  Observations of the red giant Arcturus (Alpha Boo) obtained with the star
tracker on the Wide Field Infrared Explorer (WIRE) satellite during a baseline
of 19 successive days in 2000 July-August are analysed. The power spectrum has
a significant excess of power at low-frequencies. The highest peak is at about
4.1 micro-Hz, which is in agreement with the ground-based radial velocity and
photometry study of Belmonte et al. (1990a; 1990b). The variability of Arcturus
can be explained by sound waves, but it is not clear whether these are coherent
p-mode oscillations.
