开云体育

On 12/29/24 04:33, Maik Meyer wrote:> You may use With the minor note that, because this is a spacecraft-based observation, you'll have to tell MPC where the spacecraft was at the time of the

Hi JJ, I used the word debate in the context that the apparent magnitude of this comet is in debate, not your method of observing or derived results. I do not want to have an argument about this.I

Alan, Michael, all, ( Sorry for the length of this text ) This thread reminds me of several discussions from the past decade on the old "Visual vs. CCD" debate ... Quoting Alan words : " I was

Hello dear, That's it ! Comet 2022 L3 Atlas, Thank you Maik, Sam and Peter, Christophe

Hi Christophe, Using a geocentric Horizons ephemeris, Comet P/2022 L3 (Atlas) was at 02 12 03.40 +23 40 42.1 on 2022 11 16.685 UTC, quite close to the position you've given below. Peter J95

Hi Christophe and Maik, I was about to reply that this is C/2022 S4 (Lemmon) which is several magnitudes too faint (close to magnitude 20) but passes over the exact same part of sky (down to the

Hello Christophe, this is P/2022 L3 (ATLAS). Magnitude fits nicely. You may use https://minorplanetcenter.net/cgi-bin/checkmp.cgi Regards Maik

Hello happy comet enthousiasts ! I was performing some photometry on a variable star (Hip10272, in Aries) in some TICA TESScuts, sector 58, when I came upon a quite nice comet slowly crossing the FOV,

Dear all the outer coma is there and 3', the image from dec. 28 is a deeper (12"/4 15x130 seconds) under best sky conditions. However, this cannot be seen visually. Best regards Michael ------

Dear all, I was debating whether or not I wanted to wade into this again, but I guess my curiousity got the better of me. I’m attaching two stacked versions (3 x 180 seconds) of all the images I

Thomas, Denis, Peter, Jakub, all, Some recent further visual data : C/2023 Q1 (PANSTARRS): 2024 Dec. 28.82 UT: m1=11.7 (AQ), Dia.=6', DC=1/, 20 cm SCT (77x). [ Faint, large and very diffuse outer

Dear All, For the moment i measure magnitude 16 using SDSS r' filter. Uncalibrated images. PhotAp 6.1arcsec ________________________________ Sent: Saturday, December 28, 2024 2:19 PM To:

After taking a another look at Michael's picture, I just realized from the star on the upper left that the image may have been sharpened with a high pass filter, which may be making the spine look

The comet's absolute magnitude is ~7, so it's technically brighter than the Bortle limit for all q. Of course, it's also dynamically old, but with a dynamical age on the order of only ~1 orbit, and

Hello Denis, The answer to most of you question is easy. This usually happens to weak and gasseous comets. The activity goes gradually up, but we cannot see the product as the coma surface brightness

Hi David, comet photometry from images is usually done by measuring fluxes both in the comet region and outside. The background level obtained by the latter is then being subtracted resulting in the

Skyglow? If coma diameter is 4' that's 45,000 sq "I think I saw a figure of 21mag per sq arcsec?So airglow alone would 'add' 11.6mag i.e. a patch of dark sky 4' in diameter is mag9.4? Is my maths

Hi Denis, very good questions ... I really don't know you can visually see such faint features. It would require really low magnification and huge aperture and pristine skies and exceptionally

Hi Thomas and Denis, I imaged C/2023Q1 earlier this morning with my 315mm reflector from my remote site under approximately SQM 21.7 skies. I stacked 20 x 60-sec exposures. Comphot gives mag 15.55

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