AS101 Lecture Notes - Metallic Hydrogen, Solid Nitrogen, Galilean Moons
Document Summary
Moderately high orbital eccentricity (0. 206) meaning its orbit is observably elliptic. Orbital inclination is also high (7 degrees), greater than all others except pluto. Rotational axis tilt is 0 degrees; no seasons on mercury. Orbital period: 88 days, synodic period of 116 days (time between successive conjunctions with earth) The two elongations, eastern and western, are the greatest angular positions the inner planet ever has with respect to earth. The two conjunctions, superior and inferior, refer to when mercury is lined up with the earth and the sun. When the order is earth-sun-mercury, we have a superior conjunction and when mercury is between the sun and earth, we have an inferior conjunction. We might see a solar transit during an inferior conjunction. Not tidally locked to the sun; rotates one and a half times during each orbit. A solar day on mercury (sun rise to sun rise) is 176 earth days long (rotates very slowly)