APOD
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
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” .
What was that?: Help identify a mystery flash seen on Mauna Kea
| Date | June 25, 2011 |
|---|---|
| Credit | Image Credit & Copyright: Elias Politis |
| Authors & editors: | Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |



