Hi again Thomas,
Thanks for posting this image. I agree it does show an extended
coma.When was this taken and with what instumentation? As you say
heavily processed, would such faint feature be visible to an observer at
a dark sky site. I know that there are obsevers who can see vaery faint
features that others cannot. I remember Brian Marsden commenting that
George Alcock was able to see very faint comet comas and tail
details(real) that were not seen by others.
? Comet observing is so heavily influenced by observing conditons,
whether it be imaging or visually.
Why do you think we are seeing this extensive coma, there has been no
outburst of the central condensation. When 12p had central condensation
outbursts there seemed to be no substantial increase in the total
integrated magnitude. With this comet, are we seeing an increase in the
total integrated magnitude without any outburst of the central
condensation? How are we seeing material being released from the central
condensation into the coma to increase its brightness and overall size
without any sign of increased activity from the central condensation.
With 29p we see outbursts measured using small apertures which then
produce material to populate the coma and make it larger and brighter
and expanding.
Perhaps we can hear from some of the comet scientists in anwering these
questions.
As I said comets eh!
Best wishes
Denis


??????? ------ Original Message ------
??????? From: t.lehmann@...
??????? To: [email protected]
??????? Sent: Saturday, December 28th 2024, 12:05
??????? Subject: Re: [comets-ml] Unusual brightening of comet C/2023 Q1



? Hi Denis,

? here is a heavily processed image. Pretty ugly though, but it might
serve for
? illustration purposes.

? Something I'd add to my "total" coma mesurement within 5': the
brighness
? measurement (statistical) uncertainty is about 0.15mag.

? Best wishes
? Thomas


? > Am Sat, 28 Dec 2024 11:43:28 +0000 (GMT)
? > schrieb "Denis Buczynski via groups.io" :
? >
? > Hi Thomas,
? > I appreciate all you say in this regard.
? > I would be more convinced that there was an extensive coma present
if I
? > could see an image showing this coma. Whether it be from fast f/2
? > telescopes in excellent dark skies or from anywhere else . It only
? > requires someone posting a current image showing an extensive coma
to
? > put this "debate " to rest.We have yet to see one.
? > Best wishes
? > Denis Buczynski
? >
? >
? >???????? ------ Original Message ------
? >???????? From: t.lehmann@...
? >???????? To: jjgsgp@...
? > Cc: [email protected]
? >???????? Sent: Saturday, December 28th 2024, 11:17
? >???????? Subject: Re: [comets-ml] Unusual brightening of comet C/2023
Q1
? >
? >
? >
? >?? Dear all,
? >
? >?? thanks for the numerous observation reports, especially to Denis's
and
? > Peter's
? >?? measurements over longer time span.
? >
? >?? I'd like to emphasize that any brightness measurement MUST be read
in
? >?? conjunction to the measurement aperture used. The aperture
diameter
? > MUST be
? >?? taken into account when comparing data. The second important
parameter
? > is
? >?? the spectral range covered. The brightening from gaseous outbursts
can
? > be
? >?? more prominent in the green filtered images than in unfiltered (or
? > red) images.
? >
? >?? About visual estimates.
? >?? My report of 2024-12-23.46 UT, m1=14.1, coma diam. 5'
? >?? is derived from images using a fast f/2.2 scope under excellent
skies
? > having
? >?? a limited stellar magnitude of 21mag and using heavy smoothing and
? > contrast
? >?? enhancement. I would be very much surprised if it would be
possible to
? > detect
? >?? the same amount of coma size visually. It is even harder for me to
? > accept that
? >?? I have missed 90% of the comets coma flux in my measurement -
which
? > would be
? >?? the case if the magnitude were near ~11.6mag - though I cannot
rule
? > out some
? >?? additional outburst has happened recently.
? >
? >?? Anyway, I'd like to encourage anyone to continue monitoring the
comet.
? >?? For those doing imaging, it would be nice if you could measure the
? > coma
? >?? additionally using a true aperture diameter of d=15000km and
30000km
? > at the
? >?? comet (and report filter information) so we would be able to
construct
? > a
? >?? combined light curve of the inner coma brightness.
