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 Cycle. The term moon cycle (or lunar cycle) refers to the moon's continuous orbit around the earth. As the moon orbits the earth, its appearance (the phase) changes and thus gives us an indication of the moon's progress in the cycle (the age).