On this day in 1797 – January 4th – German astronomer Wilhelm Beer was born.

Beer was an amateur astronomer, who with Johannes Heinrich Maedler, published the first map of the Moon (Mappa Salenographica). They also made a map of Mars and calculated the planet's rotation period to within 0.1 second of today's figure.


Mona Evans
For news, activities, pictures and more, sign up to the Astronomy Newsletter!

http://www.bellaonline.com/newsletter/astronomy