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 is the second densest satellite in the Solar System after Io. However, the inner core of the Moon is small, with a radius of about 350 km (220 mi) or less, around 20% of the radius of the Moon.