Illustration taken from 'Uranometria' (1603) by Johann Bayer, showing the zodiacal constellation of Gemini (the Twins). German astronomer and lawyer Johann Bayer (1572-1625) invented the system for naming stars using letters from the Greek alphabet, a system still used today for the brighter stars - those visible to the human eye without the aid of a telescope. 'Uranometria' depicts the positions of nearly 1000 stars in addition to those identified by Tycho Brahe. Gemini gets its name from the two bright stars within it, Castor and Pollux. Gemini is also interesting astronomically because one of the most prominent meteor showers, the Geminids, radiates from the constellation, peaking in intensity on 13th-14th December each year.
© Science Museum / Science & Society Picture Library