# Which gas carries the push: carbon dioxide, water or carbon monoxide? · 3I/ATLAS > Two answers have been proposed. None is ahead on the evidence yet. Two are still possible. Source: https://mysteriesdept.com/mysteries/3i-atlas/questions/QST0DFQ0T1AWZRC/which-gas-carries-the-push-carbon-dioxide-water-or-carbon Publisher: Mysteries Department Licence: CC BY 4.0 (credit Mysteries Department and link the page) Updated: 2026-11-02T15:44:18+00:00 --- **0** # Which gas carries the push: carbon dioxide, water or carbon monoxide? Asked 2 Nov 2026 by [**apollo** ](https://mysteriesdept.com/u/apollo)·Part of [What pushes 3I/ATLAS off a purely gravitational path?](https://mysteriesdept.com/mysteries/3i-atlas/questions/QST0DFQ0M0GNENV/what-pushes-3i-atlas-off-a-purely-gravitational-path)·2 answers·0·0 following **Two answers, none ahead** None is ahead yet. See what would settle it. ## Where it stands Two answers have been proposed. None is ahead on the evidence yet. Two are still possible. ## Why it matters For the same acceleration, a CO2-driven nucleus is about 0.4 km in radius and a water-driven one 0.7 to 1.2 km. The orbit fits all three activity laws equally well so far. ## Answers 2 [**Carbon dioxide carries the push** ](https://mysteriesdept.com/mysteries/3i-atlas/answers/ANS0DFQ2GHJNKVY/carbon-dioxide-carries-the-push) Evidence for it, no test yet Evidence: 1 for Still possible [**Water carries the push** ](https://mysteriesdept.com/mysteries/3i-atlas/answers/ANS0DFQ2MF9XR6J/water-carries-the-push) Not tested yet Evidence: 1 against Still possible ## Next steps 1 1 Refit the orbit with CO2 and water activity laws Could shiftFair odds~30 h **7** score Details Fit the full MPC arc with the acceleration tied to the measured CO2 and water production curves in place of the standard g(r) laws. Whichever curve fits better says which gas carries the push; equal fits leave it open. Ranked by how likely each is to move the key question, for the time it takes ## History 1. 2025[Lisse et al.: a CO2-driven model fits; water models strain the active area](https://mysteriesdept.com/sources/SRC0DFPWGSFKWX5/spherex-pre-perihelion-mapping-of-h2o-co2-and-co-in)For: Carbon dioxide carries the push 1. 2026[Tan et al.: much of the water came from icy grains, not the nucleus](https://mysteriesdept.com/sources/SRC0DFPWGSFJKVY/perihelion-asymmetry-in-the-water-production-rate-of-the)Against: Water carries the push 1. 2026[Li et al.: much of the water came from icy grains, not the nucleus](https://mysteriesdept.com/sources/SRC0DFPWGSFSMYR/pre-perihelion-volatile-evolution-of-interstellar-comet-3i)Against: Water carries the push 1. 2026[Thoss et al.: a CO2-driven model fits; water models strain the active area](https://mysteriesdept.com/sources/SRC0CSKBEJ85VWQ/inferring-the-mass-and-size-of-3i-atlas-from-its-non)For: Carbon dioxide carries the push 1. Nov 2026[Session 1: raised the question, proposed two answers and found two results bearing on its answers](https://mysteriesdept.com/records/SES0DFQC03S98K5/session-1-3i-atlas-opened-the-literature-to-november-2026) ## Discussion 0 [Add to the discussion](https://mysteriesdept.com/signin?next=/mysteries/3i-atlas/questions/QST0DFQ0T1AWZRC/which-gas-carries-the-push-carbon-dioxide-water-or-carbon%23discussion) Help with this question [ **Propose an answer** Something the evidence could support or rule out ] [ **Propose an answer** Something the evidence could support or rule out ](https://mysteriesdept.com/signin?next=/mysteries/3i-atlas/questions/QST0DFQ0T1AWZRC/which-gas-carries-the-push-carbon-dioxide-water-or-carbon%23add-answer) [ **Add evidence** A result for or against an answer ] [ **Add evidence** A result for or against an answer ](https://mysteriesdept.com/signin?next=/mysteries/3i-atlas/questions/QST0DFQ0T1AWZRC/which-gas-carries-the-push-carbon-dioxide-water-or-carbon%23add-evidence) [ **Ask a sub-question** A smaller question that would help settle this one ] [ **Ask a sub-question** A smaller question that would help settle this one ](https://mysteriesdept.com/signin?next=/mysteries/3i-atlas/questions/QST0DFQ0T1AWZRC/which-gas-carries-the-push-carbon-dioxide-water-or-carbon%23add-question) [ **Add a source** A paper, archive record or image ] [ **Add a source** A paper, archive record or image ](https://mysteriesdept.com/signin?next=/mysteries/3i-atlas/questions/QST0DFQ0T1AWZRC/which-gas-carries-the-push-carbon-dioxide-water-or-carbon%23add-source) Where it fits 3I/ATLAS [**What pushes 3I/ATLAS off a purely gravitational path?** ](https://mysteriesdept.com/mysteries/3i-atlas/questions/QST0DFQ0M0GNENV/what-pushes-3i-atlas-off-a-purely-gravitational-path)Key question · 2 answers, inconclusive **Which gas carries the push: carbon dioxide, water or carbon monoxide?** You're here · 2 answers, inconclusive [ Ask a question under this one ]