? >
? >?? Thanks
? >?? Thomas
? >
? >
? >?? > Am Sat, 28 Dec 2024 07:54:29 +0100
? >?? > schrieb "jjgonzalez jjgonzalez via groups.io"
? > <jjgsgp@...>:
? >?? >
? >?? > Thomas, Denis, Alan, all,
? >?? >
? >?? > Obviously, I am also interested in the confirmation of the large
and
? > very
? >?? > diffuse gas coma by visual observers from dark skies.
? >?? >
? >?? > Best regards,
? >?? >
? >?? > J. J. Gonzalez Suarez
? >?? >
? >?? > P.S.:
? >?? >
? >?? > As complementary information, this is the report of my recent
? > observation
? >?? > of the large dust coma of 29P :
? >?? >
? >?? > 29P/Schwassmann-Wachmann:
? >?? > 2024 Dec. 27.00 UT: m1=11.1, Dia.=4', DC=2/, 20 cm SCT (77x).
? >?? > ( Cubiellos - Sierra del Aramo, 1510 m, Asturias, Spain )
? >?? >
? >?? >
? >
-----------------------------------------------------------------------------------------------------------
? >?? >
? >?? >
? >?? > On Sat, Dec 28, 2024 at 5:39?AM Alan Hale via groups.io
? > [email protected]> wrote:
? >?? >
? >?? > > Dear Denis, all,
? >?? > >
? >?? > >
? >?? > >
? >?? > > I’m attaching an image I took of C/2023 Q1 via LCO-Tenerife on
? > December
? >?? > > 26.97 UT (0.35-m Cassegrain, single 180-second image,
unprocessed,
? >?? > > uncropped (dimensions 30x30 arcmin)). I’ve had some trouble
? > getting
? >?? > > measurements from the image (possible software issues), but
would
? >?? > > “guesstimate” the magnitude to be somewhere around 15-15.5. I
had
? > not
? >?? > > imaged the comet previously so I can’t comment about any
recent
? > brightening.
? >?? > >
? >?? > >
? >?? > >
? >?? > > For comparison, I’m also attaching an image I took of 29P on
? > December
? >?? > > 25.60 UT from LCO-Haleakala (0.35-m Cassegrain, single
150-second
? > image,
? >?? > > also unprocessed and uncropped, 30x30 arcmin). About eight
hours
? > before I
? >?? > > took this image I observed the comet visually at m1 = 11.7,
5.5’
? > coma, DC
? >?? > > ~1 (41 cm reflector, 70x).
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > > Sincerely,
? >?? > >
? >?? > > Alan
? >?? > >
? >?? > >
? >?? > >
? >?? > > Hello all,
? >?? > >
? >?? > > I must admit I am a little baffled by these reports of a
? > substantial
? >?? > >
? >?? > > increase in brightness of C/2023 Q1.
? >?? > >
? >?? > > Firstly Thomas? Lehmann reported an increase in the brightness
of
? > this
? >?? > >
? >?? > > comet in November to mag 14.1 My observations made for
astrometry
? > for
? >?? > >
? >?? > > the months of November and December (10 nights data) show the
? > comet only
? >?? > >
? >?? > > increasing from mag 17 to mag 16.
? >?? > >
? >?? > > This is borne out by Peter Carson and Francois Kugel's
comments of
? > their
? >?? > >
? >?? > > own observations and measurements.
? >?? > >
? >?? > > Now JJ Gonzalez is reporting an observation on the night of
Dec 27
? > of
? >?? > >
? >?? > > this comet with a magnitude of 11.6.
? >?? > >
? >?? > > My last observation was a day or so earlier on Dec 25 and my
? > Comphot
? >?? > >
? >?? > > measurement gives a magnitude of 15.73 with a coma diameter of
34
? > arc
? >?? > >
? >?? > > secs.
? >?? > >
? >?? > > I attach my image.
? >?? > >
? >?? > >?? Can someone confirm the apparent +4 mag increase in
brightness
? > or of
? >?? > >
? >?? > > mine, Peter Carson's and Francois Kugel's observation results?
