How to read it
Surface temperature in kelvin decreases from left to right by convention. Luminosity is a logarithmic ratio in which the Sun equals 1. Hover over a point for the name, editorial class label and stage.
Data Lab
Star Classification Lab
How do temperature and luminosity place a few familiar stars on a simplified Hertzsprung-Russell diagram?
Loading the downloadable CSV...
CSV schema
name; temperature_k in kelvin; luminosity_solar as a ratio to the Sun; and editorial class and stage labels. The chart reads these exact rows at load time.
Limits
This five-object table was assembled by the site for teaching. It is not a Gaia export, population sample, or classification model. Values are rounded, uncertainties and extinction are omitted, and “DA” is a white-dwarf spectral label rather than an ordinary OBAFGKM class.
Try it yourself
Lab task
Locate the Sun and Sirius B. Describe their positions using only the two plotted measurements, then list the extra spectrum or uncertainty information needed before assigning a formal class.
Signal interpretation console · data labs
Star Classification / observation pipeline
Photons
Identify wavelength, exposure, field of view and observing date before reading the image.
Detector
Separate object signal from point-spread function, noise, saturation and selection.
Calibration
Track background removal, alignment, scaling and color mapping as part of the measurement.
Physical claim
Connect “Understanding Star Classification” to “Stellar Evolution & Lifecycle” through an explicit model.
PRIMARY READOUT
Explore the distribution of different star types in our galaxy and understand how stellar classification reveals the diversity of cosmic objects.
MODEL WARNING
Color, spectrum, luminosity and evolutionary state are related but not interchangeable; distance and extinction shape where an object appears in a diagram. Projection, distance, extinction or adopted parameters may offer another explanation.
CROSS-CHECK
Query ESA Gaia Data Release 3 and seek an independent wavelength, spectrum, motion or catalogue measurement.