Explore spectra in two ways: first observe gases and stars visually, then compare a space spectrum directly above a lab reference to identify elements and spot redshift.
Choose a gas, light the discharge tube, then reveal its emission spectrum or absorption spectrum over the tube.
Select a space object, then reveal the absorption spectrum or emission spectrum seen through the telescope.
Pick a space observation and a lab reference. The space spectrum is shown directly above the lab spectrum. Use the slider to move the lab reference until the line pattern matches. A shift towards the red end shows redshift.