This is the Web Edition of "A Trip Into Space", a Coimbra-based electronic book on space science. Both the texts and the photos are by courtesy of National Aeronautics and Space Administration. |
A Trip Into Space Uranus Uranus - In True And False Color | |
See also: Uranus Fact Sheet, Uranus Rings Fact Sheet, Uranus - False Color Image, Bright Cloud From 12.9 Million Km, Uranus - False-Color Image From 2.7 Million Km |
These two pictures of Uranus - one in true color (left) and the other in false color - were compiled from images returned on January 17, 1986, by the narrow-angle camera of Voyager 2. The spacecraft was 9.1 million kilometers (5.7 million miles) from the planet, seven days before its closest approach.
The picture on the right uses false colors and contrast enhancement to bring out subtle details in the polar region of Uranus. Images obtained through ultraviolet, violet, and orange filters were respectively converted to blue, green, and red colors to produce the picture. The very slight contrasts visible in true color thus are greatly exaggerated here. In this false-color picture, Uranus reveals a dark polar hood surrounded by a series of progressively lighter concentric bands. One possible explanation is that a brownish haze or smog, concentrated over the pole, is arranged into bands by zonal motions of the upper atmosphere.
Several artifacts of the optics and processing are visible. The occasional doughnut shapes are shadows cast by dust in the camera's optics; the processing necessary to bring out the faint features also brings out these camera blemishes. In addition, the bright pink strip at the lower edge of the planet's limb is an artifact of the image enhancement. In fact, the limb is dark and uniform in color.
The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Last Update: 2005-Nov-29