3I/ATLAS Methanol-rich Interstellar Comet

Oktay74tn

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3I/ATLAS Methanol-rich Interstellar Comet
Oktay Yürük aka Oktay74tn, science and tech content
https://imgur.com/user/Oktay74tn

This is an artist's image of the interstellar comet 3I/ATLAS illuminated by the Sun. It shows the comet's bright nucleus. The methanol (CH3OH) gas on the side facing the Sun is shown in blue. On the side facing away from the Sun, the hydrogen cyanide HCN gas can be seen in orange. There are several new articles about the composition of the comet.

These are ALMA (Atacama Large Millimeter Array) spectra of 3I/ATLAS and best fit models for semiheavy water HDO, water and methanol in two bands at the nucleus position in grey. The best-fit models are shown in red. The comet has an unusual high methanol to hydrogen cyanide ratio of 70 to 120. 3I/ATLAS was formed under different conditions than the comets of the solar system.

This plot is a comparison of the comet's deuterium (hydrogen-2) to hydrogen-1 isotope ratio with that of the other objects. The two red stars show the lower limits from two datasets. 3I/ATLAS has a minimum D/H ratio of 6.6 thousandths. That is more than thirty times the ratio of the comets in the solar system. The interstellar comet was formed and processed under cold and less irradiated conditions.

3I/ATLAS, in this diagram in red, has a high nitrogen 14 to 15 isotope ratio of 343. This is a comparison to protoplanetary discs (PPDs), pre-stellar cores and protostars, and other comets. The origin of the interstellar comet could be the outer disc of an older low-metallicity star.

This animation shows the path of 3I/ATLAS in the solar system in cyan color. The comet passed the closest point to the Sun, called perihelion, at 1.36 AU in October 2025 (Astronomical Unit, 1 AU is the Earth-Sun distance of 150 million kilometers or 93 million miles). Its maximum velocity was 68 kilometers (42 miles) per second.

This image of the comet was taken with the LSST Camera of the Vera C. Rubin Observatory. After 1I/'Oumuamua and 2I/Borisov, 3I/ATLAS is the third interstellar object ever discovered.

A Direct View of the Chemical Properties of Water from Another Planetary System: Water D/H in 3I/ATLAS
Luis E. Salazar Manzano, Teresa Paneque-Carreno, Martin A. Cordiner, et al.
https://arxiv.org/abs/2603.07026

High nitrogen and carbon isotopic ratios in the interstellar comet 3I/ATLAS
C. Opitom, J. Manfroid, D. Hutsemekers, E. Jehin, et al.
https://arxiv.org/abs/2603.07187

CH3OH and HCN in Interstellar Comet 3I/ATLAS Mapped with the ALMA Atacama Compact Array: Distinct Outgassing Behaviors and a Remarkably High CH3OH/HCN Production Rate Ratio
Nathan X. Roth, Martin A. Cordiner, Dominique Bockelée-Morvan, et al.
https://iopscience.iop.org/article/10.3847/2041-8213/ae433b

Comet 3I/ATLAS
https://science.nasa.gov/solar-system/comets/3i-atlas/

Comet 3I/ATLAS – frequently asked questions
https://www.esa.int/Science_Exploration/Space_Science/Comet_3I_ATLAS_frequently_asked_questions

ALMA Detects Extremely Abundant Alcohol in Interstellar Comet 3I/ATLAS
https://www.almaobservatory.org/en/audiences/alma-detects-extremely-abundant-alcohol-in-interstellar-comet-3i-atlas/

3I/ATLAS is Unusually Rich in Methanol, ALMA Observations Show
https://www.sci.news/astronomy/alma-3i-atlas-methanol-hydrogen-cyanide-14610.html

Wikipedia articles
https://en.wikipedia.org/wiki/3I/ATLAS
https://en.wikipedia.org/wiki/Interstellar_comet
https://en.wikipedia.org/wiki/Vera_C._Rubin_Observatory
https://en.wikipedia.org/wiki/Atacama_Large_Millimeter_Array

