How are we able to determine the composition of our orbiting planets?
Asked by: J.J. Yrue
Essentially we look at the light being reflected
from the planet. This is called spectroscopy
and it involves looking at the wavelengths of all
the photons that are coming from the planet. Each
element emits light at a characteristic wavelength
that can be determined in a lab here on earth.
so we just match up the wavelengths of incoming
light with the wavelengths we know, and then
determine the composition of the planet, and its
relative quantity of each element.
Answered by: Mike Perkins, Physics/Astronomy Major, Penn State
'I beseech you to take interest in these sacred domains so expressively called laboratories. Ask that there be more and that they be adorned for these are the temples of the future, wealth and well-being. It is here that humanity will grow, strengthen and improve. Here, humanity will learn to read progress and individual harmony in the works of nature, while humanity's own works are all too often those of barbarism, fanaticism and destruction.'