Science
Star Classification Card
Used by developers, writers, and creators worldwide.
A star classification card generator introduces the spectral classes that astronomers use to sort stars — the famous O, B, A, F, G, K, M sequence — each with its colour, temperature, and a real example. Stars are classified mainly by their surface temperature, which determines their colour, and this scheme underpins much of how we understand the night sky. This tool pairs each class with accurate details and a well-known example star, so the picture is both correct and memorable. Generate a card, learn the class, and connect it to a star you can name. It is ideal for astronomy students, stargazers, and science enthusiasts. Every class is matched with its true colour, temperature range, and example, so you can rely on it. Our own Sun sits comfortably in the middle as a G-type star.
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How to use
- Choose your options above
- Click Generate
- Copy your result
Detailed instructions
- Click Generate to produce a star class card.
- Learn its colour, temperature, and example.
- Connect it to a star you can name.
- Generate again for another class.
Use Cases
- •Learning stellar spectral classes
- •An astronomy lesson or revision
- •Stargazing reference
- •Quizzing yourself on star types
- •Connecting star colours to temperature
Tips
- →Order classes O, B, A, F, G, K, M.
- →Blue is hottest; red is coolest.
- →The Sun is a G-type star.
- →Colour reveals surface temperature.
FAQ
how are stars classified
Mainly by surface temperature, which sets their colour and spectrum. The main sequence of classes runs O, B, A, F, G, K, M from hottest and bluest to coolest and reddest. Our Sun is a yellow G-type star near the middle.
are the example stars correct
Yes. Each spectral class is paired with its true colour, temperature range, and a real example star — Sirius for A, the Sun for G, Betelgeuse for M — so the card you study always matches real astronomy.
why does a star's colour matter
Colour reveals temperature: blue stars are the hottest and red stars the coolest. From colour, astronomers infer temperature, and combined with brightness they can deduce a star's size, age, and stage of life.