? >?? > >
? >?? > >
? >?? > >
? >?? > > Comets eh!
? >?? > >
? >?? > >?? Happy NY
? >?? > >
? >?? > > Denis Buczynski
? >?? > >
? >?? > > BAA Comet Section
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >???????? ------ Original Message ------
? >?? > >
? >?? > >???????? From: jjgsgp@...
? >?? > >
? >?? > >???????? To: [email protected]
? >?? > >
? >?? > >???????? Sent: Friday, December 27th 2024, 23:52
? >?? > >
? >?? > >???????? Subject: Re: [comets-ml] Unusual brightening of comet
? > C/2023 Q1
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >?? Thomas, all,After reading your email sent to the list
yesterday,
? > I
? >?? > >
? >?? > > have arranged an observing session for tonight. This is the
report
? >?? > >
? >?? > > :C/2023 Q1 (PANSTARRS):2024 Dec. 27.81 UT: m1=11.6, Dia.=6',
? > DC=1/, 20
? >?? > >
? >?? > > cm SCT (77x).[ From dark mountain skies the comet appears
visually
? > much
? >?? > >
? >?? > > brighter than expected, showing a faint, large and very
diffuse
? > outer
? >?? > >
? >?? > > coma. Nearby field stars checked in DSS. Limiting star
magnitude
? > near
? >?? > >
? >?? > > comet : 14.2 (AQ).].( Cubiellos - Sierra del Aramo, 1510 m,
? > Asturias,
? >?? > >
? >?? > > Spain ). All the best from the Cantabrian Mountains,J. J.
Gonzalez
? >?? > >
? >?? > >
? >?? > >
? >
Suarez--------------------------------------------------------------------------------------------------------------------------
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >?? On Fri, Dec 27, 2024 at 5:28?PM Shanklin, Jonathan D. via
? > groups.io
? >?? > >
? >?? > > <jdsh@...> wrote:
? >?? > >
? >?? > >?????????? My entry for the comet for The Astronomer magazine
? > covering
? >?? > >
? >?? > > observations to the end of November and giving the behaviour
for
? >?? > >
? >?? > > November was:
? >?? > >
? >?? > >??? 2023 Q1 (PANSTARRS) observations cover: -144 to -16 days,
2.6 –
? > 3.0
? >?? > >
? >?? > > au
? >?? > >
? >?? > >??? At 17.5, steady (Carson, Pappa)
? >?? > >
? >?? > >
? >?? > >
? >?? > >??? Which does suggest that the brightness seen in December is
? >?? > >
? >?? > > unexpected.
? >?? > >
? >?? > >
? >?? > >
? >?? > >??? I won’t start putting the TA column for the next issue
together
? > until
? >?? > >
? >?? > > around January 4.
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >??? Regards,
? >?? > >
? >?? > >
? >?? > >
? >?? > >??? Jonathan Shanklin
? >?? > >
? >?? > >??? BAA Comet Section visual observations co-ordinator
? >?? > >
? >?? > >???
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >????? From: [email protected] <[email protected]> On Behalf
Of
? > Peter
? >?? > >
? >?? > > Carson via groups.io Sent: Friday, December 27, 2024 3:37 PM
To:
? >?? > >
? >?? > > [email protected] Subject: [comets-ml] Unusual brightening
of
? > comet
? >?? > >
? >?? > > C/2023 Q1
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >??????? You don't often get email from
? >?? > >
? >?? > > petercarson100@.... Learn why this is
important
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >???? Hello Thomas,
? >?? > >
? >?? > >
? >?? > >
? >?? > >???? Here are my observations from summer to now.
Unfortunately, I
? > made
? >?? > >
? >?? > > no observations in October and early November, so although the
? > comet has
? >?? > >
? >?? > > brightened, it is not? clear if the brightening occurred over
a
? > short or
? >?? > >
? >?? > > long period.
