PCS 181 Lecture Notes - Lecture 2: Radial Velocity, London Academy Of Music And Dramatic Art, Raisin Bread

• School: Ryerson University
• Department: Physics
• Course: PCS 181
• Professor: Margaret Buckby

Document Summary

Short wavelength: blue light/blue star that"s moving= blue shifting(moving closer to you peaks are squished) . whole pattern of hydrogen lines moved towards the blue in the spectrum. Long wavelength = red light/red shifted . moving away peak are further. Obtain spectrum of stationary (=not moving) source (e. g. hydrogen in the laboratory. Obtain spectrum of a moving object (e. g. a star) Diagram lab spectra emission spectrum compared to stellar spectrum (absorption) . lines in the star spectrum are shifted to the red side compared to the lab spectrum therefore its red shifted (moving away) Symbol delta lamda = wavelength difference between lab and stellar spectra. Symbol lamda = wavelength on lab spectrum. ***** on test for sure - radial velocity and if the star is moving away from you or towards you. If its shorter than lab wavelength, it is blue and towards you. H spectral line is *lamda = 656. 2850 nm in the lab . this is red wavelength.