Saturn's Satellite Pan

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Дата изменения: Sun Mar 15 05:20:59 1998
Дата индексирования: Sat Dec 22 09:32:26 2007
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Поисковые слова: annular

Pan
Saturn XVIII - 1990S18, 1981S13

Pan, the innermost known satellite, was found from photographs taken by Voyager during its encounter with Saturn. It was discovered by Mark R. Showalter in 1990, 9 years after the Voyager encounter. Pan is located 133,583 kilometers from the center of Saturn and is within the Encke Gap of Saturn's A-ring. It acts as a shepherd and is responsible for keeping the Encke gap open. It has a diameter of 20 kilometers.

Pan Statistics

Discovered by	Mark R. Showalter
Date of discovery	1990

Mass (kg)	?
Equatorial radius (km)	9.655
Equatorial radius (Earth = 1)	1.5138e-03
Mean density (gm/cm^3)	?

Mean distance from Saturn (km)	133,583
Rotational period (days)	?
Orbital period (days)	0.5750
Mean orbital velocity (km/sec)	16.90

Orbital eccentricity	0.00
Orbital inclination (degrees)	0.0

Visual geometric albedo	0.5
Magnitude (Vo)	?

Views of Pan

Pan
This image shows the small moolet Pan located within the Saturn's Encke gap. The contrast has been enhanced and the image has been sharpened. (Copyright © 1998 by Calvin J. Hamilton)

Pan Within Encke Gap
This is the highest resolution image of Pan from the Voyager data. This image shows the A ring entering Saturn's shadow. Pan is located in the center of the small box within the Encke gap. Pan is shown enlarged and enhanced in the inset box. (Copyright © 1998 by Calvin J. Hamilton)

References

Showalter, Mark R., "Visual detection of 1981S13, Saturn's eighteenth satellite, and its role in the Encke gap," Nature, Vol. 351, 27 June 1991, 709-713.

Saturn Atlas