by APOD Robot » Sat Jun 25, 2011 4:08 am
Eclipse over the Acropolis
Explanation: The total phase of the
June 15 lunar eclipse lasted an impressive 100 minutes. Its entire duration is covered in this composite of a regular sequence of digital camera exposures, tracking the dark lunar disk as it
arced above the Acropolis in Athens, Greece.
In fact, around 270 BCE Greek astronomer
Aristarchus also tracked the duration of lunar eclipses, though without the benefit of
digital clocks and cameras. Still,
using geometry, he devised a simple and impressively accurate way to calculate the Moon's distance, in terms of the radius of planet Earth, from the eclipse duration. A more modern Greek astronomer, Elias Politis titled this eclipse duration study and the accompanying youtube timelapse
video "Acropoclipse".
[/b]
[url=http://apod.nasa.gov/apod/ap110625.html][img]http://apod.nasa.gov/apod/calendar/S_110625.jpg[/img] [size=150]Eclipse over the Acropolis[/size][/url]
[b] Explanation: [/b] The total phase of the [url=http://apod.nasa.gov/apod/ap110617.html]June 15 lunar eclipse[/url] lasted an impressive 100 minutes. Its entire duration is covered in this composite of a regular sequence of digital camera exposures, tracking the dark lunar disk as it [url=http://apod.nasa.gov/apod/ap110320.html]arced above the Acropolis[/url] in Athens, Greece. [url=http://eclipse.gsfc.nasa.gov/LEhistory/LEhistory.html]In fact[/url], around 270 BCE Greek astronomer [url=http://www-groups.dcs.st-and.ac.uk/~history/Mathematicians/Aristarchus.html]Aristarchus[/url] also tracked the duration of lunar eclipses, though without the benefit of [url=http://itotd.com/articles/297/revenge-of-the-analog-clock/]digital clocks[/url] and cameras. Still, [url=http://www.phy6.org/stargaze/Shipprc2.htm]using geometry, he devised[/url] a simple and impressively accurate way to calculate the Moon's distance, in terms of the radius of planet Earth, from the eclipse duration. A more modern Greek astronomer, Elias Politis titled this eclipse duration study and the accompanying youtube timelapse [url=http://www.youtube.com/watch?v=kOXR1ga1UlE]video "Acropoclipse"[/url].
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