is why it could not be seen in Galileo’s telescope. The original aspect was seen again in the years following 1613, but Galileo was never able to interpret it correctly. Various strange theories were proposed to explain the planet’s unusual form. Hevelius of Danzig, for example, believed Saturn to be elliptical in shape, with two “appendages” attached to the surface.The problem was solved by a Dutch astronomer, Christian Huygens, who began his observations in 1655. The telescopes that he used were much more powerful than Galileo’s, and gave a sharper defintion, so in a short time he concluded that “ Saturn is surrounded by a thin, flat ring which nowhere touches the body of the planet.” His theory was not widely excepted, but by 1665 it had been universally accepted, even though the nature of the ring system was not established until much later. Data for Saturn are given in table one on the next page. Table 1: Planetary Data For SaturnDistance from the Sun Mean 9.54 a.u. (1,472,000,000 km)Maximum 10.07 a.u.Minimum 9.01 a.u.Sidereal period of revolution10,759.20 days, or 29.26 yearsMean synodic period378.1 daysRotation period(means)10 hours 39 minutes 24 secondsMean orbital velocity9.6 km/sec.Axial inclination26 44’Orbital inclination to the elliptic2 29’22”Orbital eccentricity0.056Diameter (equatorial) (polar)120,660 km108,000 kmApparent diameter seen from EarthMaximum 21”Minimum 15”Mass (Earth=1)95.17Volume (Earth=1)744Density (water=1)0.7Albedo0.61Satellites15Among planetary orbits, that of Saturn is of fairly low eccentricity (0.056), though the difference in distance between perihelion (closest approach to the Sun) and aphelion (farthest retreat from the Sun) amounts to 160,000,000 kilometers. Because Saturn is so far from the Sun and the Earth Saturn always appears to be full, or nearly so, in the sense of the full moon.The mean synodic perio...
