Limits RegistryPUBLIC RECORD
Limits RegistryApollo 10 astronauts Thomas Stafford, John Young, and Gene Cernan reached 39,897 km/h (24,791 mph) relative to Earth on May 26, 1969, during their high-speed return trajectory from the Moon — the fastest any humans have ever traveled. No later crewed mission, including the Moon-landing flights that followed it, has matched or exceeded it.
The question, scope, and sources behind this Registry record.
Apollo 10 astronauts Thomas Stafford, John Young, and Gene Cernan reached 39,897 km/h (24,791 mph) relative to Earth on May 26, 1969, during their high-speed return trajectory from the Moon — the fastest any humans have ever traveled. No later crewed mission, including the Moon-landing flights that followed it, has matched or exceeded it.
The highest speed relative to Earth ever attained by a crewed vehicle.
Change a parameter to stress-test whether a proposed result is still inside the published specification. This is an audit aid, not a proof checker.
This record has no editable parameters. Read the formal question and assumptions before challenging it.
Current frontiers derived from accepted Claims.
An observed or demonstrated result; no opposing bound is implied.
The frontier is not sacred
Most progress starts with a disagreement that survives contact with evidence. If you can push the known lower bound up or pull the upper bound down, show us the work.
≥ when you have shown that at least this value is achievable.≤ when you have shown that anything above this value is impossible.No vibes. State the value, define the scope, and link the paper, proof, code, or reproduction that lets another person check it. Editors review every challenge before the public record changes.
Challenge this recordAssertions tied to evidence, attribution, and review.
The frontier as it changed over time.
Only accepted Claims matching the current specification contribute to the displayed bounds. Strict inequalities remain open; contradictory Claims require editorial review.
1 accepted Claim, with 1 linked evidence records.
Permanent ID limitsregistry.com/limits/LR-APOLLO-10-REENTRY-SPEED
No active verified bounties are linked to this Limit.
View verified bounty tracker ↗No accepted machine-checked reproductions are recorded for this Limit.
Limits Registry. LR-APOLLO-10-REENTRY-SPEED. Fastest speed ever traveled by humans. 2026.