Question: what is a spectroscopist? :D

Andrew Thomas answered on 25 Jun 2012:

Hi, A spectroscopist is someone who (usually) uses light to understand the world around us. The word light to a physicist includes everything from infrared through the visible region (the colours of the rainbow) to X-rays (in fact there’s a bit more as well as these). I use ultraviolet radiation and X-rays to look at the top few layers in a solid and we can work out how molecules stick to surface. We can also work out where electrons are in a solid. We look to see which bits of the light are absorbed and which are allowed through.
Try this experiment: Get some red food dye and some green food dye then shine a red laser pen through them (if you have one). What do you find? This tells us that one of the food colourings absorbs the red light and, since light is energy, it has been transferred. It is actually transferred to electrons in the atoms. The other food dye lets the red laser straight through so we can’t excite the electrons with the red laser and it passes through without being absorbed.
Astronomers use spectroscopy to look at stars and from this they can tell what the stars are made of.
My colleague who is also a spectroscopist uses light to look at skin of frogs and humans. In fact, if you have ever been in hospital and had one of those little clips on your fingers that glow red the nurse is doing spectroscopy of your blood to see how much oxygen there is in your blood.