Questions: What is a continuous spectrum? What is a bright line spectrum? What is a dark line spectrum? What does the spectrum tell you about the Sun? What does the bumper sticker mean? If the background on this bumper-sticker appears red, you’re going way too slow!

Spectroscope Separates light into a wide spectrum of colors.

Most of what is known about stars comes from spectral studies. There are 3 kinds of visible spectra: Continuous Bright-line Dark-line

Continuous Spectrum – unbroken band of colors from a source sending out all visible wavelengths.

Continuous Spectrum - can come from a (hot) glowing solid, a glowing liquid or a glowing gas (star).

Bright-line Spectrum – also called an emission spectrum, is a series of unevenly spaced lines of different colors and brightness. Hydrogen emission spectrum Sd

Bright-line Spectrum - Every element has its own unique bright-line spectrum, like a fingerprint. Helium emission spectrum s

Bright-line Spectrum are created by… Florescent lights

Bright-line Spectrum are created by… Northern & Southern lights

Bright-line Spectrum are created by… Nebula

Dark-line Spectrum – a continuous spectrum with dark lines where light has been absorbed. (absorption spectrum) Helium absorption spectrum

Dark-line Spectrum Are produced by stars.

Dark-line Spectrum The dark lines are in the exact same place as the bright lines would be for the same element in a bright-line spectrum. Helium absorption spectrum

Dark-line Spectrum The dark lines are formed when light passes through a cooler gas. The dark lines tell us what gases are in the atmospheres of stars and planets. Helium absorption spectrum

Stars’ (dark-line) spectra. Bright-line spectrum Hydrogen emission spectrum Stars’ (dark-line) spectra. Blueshift Redshift

Periodic Table & Spectrum

Hydrogen & Emission Spectrum

Hydrogen & Absorption Spectrum

Helium & Emission Spectrum

Helium & Absorption Spectrum

Fraunhofer Lines https://www.youtube.com/watch?v=eSMhVDQtPD4

To Do Today Complete page 1 before class on Monday. Read through rest of packet. So you know what we will be doing on Monday.