Kuuke's SterrenbeeldenMar 10
3I/ATLAS is ongewoon rijk aan methanol
Astronomen hebben met behulp van ALMA waterstofcyanide en ongewoon hoge concentraties methanol gedetecteerd in de interstellaire komeet 3I/ATLAS. Waterstofcyanide (HCN/blauwzuur)
#3I/ATLAS #alma #blauwzuur #InterstellaireKomeet #komeet #methanol #waterstofcyanide #zonnestelsel
https://www.kuuke.nl/3i-atlas-is-ongewoon-rijk-aan-methanol/
Kuuke's SterrenbeeldenMar 1
Juice ziet de interstellaire komeet 3I/ATLAS
De JANUS wetenschappelijke camera aan boord van de JUICE ruimtesonde van de ESA heeft nieuwe beelden vastgelegd van de interstellaire
#3I/ATLAS #InterstellaireKomeet #janus #juice #komeet #zonnestelsel
https://www.kuuke.nl/juice-ziet-de-interstellaire-komeet-3i-atlas/
Umberto gaetaniFeb 27

Juice ha fotografato 3I/Atlas al perielio

#3I/Atlas @astronomia

Impossibile da osservare dalla Terra, il passaggio vicino al Sole della cometa interstellare 3I/Atlas è stato immortalato dallo spazio dalla fotocamera Janus della missione Juice dell’Esa. Si tratta di immagini uniche, che mostrano una chioma estesa e una coda con numerose strutture.

https://umbertogaetani.substack.com/p/juice-ha-fotografato-3iatlas-al-perielio

Michael BuschFeb 25

The International Astronomical Union's outreach office has published a good overview of the case of #3I/ATLAS:

https://iauoutreach.org/comet-3I/ATLAS

Explicitly to counter the blatant nonsense that has been promoted about it, by providing the facts instead.

3I/ATLAS

3I/ATLAS is an interstellar object a small body that does not belong to our Solar System and is passing through it from elsewhere in the Milky Way. It is only the third confirmed interstellar object ever observed. In terms of appearance and behaviour, 3I/ATLAS looks and behaves like a typical comet from the outer Solar System.

Umberto gaetaniFeb 16

L'Osservatorio Rubin NSF-DOE ha individuato la cometa 3I/ATLAS dieci giorni prima della sua scoperta

#3I/ATLAS @astronomia

3I/ATLAS : La sua prima segnalazione risale al 1° luglio 2025, effettuata dal sistema (ATLAS). Tuttavia, era apparso già dieci giorni prima, il 21 giugno 2025, nei dati ad alta risoluzione acquisiti durante le prove di commissioning con la LSST Camera da 3200 megapixel del Rubin Observatory.

https://umbertogaetani.substack.com/p/losservatorio-rubin-nsf-doe-ha-individuato

Kuuke's SterrenbeeldenFeb 2
Zeldzame kosmische uitlijning geeft Hubble een goed zicht op 3I/ATLAS
Op 22 januari 20216 nam de Hubble Space Telescope de interstellaire komeet 3I/ATLAS was. De komeet was vrijwel perfect uitgelijnd
#3I/ATLAS #aarde #hubble #InterstellaireKomeet #komeet #zon #zonnestelsel
https://www.kuuke.nl/zeldzame-kosmische-uitlijning-geeft-hubble-een-goed-zicht-op-3i-atlas/
EmergentSageFeb 1

There is utility in the rummaging through the discard pile. #3I #ATLAS #MeerKAT #OH #Lband #RadioAstronomy #InterstellarObjects #CometScience

https://doi.org/10.5281/zenodo.18446003

Narrowband Solar Attenuation by 3I/ATLAS: Geometry, Physical Plausibility, and the Case for Deep Residual Analysis

The MeerKAT L‑band observation of 3I/ATLAS on 24 October 2025 provides a rare opportunity to study narrowband solar attenuation during a near‑conjunction geometry. According to ATel 17473 (Pisano et al. 2025), two ground‑state OH absorption lines were detected at a Doppler velocity of approximately −15.6 km s⁻¹, with preliminary full widths at half maximum of 0.88 km s⁻¹ (1665 MHz) and 1.26 km s⁻¹ (1667 MHz). If these values are confirmed in the final calibrated dataset, the difference in line width is larger than expected for purely thermal or isotropic outgassing and may indicate additional structure in the absorbing medium. This paper outlines the physical implications of the geometry, describes what a distant aligned observer might detect, and argues that the apparent “noise” in the published spectra warrants deeper analysis once the dataset becomes publicly available. No claims are made about non‑natural structure; the goal is to articulate why the physics alone justifies a closer look.

Zenodo
Kuuke's SterrenbeeldenJan 31
TESS neemt de interstellaire komeet 3I/ATLAS waar
Tijdens een speciale waarneemronde eerder deze maand registreerde de TESS-ruimtetelescoop de subtiele gloed en staart van de interstellaire komeet. Deze
#3I/ATLAS #InterstellairObject #InterstellaireKomeet #komeet #TESS #zonnestelsel
https://www.kuuke.nl/tess-neemt-de-interstellaire-komeet-3i-atlas-waar/
astronomydomineJan 30

#hubble
#3I/Atlas
Nucleus and Postperihelion Activity of Interstellar Object 3I/ATLAS Observed by Hubble Space
Telescope

https://arxiv.org/pdf/2601.21569

Michael BuschJan 26

Today on the #arXiv:

Hoogendam et al. 2026, "Post-Perihelion Integral Field Spectroscopy of the Interstellar Comet 3I/ATLAS" - https://arxiv.org/abs/2601.16983

#3I/ATLAS continues to be a typical comet apart from where it came from. Including the near-solar amounts of iron and nickel.

Post-Perihelion Integral Field Spectroscopy of the Interstellar Comet 3I/ATLAS

The environs of other stellar systems may be directly probed by analyzing the cometary activity of interstellar objects. The recently discovered interstellar object 3I/ATLAS was the subject of an intensive worldwide follow-up campaign in its pre-perihelion approach. Now, 3I/ATLAS has begun its post-perihelion departure from the Solar System. In this letter, we report the first post-perihelion blue-sensitive integral-field unit spectroscopy of 3I/ATLAS using the Keck Cosmic Web Imager on November 16, 2025. We confirm previously reported CN, Fe, and Ni outgassing along with detections of carbon chain molecules $\mathrm{C}_2$ and $\mathrm{C}_3$. We calculate production rates for each species. We find Fe and Ni production rates of $\mathrm{Q_{Fe}} = (9.55\pm3.96)\times10^{25}$ atoms s$^{-1}$, and $\mathrm{Q_{Ni}} = (6.61\pm2.74)\times10^{25}$ atoms s$^{-1}$, resulting in a ratio of $\log(\mathrm{Q_{Ni}} / \mathrm{Q_{Fe}}) = -0.16\pm0.03$, which matches Solar System comets well and continues the pre-perihelion trend of declining $\log(\mathrm{Q_{Ni}} / \mathrm{Q_{Fe}})$ with $r_h$. We investigate the radial distributions of these elemental species and find characteristic $e$-folding radii of 3880$\pm$39 km for Ni, 6053$\pm$68 km for CN, 4194$\pm$45 km for $\mathrm{C}_2$, and 3833$\pm$45 km for $\mathrm{C}_3$. Compared to pre-perihelion measurements, these radii have increased by a factor of $\sim$6.5--7. Our post-perihelion observations reveal that 3I/ATLAS continues to exhibit cometary behavior broadly consistent with Solar System comets.

arXiv.org