Chromaffin cell. Chromaffin cells, also pheochromocytes, are neuroendocrine cells found mostly in the medulla of the adrenal glands (located above the kidneys) in mammals.
The elements sodium (Na) and potassium (K) have been detected in the Moon's atmosphere using Earth-based spectroscopic methods, whereas the isotopes radon -222 and polonium -210 have been inferred from data obtained by the Lunar Prospector alpha particle spectrometer.
The moon's synodic period of orbit around the earth is 29.53 days, roughly. This is the length of time it takes for the moon to reach the same position <i>relative to the sun</i> as the starting position. So the synodic period reflects the cycle of moon phases.