NASA's New Horizons flew past the Kuiper Belt object Arrokoth (2014 MU69) on 1 January 2019 at a distance of about 3,500 km, when Arrokoth was about 6.6 billion km from the Sun. Arrokoth turned out to be a pristine contact binary, offering clues to how planetesimals formed.
The question, scope, and sources behind this Registry record.
NASA's New Horizons flew past the Kuiper Belt object Arrokoth (2014 MU69) on 1 January 2019 at a distance of about 3,500 km, when Arrokoth was about 6.6 billion km from the Sun. Arrokoth turned out to be a pristine contact binary, offering clues to how planetesimals formed.
The greatest heliocentric distance of any celestial body visited at close range by a spacecraft.
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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.
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The frontier as it changed over time.
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Permanent ID limitsregistry.com/limits/LR-FARTHEST-OBJECT-EXPLORED
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Limits Registry. LR-FARTHEST-OBJECT-EXPLORED. Farthest object ever explored by a spacecraft. 2026.