AAS Random Astro-Facts

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AAS Random Astro-Facts

Thanks to the American Astronomical Society, throughout Global Astronomy Month, we will be featuring a Random Astronomy Fact everyday! Come back daily or tune into our social media channels to find out what is the fact of the day!

Maximum possible diameter of Moon's umbra on Earth: 170 miles. On August 21st, ~70 miles.

Moon's shadow has two parts: umbra (Sun blocked fully) and penumbra (Sun blocked partially).

In total solar eclipse, Moon's shadow falls on Earth, moving very fast roughly west to east.

In total solar eclipse, Moon completely covers Sun's bright face, revealing solar corona.

Thanks to cosmic coincidence, Moon and Sun appear roughly the same angular size in our sky.