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Definition of Astronomical Dawn

-- Omar | May 9, 2020

Question:

Can you please confirm whether astronomical dawn always begins at 18 degrees, regardless of location and time of year?

Thank you,

Omar

-- Omar

Answer:

Yes, astronomical dawn is defined as the time when the geometric center of the Sun is at 18 degrees below the horizon in the morning, when the Sun is rising.

-- Jeff Mangum

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