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Observations of the minute disks of Uranus and Neptune from the surface of the earth present a major challenge to any observatory site and require the most advanced techniques in optical imaging instrumentation. Less than 4 arcsec across, the disk of Uranus would fit within the Great Red Spot of Jupiter in the focal plane of a terrestrial telescope; the smaller disk of Neptune, less than 2.5 arcsec in diameter, is scarcely more than half again that of Ganymede, the largest of the Galilean satellites. At present, both planets are situated at far southerly declinations, making them even more difficult objects for Northern Hemisphere observatories.