Page:Description and Use of a New Celestial Planisphere.pdf/42

37 Stars, &c. their names and characters are as follow:—☉, the Sun, is in the center, and ☿, Mercury, is nearet to the Sun of all the Planets, and performs its coure round the Sun in about three months, or 87 days, 23 hours. ♀, Venus, whoe Orb is next to Mercury, revolves round the Sun in 224 days, and 17 hours, or about eight months. The Planet, which is the third in order from the Sun, is our Earth, performing its annual orbit in 365 days, 5 hours, and 49 minutes: the next is ♂ Mars, which moves round his Orb in 686 days and 23 hours. Then ♃ Jupiter, performs his circuit in 4332 days and 12 hours, or about 12 years. Then ♄ Saturn, completes his revolution in 10759 days, and 7 hours, or a little less than 30 years. Then the Georgian Planet, whose Orb is exceeding remote, and motion very low, as may be een in the Nautical Almanac. Thoe Planets, whose Orbs are beyond the Orb of the Earth, are called Superior Planets; but Venus and Mercury, whose Orbs are between the Earth's Orb and the Sun, are called Inferior Planets. The Georgian, Saturn, Jupiter, and the Earth, have their econdary Planets, or Satellites accompanying them round the Sun; and moving round them alo, in certain periods. Jupiter hath four, and the Earth one; which is the Moon, revolving round it in 27 days, 7 hours, and 43 minutes, which is alo the exact time of her rotation round her axis, o that he always turneth the ame ide, or part of her Surface towards us; her Orbit is an Ellipis, whose mean Radius is about 244258 miles, and whoe Plane is inclined to the Plane