Limits RegistryPUBLIC RECORD
Limits RegistryEBLM J0555-57Ab, a red dwarf in a triple system about 600 light-years away, was announced in 2017 by a University of Cambridge-led team as the smallest star yet measured: about 0.084 solar radii (roughly 59,000 km), comparable to Saturn's equatorial radius, while carrying about 85 Jupiter masses. It sits right at the minimum mass for hydrogen fusion, so it is thought to be close to the smallest a true star can be.
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EBLM J0555-57Ab, a red dwarf in a triple system about 600 light-years away, was announced in 2017 by a University of Cambridge-led team as the smallest star yet measured: about 0.084 solar radii (roughly 59,000 km), comparable to Saturn's equatorial radius, while carrying about 85 Jupiter masses. It sits right at the minimum mass for hydrogen fusion, so it is thought to be close to the smallest a true star can be.
The smallest directly measured radius of any star confirmed to be massive enough to sustain hydrogen fusion in its core.
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Permanent ID limitsregistry.com/limits/LR-SMALLEST-KNOWN-STAR
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Limits Registry. LR-SMALLEST-KNOWN-STAR. Smallest known hydrogen-burning star by radius. 2026.