It really is quite a wonderful feeling sharing knowledge with other people. Occasionally, I’ll take out the spectroscopy cart. Some people may remember their Chemistry classes when the teacher sent electrical charges through little gas tubes and then gave you a spectroscope or little glasses. In case anybody needs a refresher, what happens is that when you have a lot of energy the electrons in the atoms will jump to a higher level of orbit, and when they come back down they release photons of light at different wavelengths depending on how far the electron fell. The spectroscope or little glasses
function as a prism and break down the light released into the wavelengths which
it is being released at. If you have, say, Helium, you’ll see two red bars, a yellow bar, a turquiose bar, a blue bar, and an indigo bar. Every element has a different pattern of bars.
I like to start by asking them if they’ve ever wondered how we know what the stars are made of. Of course they wonder how we know. You can’t exactly go to one… they’re millions of light years away! But, if you look at the light they’re emitting through a spectroscope, you can look at the pattern of bars and tell what is inside. I’ll explain this to them, and turn on a hydrogen or helium gas tube and hold up a short chart of elements and their patterns to let them try to guess. With younger children, it’s pretty much just pretty lights and that’s fine, but older children, even adults, will often have
sudden moments of understanding.“That’s so cool…” they say, and they don’t just say it the way you say “that’s so cool” when your friend gets a new cell phone. When they say “that’s so cool” it’s almost as if there’s an entirely different definition because their voices are so saturated with awe and wonder. I suspect that they’re not just saying it because of the pretty lights, but as a
way of remarking about how amazed they are that they can understand it. I think that they’re remarking about how simple spectroscopy really is, and how cool
science is when you understand it with little effort.
I absolutely love hearing them say it and seeing their eyes light up. It feels like I should be thanking them as they walk away to their planetarium show.
