomer12k » Sat Aug 12, 2017 7:58 am

Ann wrote:
Boomer12k wrote:Um... shouldn't it be away from buildings... er... in the sunlight???

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Boomer, you play a unique role here at Starship Asterisk*. If no one else chimes in to comment on the APOD, you do! :clap:

Good point, by the way. A sundial, including its gnomon, should be in the sun.

Nevertheless, as a teacher, I must say that the students probably had fun and learned something, too. (But this experiment probably isn't the best way to teach youngsters that the Earth revolves around the Sun, not the other way round.)

Ann


Actually, Ann... I should have watched the video... but I thought it was only a picture... Stupid me.... I am sure they had fun and are learning a lot!!!!
It shows that Time is often an observation of movement...

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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby heehaw » Sat Aug 12, 2017 9:28 am

Well, they do say "gnomon is an island," don't they?

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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby De58te » Sat Aug 12, 2017 10:03 am

The first man was the tallest because his shadow can be seen peeking over the roof's shadow at 8:05 am (by the clock on the building). That's the best I could stop the video with my reflexes, but 5 minutes after 8 is close enough. You can extrapolate and draw the line from the peak of his head's shadow towards the base of the sundial. You don't need the base of the sundial to be in sun since you assume the people are standing perfectly vertical.

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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby JohnD » Sat Aug 12, 2017 11:08 am

How "Can you find the local time of solar noon? (Hint: At solar noon the Sun is on the meridan.)" ?

It's when the Sun is highest, so shortest shadow, but the gnomons (which sounds just WRONG! "Gnomoi"?) are all differemt heights.
The image of the sun in the video disappears off the top of the frame, so no help there.
Is the square built on a North/South axis? So the bricks are so aligned? In which case "XII" is about twenty degrees off which cannot be!

How "Can you find the local time of solar noon?"
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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby neufer » Sat Aug 12, 2017 11:13 am

heehaw wrote:
Well, they do say "gnomon is an island," don't they?

The Starship Asterisk* : to boldly go where gnomon has gone before.
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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby neufer » Sat Aug 12, 2017 11:21 am

Ann wrote:
... as a teacher, I must say that the students probably had fun and learned something, too. (But this experiment probably isn't the best way to teach youngsters that the Earth revolves around the Sun, not the other way round.)

Many of them spun around their axis ... which may have been the axial lesson.
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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby Ann » Sat Aug 12, 2017 1:42 pm

neufer wrote:
heehaw wrote:
Well, they do say "gnomon is an island," don't they?

The Starship Asterisk* : to boldly go where gnomon has gone before.


:lol2:

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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby Ann » Sat Aug 12, 2017 1:42 pm

neufer wrote:
Ann wrote:
... as a teacher, I must say that the students probably had fun and learned something, too. (But this experiment probably isn't the best way to teach youngsters that the Earth revolves around the Sun, not the other way round.)

Many of them spun around their axis ... which may have been the axial lesson.


Good point! :ssmile:

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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby Uhyerp » Sat Aug 12, 2017 2:42 pm

neufer wrote:
heehaw wrote:
Well, they do say "gnomon is an island," don't they?

The Starship Asterisk* : to boldly go where gnomon has gone before.


Dog was definitely gnomon

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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby neufer » Sat Aug 12, 2017 3:25 pm

Uhyerp wrote:
neufer wrote:
heehaw wrote:
Well, they do say "gnomon is an island," don't they?

The Starship Asterisk* : to boldly go where gnomon has gone before.

Dog was definitely gnomon

Wherefore dog was joined to tether, let gnomon put a sundial.
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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby Jim Armstrong » Sat Aug 12, 2017 4:00 pm

A great APOD, approaching classic status!
Made me smile a lot with laughs mixed in.

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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby FLPhotoCatcher » Sat Aug 12, 2017 4:17 pm

JohnD wrote:...the gnomons (which sounds just WRONG! "Gnomoi"?)...
John

Is it "Gnomoi" or "Gnomons"?
It's a debate for the future, for sure.
What's harder, Everest or Olympus Mons?
Who determines our nomenclature?

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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby neufer » Sat Aug 12, 2017 6:33 pm

JohnD wrote:
How "Can you find the local time of solar noon?
(Hint: At solar noon the Sun is on the meridan.)" ?

Is the square built on a North/South axis?

So the bricks are so aligned?
In which case "XII" is about twenty degrees off which cannot be!

