Record #00428Space archive
Most Massive Known Black Hole
TON 618 is an ultramassive black hole associated with a luminous quasar, often estimated at about 66 billion solar masses. Its ranking and mass remain dependent on indirect estimation methods.
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Overview
Archive NoteTON 618's mass is inferred indirectly from quasar emission-line properties and assumptions about the broad-line region rather than direct dynamical weighing.
Published calibrations differ. A 2024 study discusses an estimate near 40.7 billion solar masses, so the commonly quoted 66-billion figure should not be treated as exact.
Record history
1 Milestones- about 66 billion solar massesTON 618Current Record
Sources
Evidence & ReferencesVerification basis and limitations
Evidence-backedCredible sources support core facts; the comparison scope or corroboration remains incomplete.
Basis: corroborating reliable secondary materials
NASA cites an estimate of roughly 66 billion solar masses for TON 618; another academic study discusses a model estimate near 40.7 billion. The mass is inferred from quasar emission-line methods, not direct dynamical weighing, and its ranking depends on adopted estimates.
Comparison boundaries still under review
Mass is model-dependent; published estimates discussed here range from roughly 40.7 to 66 billion solar masses, and the ranking may change.
- Verification assessment
- 2026-11-07
- Last editorial review
- 2026-11-07
Current Entry identifies the current entry in this archive; it does not establish that the record is still held today.
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