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The Astonomical Society of the Pacific (ASP) set up an outreach program in 1996 to teach Native American schoolchildren about astronomy. The ASP program provides teachers from the Navajo and Hopi nations with materials from astronomical research at Lowell Observatory in New Mexico. Lowell staff provided pictures of comets for school activities.

We observed a stellar occultation of the star U149 by Uranus from Lowell Observatory and the IRTF on Mauna Kea on November 6, 1998. The temperatures derived from isothermal fits to the Lowell lightcurves are 116.7±7.9 K for immersion, and 124.8±15.5 K for emersion. The secular increase in temperature seen during the period 1977–1983 has reversed. Furthermore, the rate of decrease (≥1.2 K/yr) cannot be explained solely by radiative cooling. Although the temperature structure of Uranus' upper atmosphere may be related to seasonal effects (e.g., the subsolar latitude) or local conditions (e.g., diurnally averaged insolation), these observations suggest nonradiative influences on the temperature, such as adiabatic heating/cooling or thermal conduction.

Observations of Triton were made using the Faint Object Spectrograph on the Hubble Space Telescope in August of 1995. We present a visual spectrum of Triton between 3000 and 8500 A˚. We compare our measurements with previous observations and find that Triton's color in 1995 is consistent with its color at the time of the Voyager 2 flyby.

On 22 May 1995, as the Earth crossed through Saturn's ring-plane, we used the Wide Field Planetary Camera 2 on the Hubble Space Telescope to image Saturn and its rings for 10 hr centered near the predicted time of ring-plane crossing. By performing photometry on the rings, we find that the time of ring-plane crossing is later than the nominal predicted time, suggesting that Saturn's pole is precessing at a rate somewhat slower than is predicted for a rigid body under the influence of torques from the Sun and Saturn's satellites and/or that Saturn's pole position is different from the nominal position. We determine the equivalent thickness of the rings to be 1.4 ± 0.1 km, and find that the measured value corresponds to the amplitude of perturbations from the Laplace plane warp and satellite-induced bending waves.

A 14th magnitude double star was occulted by 2060 Chiron on 1993 November 7. Observations of this event were obtained from five locations in California. An occultation by Chiron's nucleus was recorded at one of these sites, while a possible graze by the nucleus was seen at the next closest location. If this possible graze represents a true detection of the nucleus, Chiron's radius is determined to be 89.6 ± 6.8 km, assuming a circular outline for the shape. If the nucleus was not seen at the second location, Chiron's radius is only constrained as being greater than 90.2 ± 6.5 km. The presence of dust in Chiron's inner coma was also detected in four of the five occultation datasets. Lightcurve features were identified that may be explained by narrow, collimated jets of material, and by a much larger region of dust distributed asymmetrically about Chiron's nucleus. Periodic fluctuations in the dust may have been detected in one of the lightcurves. If this periodicity is real, and is induced as a result of Chiron's rotation, then a minimum expansion velocity for the dust is found to be ∼40 m sec−1.