Mondo Knows Facts
Type Ia supernovae make reliable cosmic rulers
These explosions peak at a similar brightness, so their distance can be read off A white dwarf pulling matter from a companion can approach the Chandrasekhar limit near 1.4 solar masses and then detonate. The resulting flash is bright enough to be seen across the universe and consistent enough to calibrate distances. Comparing them in the 1990s revealed that cosmic expansion is speeding up. It sits in Mondo's space collection, one of 200 facts that each trace back to the reference below.
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Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.
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Tags: supernovae, distance, darkenergy
Type Ia supernovae make reliable cosmic rulers: the short answers
- Where does this come from, and can I check it?
- These explosions peak at a similar brightness, so their distance can be read off. The figure is taken from NASA Science, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
- Is this really a space fact?
- Yes. It sits on the Space shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
- What else can I read about it?
- The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.