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Interstellar Comet 3I/ATLAS Reveals Secrets Before Sun Encounter

12/17/2025

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Summary

Story summary

Interstellar comet 3I/ATLAS shows non-gravitational acceleration due to outgassing as it approaches the Sun.
Some misconceptions claim it is a disguised spacecraft.
Researchers measured its acceleration at about half a micron per second squared.
A study estimates the nucleus mass at 44 million metric tons and about 375 meters long.
The findings were published in Research Notes of the American Astronomical Society.

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Story summary

Interstellar comet 3I/ATLAS shows non-gravitational acceleration due to outgassing as it approaches the Sun.
Some misconceptions claim it is a disguised spacecraft.
Researchers measured its acceleration at about half a micron per second squared.
A study estimates the nucleus mass at 44 million metric tons and about 375 meters long.
The findings were published in Research Notes of the American Astronomical Society.