Physics
Spectroscopic Techniques
Quick fact
When a gas is heated, it emits light only at specific colors (wavelengths), creating a unique 'fingerprint' for each element—this is how helium was discovered on the Sun before it was found on Earth.
Why this is interesting
You've seen rainbows and know white light splits into colors—but did you know that the dark lines in the Sun's spectrum tell us what elements it's made of? How can a simple beam of light reveal so much about distant worlds and tiny molecules?