Hubble images revealed in April taken with WFPC-2 over a period of weeks in October and November 1994 show changing weather conditions on Neptune. Neptune's atmosphere changes over a matter of days. The Great Dark Spot seen by Voyager 2 in 1989 has gone away; its name is now "Great Dark Spot 1989." A new dark spot, called "Great Dark Spot 1994," is now visible in Neptune's northern hemisphere, a mirror image across the equator of the prior dark spot. Its image is much less clear than that taken from Voyager 2, but it does show; given Neptune's current tip away from Earth, it appears on Neptune's limb.
An infrared image taken at Mauna Kea on September 10/11, 1994, by Keith S. Noll, Diane Gilmore and David R. Soderblom at the NASA Infrared Telescope Facility. Filters between 1.2 and 2.2 microns were used. The images were taken with a 256x256 pixel infrared array called NSFCAM. The images appeared in Sky & Telescope for March 1995, p. 12. Clouds show on Neptune, which was only 2.3 arc sec across. Triton appears at upper left.photo courtesy K. Noll, D. Gillmore and D. Soderblom