The observation protocols of Tycho Brahe hold the astronomic observations which Tycho and his assistants made from 1563, when Tycho was 16 years old, until his death in 1601.
The pages shown here (127 recto - 137 recto) are from the volume which comprises the period January 1st 1596 - October 20th 1587.
GKS 316 2º, paper, 208 ff.; 34,5 x 20 cm. *Denmark 1596.
See also the virtual exhibition of The Royal Library: The astronomical Instruments of Tycho Brahe.