Tootfinder

When checking the brightness development of the fascinating #Kreutz #comet #MAPS with https://cobs.si one sees that the observations so far all nicely sit on a standard comet curve with a high n of ~6.7 i.e. the nucleus responds vividly but also calmly to the increasing solar heat. While the extrapolation with three different models is quite something, with peak magnitudes - directly next to the Sun in the sky, of course - of either -5 mag., -20 mag. or -40 mag. Scary stuff ... ;-) But seriously, some special math for sungrazer brightness trends will kick in at some point before perihelion is reached.

And here is now also a spectrum of #comet #3I/ATLAS taken during the #ShadowTheScientists session on 26 November, from https://www.astronomerstelegram.org/?read=17561 - CN (388 nm), C3 (402 nm) and C2 (474 nm/517 nm) are detected. Meanwhile the paper https://arxiv.org/abs/2512.18341 concludes from the non-gravitational acceleration that the diameter of the comet's nucleus is 820 to1050 m.

The JWST has looked at #comet C/2025 K1 (ATLAS) again, in four filters yesterday and today: from the raw images - https://yuval-harpaz.github.io/astro/jwst_latest_release.html - comes this false color image, https://www.flickr.com/photos/197464132@N05/55012773369/

The Ongoing Decline in Activity of #Comet 103P/Hartley 2: #CitizenScience #Unistellar

🇺🇦 #NowPlaying on #BBC6Music's #RileyAndCoe
Comet Gain:
🎵 Seven Sisters To Silverlake
#CometGain
https://comet-gain.bandcamp.com/track/from-seven-sisters-to-silverlake
https://open.spotify.com/track/09hOsne5O1atEiTWNioBhk

High resolution Near IR images of fragmenting #comet C/2025 K1 (ATLAS) on 19 December from the JWST: on the left one of two raw images which just appeared on https://yuval-harpaz.github.io/astro/jwst_latest_release.html, on the right two false-color images from both images published in https://www.reddit.com/r/jameswebb/comments/1prolrq/fragmented_comet_c2025_k1_atlas_nircam/ and
https://bsky.app/profile/cheribliss.bsky.social/post/3mahu4to7ss2f (and further processed by me).

There is also a #PUNCH video showing only #comet #Lemmon and its tails in https://science.nasa.gov/blogs/punch/2025/12/19/nasas-punch-spies-comet-lemmon/ - unfortunately too faint so much tail structure gets lost which can be glimpsed in the full video. But the data are there, waiting for someone to process them for science.

For optics large enough there is an amazing #comet in the - southern - sky right now, C/2024 E1 (Wierzchos): an image taken by Gerald Rhemann and Michael Jäger remotely in Namibia, https://www.facebook.com/photo/?fbid=25304451112588622
Date: 26 01 2026 UT 18:47
Location: Farm Tivoli, Namibia
Telescope: ASA Astrograph 12" f3.6
Camera: ZWO ASI 6200 MM Pro
Mount: ASA DDM 85
Exp.Time: LRGB 7.8/5/5/5 min.

First the nucleus of #comet SWAN split - https://skyweek.wordpress.com/2025/11/02/allgemeines-live-blog-ab-dem-2-november-2025/#Nov06 ("Der Kern des Kometen C/2025 R2 (SWAN) ist zerbrochen ...") - and now C/2025 K1 (ATLAS) has suffered the same fate: a 2-meter-telescope image from https://www.astronomerstelegram.org/?read=17487 ("Multiple Fragmentation Observed"), also https://groups.io/g/comets-ml/topic/116216567 (several amateur observations) and https://www.astronomerstelegram.org/?read=17488 (Hubble detections of more fragments, sadly no pictures included).

And here comes my #Bochum, Germany, #Lemmon number 6: today it was very clear for a change, and the #comet with quite some tail (an effect of the imminent perigee?) showed up nicely - and even faintly in binoculars - at the end of nautical twilight.

The new #Kreutz #comet discovered unusually early has been named C/2026 A1 (MAPS): #photosphere on 4 April and becoming a bright comet.

The new #Kreutz #comet is now C/2026 A1 (MAPS): http://www.cbat.eps.harvard.edu/iau/cbet/005600/CBET005658.txt and #perihelion is highly uncertain but there is hope as https://www.facebook.com/groups/227002358661288/posts/1670699484291561 and https://groups.io/g/comets-ml/topic/117373975#msg34667 explain. And if MAPS makes it to perihelion and is (very) bright then coronagraphs on the ground might be able to catch it against the inner corona as the following table - calculated with https://ssd.jpl.nasa.gov/horizons/app.html#/ - shows.