Pan (moon)

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Pan
Pan side view.jpg
Pan amid the rings of Saturn. The 'side' view gives Pan the appearance of being embedded in the rings, although it actually travels within the Encke Gap.
Discovery
Discovered by M. R. Showalter
Discovery time July 16, 1990
Names
Adjective Pandean
Orbit[1]
Longest distance from the center of its orbital path
("semi-major axis")
133,584.0±0.1 km
How egg-shaped its orbit is
("eccentricity")
0.0000144±0.0000054
How long it takes to complete an orbit 0.575050718 days (13.801217 hours)
Angle above the reference plane
("inclination")
0.0001°±0.0004°
What it orbits Saturn
Size and Other Qualities
Measures 34.4 × 31.4 × 20.8 km
Average distance from its center to its surface 14.1 ± 1.3 km[2]
Mass 4.95 ± 0.75 ×1015 kg[2]
Average density 0.42 ± 0.15 g/cm³[2]
Gravity at its surface 0.0001–0.0018 m/s2
Slowest speed able to escape into space
("escape velocity")
~0.006 km/s
How long it takes to turn around one time synchronous
Angle at which it turns
(in relation to its orbit)
zero
How much light it reflects 0.5
Avg. surface temp. ~78 K
Pan viewed through the rings (Cassini)

Pan is a moon of Saturn. It is the closest moon to the planet, orbiting 133,600 km above Saturn's cloud tops. It was discovered in 1990 by Mark Showalter. He discovered Pan when he was analysing the photos taken by Voyager 2.[3] It orbits inside the Encke gap of Saturn's A Ring.

Pan was named after the Greek god Pan on 16 September 1991.[4] It is also known as Saturn XVIII.[5]

Its mass is in the range 4.95 \pm 0.75 \times 10^{15} kg.[6]

References[change | change source]

  1. Jacobson, R. A.; et al. (2008). "Revised orbits of Saturn's small inner satellites". Astronomical Journal 135 (1): 261–263. doi:10.1088/0004-6256/135/1/261.
  2. 2.0 2.1 2.2 Thomas, P. C. (July 2010). "Sizes, shapes, and derived properties of the saturnian satellites after the Cassini nominal mission". Icarus 208 (1): 395–401. doi:10.1016/j.icarus.2010.01.025. http://www.ciclops.org/media/sp/2011/6794_16344_0.pdf.
  3. IAUC 5052: Saturn 1990 July 16 (discovery)
  4. IAUC 5347: Satellites of Saturn and Neptune 1991 September 16 (naming the moon)
  5. "Planet and Satellite Names and Discoverers". Gazetteer of Planetary Nomenclature. USGS Astrogeology. July 21, 2006. http://planetarynames.wr.usgs.gov/append7.html. Retrieved 2007-09-14.
  6. Sizes, shapes, and derived properties of the saturnian satellites after the Cassini nominal mission