AST101H1 Lecture Notes - Lecture 12: Photon, 30 Foot Fall

• School: UTSG
• Department: Astronomy & Astrophysics
• Course: AST101H1
• Professor: Michael Reid

Document Summary

Lecture 12 - using spectroscopy to understand celestial objects. What is the energy of the emitted photon: less than that of the absorption because energy is required to make the jump. How many absorption lines would we see in the spectrum if we had many atoms with the energy. We can determine the makeup of faraway celestial bodies through these fingerprints. Movement towards us will result in smaller wavelengths, and away larger: moving towards = blue, moving away = red. This way we can tell the speed of moving objects. We can tell the speed of radial motion of objects. This is how we learned galaxies were moving farther away from us.