(UTC + 1 hours) = Central European (i.e., Scandinavian 15°E local) Time

(UTC + 35 minutes) = local time for Rosenfeld, Germany : 8.724°E

APOD Robot wrote:
one image was taken every 20 seconds from 8 am until 4 pm Central European Summer Time. Drawn on the ground are the dial hour marks calculated to show the local time for that specific date. Behind, the tower clock offers a time check. Can you find the local time of solar noon? (Hint: At solar noon the Sun is on the meridan.)

Drawn on the ground are the dial hour marks calculated to show Central European [Standard/tower clock] Time :?:
Last edited by neufer on Sat Aug 12, 2017 7:39 pm, edited 2 times in total.
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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby E Fish » Sat Aug 12, 2017 6:36 pm

Gnomon is a Greek word. And the plural would be gnomones.

What I'm wondering is who randomly brought a skeleton to the town square. ...or does he just make a visit every day?

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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby Ann » Sat Aug 12, 2017 7:17 pm

E Fish wrote:Gnomon is a Greek word. And the plural would be gnomones.

What I'm wondering is who randomly brought a skeleton to the town square. ...or does he just make a visit every day?


When I went to Malmö Latinskola in the 1970s, we had a school skeleton to be used during biology classes.

Perhaps the skeleton in this video is the school skeleton of Progymnasium Rosenfeld?

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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby FLPhotoCatcher » Sat Aug 12, 2017 7:52 pm

E Fish wrote:Gnomon is a Greek word. And the plural would be gnomones.

According to sites wordhippo and isplural, gnomons is the plural.

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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby Chris Peterson » Sat Aug 12, 2017 8:01 pm

E Fish wrote:Gnomon is a Greek word. And the plural would be gnomones.

In this case, gnomon is an English word, with the regular English plural form, gnomons. The etymological origin of the word is irrelevant. (And in any case, we imported it from Latin, not Greek; if you insist upon foreign plural forms, you might as well go with Latin- gnomonae?)
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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby JohnD » Sun Aug 13, 2017 8:28 am

This strikes at the root of the wonderful ability of English to adopt and accommodate non-English words. This has endowed English with the largest vocabulary, and the freest grammar of any language. Chris, when you are required to supervise a number of postgraduate students, you deal with their theses, not thesises, which no doubt contain appendices, not appendixes. The work deals with data, not datums, and they will do so according to a group of criteria, not criterion's.

It is a concession to mediocrity that pages like this are forums, not forae, and we should not be afraid of acknowledging the non-English origin of English words. To impose a strict pluralisation rule on them would begin to put a straightjacket on the freedom of English.

Speak the speech, I pray you, as I pronounced it to you, trippingly on the tongue!

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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby Chris Peterson » Sun Aug 13, 2017 12:53 pm

JohnD wrote:This strikes at the root of the wonderful ability of English to adopt and accommodate non-English words. This has endowed English with the largest vocabulary, and the freest grammar of any language. Chris, when you are required to supervise a number of postgraduate students, you deal with their theses, not thesises, which no doubt contain appendices, not appendixes. The work deals with data, not datums, and they will do so according to a group of criteria, not criterion's.

It is a concession to mediocrity that pages like this are forums, not forae, and we should not be afraid of acknowledging the non-English origin of English words. To impose a strict pluralisation rule on them would begin to put a straightjacket on the freedom of English.

We pluralize by convention, not by etymology. Thus we now have "appendixes" as equally, perhaps more common then "appendices". Things tend to normalize over time. Which is a good thing. My rule is simple: use the normalized plurals whenever they are well accepted forms. (Sometimes there are interesting special cases, as with "datum"; both "data" and "datums" are accepted plural forms, but the are used to emphasize different contexts- not unlike "media" and "mediums".)

In some cases- as with "gnomon"- there is only one accepted plural form, which is the conventional -s.
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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby E Fish » Sun Aug 13, 2017 1:33 pm

I wasn't intending to start a debate about it. Someone asked and I answered. Yes, it can be given the English plural with no problem. Generally, one doesn't speak of more than one gnomon anyway. In my dictionary, there were few references to the word being used in the plural form. The reason I chose the Greek is because that is where it started (to my knowledge), and I disagree that etymology is irrelevant. Even if the word is anglicized, the origins of the word still matter and sometimes, we have imported a word wholesale, including the different forms. Interestingly, though, when I was looking it up in real dictionaries, they didn't list the plural at all.

Regardless, I wasn't intending to turn this into something to argue about. My apologies.

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Re: APOD: A Day in the Life of a (mostly)... (2017 Aug 12)

Postby Chris Peterson » Sun Aug 13, 2017 1:36 pm

E Fish wrote:Regardless, I wasn't intending to turn this into something to argue about. My apologies.

This is a forum that has entertained many interesting discussions about language over the years. Discussions, not arguments. No apology necessary!
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