Small Objects in the Solar System
DART Impact on Asteroid Dimorphos
https://imgur.com/gallery/dart-impact-on-asteroid-dimorphos-AIVxZoZ

Comet C/2026 A1 MAPS Discovered
https://imgur.com/gallery/comet-c-2026-a1-maps-discovered-d4v7BUA

C/2014 UN271 Largest Comet With Molecular Activity
https://imgur.com/gallery/c-2014-un271-largest-comet-with-molecular-activity-kkTlKZE

Mars Moon Deimos Captured by Hera
https://imgur.com/gallery/mars-moon-deimos-captured-by-hera-pyEcZyX

Asteroid Bennu Contains Tryptophan and Ribose
https://imgur.com/gallery/asteroid-bennu-contains-tryptophan-ribose-7Paynpj

2025 SC79 Near-Earth Asteroid Discovered
https://imgur.com/gallery/2025-sc79-near-earth-asteroid-discovered-Eixzh9R

Venus Co-orbital Asteroids Potential Threat
https://imgur.com/gallery/venus-co-orbital-asteroids-potential-threat-VTcAd2m

3I/ATLAS Brightening Interstellar Comet
https://imgur.com/gallery/3-i-atlas-brightening-interstellar-comet-Lu8Oina

3I/ATLAS New Interstellar Object Discovered
https://imgur.com/gallery/3i-atlas-new-interstellar-object-discovered-aBXeiRl

Asteroid 52246 Donaldjohanson Visited by Lucy Spacecraft
https://imgur.com/gallery/asteroid-52246-donaldjohanson-visited-by-lucy-spacecraft-7KH0SGZ

Vera C. Rubin Observatory's Asteroid Discoveries
https://imgur.com/gallery/vera-c-rubin-observatorys-asteroid-discoveries-V5pX3Zv

Check out https://imgur.com/user/Oktay74tn for many more astronomy and technology videos.

osser

I like these posts.

4 weeks ago |

theyallwenttoMexico

😊👍

MapleSyrupMafia

Not that long ago, I'd see a bunch of recommended vids on YT about how it couldn't be natural. Wonder where those folks are today?

ItHappenedInThe20thCentury

3rd interstellar object *so far*. Let's see how long it takes us to see just loads of them happily passing through our solar system and we just didn't know how to look for them. Super cool. :)

kaijuuGold

i read it as menthol

TK421isAFK

It's moving so fast, it's smokin' through the solar system.

trinxter

Can we put Trump on the next interstellar passer-by?

Put him in another Tesla and chuck it into orbit.

PutItInNeutral

I would settle for throwing him out an airlock in low Earth orbit.

foreverinchains

It would be a whole lot easier to just launch him out of the solar system.

Build a nice little shelter stocked with a decades' worth of food, make sure there are no weapons or sharp, hard edges anywhere inside, drop him in, and send him on his way.

chrispisme

Thank you! I really do appreciate your postings, educational informative and entertaining. Kind of like very short “how the universe works” bits

You are welcome :) .

3I/ATLAS was already moving faster than solar escape velocity when it entered the solar system, and it's very, very fast, but even its fastest speed pales in comparison to Kreutz family sungrazing comets.

https://en.wikipedia.org/wiki/Kreutz_sungrazer

These comets have highly elliptical orbits; from over 15 billion kilometers from the sun at aphelion to under 30,000 kilometers from the surface of the sun at perihelion, and they can reach speeds of over 500 km/s.

Thank you for the information. I have a video about the Comet C/2026 A1 maps which belongs to the Kreutz sungrazers /gallery/comet-c-2026-a1-maps-discovered-d4v7BUA .

mikeatike

I only learned about these when I played High Frontier 4 All.
https://boardgamegeek.com/boardgame/281655/high-frontier-4-all

And don't let the name confuse you. The "4 All" most certainly does not mean it is for everyone. It means "version 4, all modules". Its far and away the most complicated board game I have ever seen. And I've only played the simple versions of it so far.

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