Spectral Lines & Doppler Shift
This interactive simulator explores Spectral Lines & Doppler in Astronomy & The Sky. Absorption lines on a continuum shift with radial velocity (Δλ/λ ≈ v/c). Use the controls to change the scenario; watch the visualization and any graphs or readouts to connect the model with lectures, labs, and homework.
Who it's for: Best once you already know the basic definitions and want to build intuition. Typical context: Astronomy & The Sky.
Key terms
- spectral
- lines
- doppler
- spectral doppler
- astronomy
How it works
A star or galaxy moving away stretches wavelengths toward red; motion toward us compresses them (blue). Astronomers measure tiny shifts in known spectral lines to infer radial velocities and, for cosmology, redshifts.
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