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >???? All the best
? >?? > >
? >?? > >
? >?? > >
? >?? > >???? Peter
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >???? Type Comet Obs???????????????????????? date Meth
? >?? > >
? >?? > > Mag Refcat Inst T App Inst F Inst P Coma User Location
? >?? > >
? >?? > >
? >?? > >
? >?? > >???? CCD C/2023 Q1 22/12/2024
? >?? > >
? >?? > > 21:11 Z 15.6 GG C 31.5 8 1260 0.80' CAR06 PGC
? >?? > >
? >?? > > Observatory Z10, Fregenal de la sierra, Spain
? >?? > >
? >?? > >
? >?? > >
? >?? > >???? CCD C/2023 Q1 10/12/2024
? >?? > >
? >?? > > 03:18 Z 15.9 GG C 31.5 8 1200 0.80' CAR06 PGC
? >?? > >
? >?? > > Observatory Z10, Fregenal de la sierra, Spain
? >?? > >
? >?? > >
? >?? > >
? >?? > >???? CCD C/2023 Q1 27/11/2024
? >?? > >
? >?? > > 02:43 Z 16.1 GG C 31.5 8 1200 0.80' CAR06 PGC
? >?? > >
? >?? > > Observatory Z10, Fregenal de la sierra, Spain
? >?? > >
? >?? > >
? >?? > >
? >?? > >???? CCD C/2023 Q1 04/09/2024
? >?? > >
? >?? > > 01:48 Z 17.5 GG C 31.5 8 1200 0.40' CAR06 PGC
? >?? > >
? >?? > > Observatory Z10, Fregenal de la sierra, Spain
? >?? > >
? >?? > >
? >?? > >
? >?? > >???? CCD C/2023 Q1 16/08/2024
? >?? > >
? >?? > > 03:21 Z 17.1 GG C 31.5 8 960 0.40' CAR06 PGC
? >?? > >
? >?? > > Observatory Z10, Fregenal de la sierra, Spain
? >?? > >
? >?? > >
? >?? > >
? >?? > >???? CCD C/2023 Q1 05/08/2024
? >?? > >
? >?? > > 02:33 Z 17.4 GG C 31.5 8 960 0.40' CAR06 PGC
? >?? > >
? >?? > > Observatory Z10, Fregenal de la sierra, Spain
? >?? > >
? >?? > >
? >?? > >
? >?? > >???? CCD C/2023 Q1 16/07/2024
? >?? > >
? >?? > > 02:52 Z 17.5 GG C 31.5 8 1080 0.40' CAR06 PGC
? >?? > >
? >?? > > Observatory Z10, Fregenal de la sierra, Spain
? >?? > >
? >?? > >
? >?? > >
? >?? > >???? CCD C/2023 Q1 10/07/2024
? >?? > >
? >?? > > 02:39 Z 17.5 GG C 31.5 8 1200 0.40' CAR06 PGC
? >?? > >
? >?? > > Observatory Z10, Fregenal de la sierra, Spain
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >???? From: [email protected] <[email protected]> on behalf
of
? > Thomas
? >?? > >
? >?? > > Lehmann via groups.io <t.lehmann@...> Sent:
26
? >?? > >
? >?? > > December 2024 22:19 To: [email protected]
<[email protected]>
? >?? > >
? >?? > > Subject: [comets-ml] Unusual brightening of comet C/2023 Q1
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >?????? According to observations by S. Fritsche and myself the
? > comet
? >?? > >
? >?? > > C/2023 Q1 has started a sudden brightening in November.
? > Unfortunately
? >?? > >
? >?? > > our observations are very sparse due to the bad weather during
the
? > last
? >?? > >
? >?? > > two months. Our data suggest a brightening by 1-2 mag between
? > October
? >?? > >
? >?? > > 26th and November 30th.? Latest measurement (green channel):
? >?? > >
? >?? > > 2024-12-23.46 UT, m1=14.1, coma diam. 5'? A more thorough
? > investigation
? >?? > >
? >?? > > by using small aperture measurements is on the way.?? Thanks
to
? > all
? >?? > >
? >?? > > contributors for sharing results and ideas/thoughts to this
list.
? > Merry
? >?? > >
? >?? > > Christmas and best wishes to all of you, Thomas
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >
? >?? > >????? This email and any attachments are intended solely for
the
? > use of
? >?? > >
? >?? > > the named recipients. If you are not the intended recipient
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?