The rotation of Uranus

A historical review of the use of three independent techniques for measuring the rotational rate is presented. The approaches examined are: (1) using theoretical interior models together with observations of the oblateness and the gravitational moment; (2) studying periodic fluctuations in the brightness; and (3) spectrographically measuring the Doppler shifts (line tilts). Measurements of line tilts obtained using the Kitt Peak National Observation 4 meter telescope with a Cassegrain echelle to high obtain high spectral dispersion and large image are discussed and compared with results obtained by Muench and Hipplelein (1980) and by Hayes and Belton (1977). The possibility of using speckel imaging techniques to detect the motion of features across the disc in the 6091 methane band, and with more suitable image intensifiers, in the 7261 band is considered.