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Interstellar Comet 3I/ATLAS Reveals Surprising Composition Data

3/23/2026

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Summary

Story summary

Interstellar comet 3I/ATLAS is the third known object from outside our solar system, discovered in July 2025.
The comet travels at over 210,000 km/h.
It sheds water and organic molecules, with water loss at about 40 kg per second.
NASA and ESA missions, including the Juice spacecraft, have gathered data on its composition.
The data show a carbon dioxide to water ratio of 8:1, challenging existing models of planetary formation.

History

Historical Context

Comet Hale-Bopp was discovered on July 22, 1995, by amateur astronomers Thomas Bopp and Alan Hale, marking a pivotal moment in astronomy. With a nucleus estimated at 40 kilometers wide, it became one of the largest comets observed. The recent discovery of interstellar comet 3I/ATLAS further challenges our understanding of planetary formation, highlighting the significance of these celestial bodies in studying the solar system's origins.

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Story summary

Interstellar comet 3I/ATLAS is the third known object from outside our solar system, discovered in July 2025.
The comet travels at over 210,000 km/h.
It sheds water and organic molecules, with water loss at about 40 kg per second.
NASA and ESA missions, including the Juice spacecraft, have gathered data on its composition.
The data show a carbon dioxide to water ratio of 8:1, challenging existing models of planetary formation.

1 / 2