From: Van L <van@scratch.space>
To: Help Gnu Emacs mailing list <help-gnu-emacs@gnu.org>
Subject: Re: Wrong times for sunrise/sunset?
Date: Sat, 26 Jan 2019 13:02:44 +1100 [thread overview]
Message-ID: <98706E3F-46B2-4C90-AC52-D839434F3BEA@scratch.space> (raw)
> (I understand that I know very little abot time calculations and such,
> and I understand they are difficult. I'd just like to know.)
Metwo.
Can those calculations tell the diameter of the Sun? without; observation.
In his astronomical writings, Proclus described how the
water clock invented by Heron could be used to measure the
apparent diameter of the Sun. Proclus's method can be used
at the equinox. Water is collected from the clock in a
container while the sun rises. As soon as the Sun has risen
the water is collected in another container and this
measurement continues until sunrise the following day. Then
the ratio of the weights of water in the two containers
gives the apparent diameter of the Sun. [1]
Footnotes
─────────
[1] The link is:
<http://www-history.mcs.st-and.ac.uk/Biographies/Proclus.html>
next reply other threads:[~2019-01-26 2:02 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-26 2:02 Van L [this message]
-- strict thread matches above, loose matches on Subject: below --
2019-01-19 19:17 Wrong times for sunrise/sunset? Pierpaolo Bernardi
2019-01-20 5:38 ` Marcin Borkowski
2019-01-19 15:25 Marcin Borkowski
2019-01-20 5:52 ` ken
2019-01-20 6:10 ` Marcin Borkowski
2019-01-20 7:17 ` Bob Proulx
2019-01-24 17:04 ` Marcin Borkowski
2019-01-20 15:00 ` Óscar Fuentes
2019-01-24 17:01 ` Marcin Borkowski
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