Comet C/2023 A3 Tsuchinshan-ATLAS

[verreli]

A catchy name for what could be a great comet.  Predicted and on track to be better than mag 0 with a boost after perihelion due to forward scattering making the core daylight visible.  Best from the southern hemisphere in September before dawn and northern hemishere in October after sunset.  May have a big bright tail making it awesome for photos.  Watch this space.

[scotty1]

Hale-Bopp C/1995 O1 during 1997 was amazing , was lucky to be around for that one. Before Hale-Bopp I hadn't seen a Comet. I can't remember Comet West in 1976, i may of seen it by chance...

 

More info on Comet C/2023 A3 Tsuchinshan-ATLAS 

 

https://www.skyatnightmagazine.com/advice/comet-c-2023-a3-tsuchinshan-atlas

Edited April 20 by scotty1

[Taman]

I've just seen an image on Astrobin, it already has a nice tail. Currently moving slowly through Virgo, so should be observable once the Moon has gone.

https://www.astrobin.com/aufl8o/

[PeterStudz]

12 hours ago, scotty1 said:

Hale-Bopp C/1995 O1 during 1997 was amazing , was lucky to be around for that one. Before Hale-Bopp I hadn't seen a Comet. I can't remember Comet West in 1976, i may of seen it by chance...

 

More info on Comet C/2023 A3 Tsuchinshan-ATLAS 

 

https://www.skyatnightmagazine.com/advice/comet-c-2023-a3-tsuchinshan-atlas

Hale-Bopp is the only comet that I’ve seen naked eye. I wasn’t into astronomy back then, but even in a light polluted areas it was clear, with a tail, like drawings and paintings of comets I’d seen. You couldn’t miss it. 

[Space Hopper]

Lets keep our fingers x'ed for this one.

Big 'if'  though, will it make it round the sun in one piece ?

A lot of these promising comets that the media like to hype up often end up in bits before we get to see them.

I should have a new camera by then as well   (Perihelion is September 28) 

[scotty1]

11 hours ago, PeterStudz said:

Hale-Bopp is the only comet that I’ve seen naked eye. I wasn’t into astronomy back then, but even in a light polluted areas it was clear, with a tail, like drawings and paintings of comets I’d seen. You couldn’t miss it. 

So far I can remember Comet Wirtanen as just naked eye visible. Neowise was clearly visible by eye, and I could just about see 12P Pons- Brooks at the end of March. 

Comets are fascinating and scary too. 

[verreli]

On 21/04/2024 at 10:03, Taman said:

I've just seen an image on Astrobin, it already has a nice tail.

 

That's a strong tail for a comet so far out.  Very promising.  I just happen to be in South Africa in September when it should be naked eye visible and have booked my flight seat so I can see it from altitude.  I have a good feeling about this one.  Lots still to find out.  What colour will it be?  Will it be twin tailed?  If the projection in Stellarium is anywhere near accurate, it's going to be an amazing sight.

[scotty1]

What size is the core of comet A3 Tsuchinshan-ATLAS i haven't seen any information. 

Edited April 25 by scotty1

[pjsmith_6198]

I was able to observe C/2023 A3 Tsuchinshan-ATLAS  through my 12" dob on May 1.    It was still a bit faint,  https://theskylive.com/comets estimated it's magnitude at 10.2 and coma size as  2'.    The coma was pretty condensed so it wasn't difficult to see. with a 20mm EP , but it was better  with my 10mm and 7mm EP's.    With the  higher magnification the false nucleus was visible and almost  stellar.   It didn't have much if any response to my comet or Swan filters.   It was bright enough to be visible an iPhone photo.  I just used the default settings.   See below.     The comet wasn't as bright as shown on the photo.  Also from the photo, it looks like a small tail is visible.   I didn't see that visually.

On May 20 the comet will be in the same 1 degree FOV as quasar 3C 273.   I think would be quite challenging to see them both at the same time because 3C 273 requires high magnification to see.  But wee can try.

Phil

 

[Armand Popa]

I also observed the comet visually, through my 8" dobsonian. I followed it for 3 nights, on April 27th, 28th and 29th. It was best seen on April 28th, when besides the condensed coma, there was also an eastward elongation, the comet looking most like a water droplet.  The best image was obtained with the Lacerta Uwan7mm eyepiece. 

[John]

Caught Comet C/2023 A3 Tsuchinshan-ATLAS with my ED120 refractor this evening. Seems to be around magnitude 10 and situated in Virgo around 2/3rds of the way between Porrima and Heze, close to a faint triangle of stars. Does not jump out with this aperture at 64x and could be mistaken for a galaxy, especially in this part of the sky. A faint, rather small fuzzy elongated patch of light.

Nice to see it though 🙂

Edited May 4 by John

[Geoff Lister]

The sky was clear for me too. This was from my Seestar S50 this evening, direct from my tablet, without any post-processing. The S50's plate solving was unhappy with the fairly empty star pattern, so I used Porrima for alignment.

The "Mark" function could not find an obvious target, and a Stellarium search for "UGC 8262" just placed a cross about where the fuzzy blob is above-right of the comet.

Geoff

[pjsmith_6198]

On 04/05/2024 at 17:36, John said:

A faint, rather small fuzzy elongated patch of light.

Yes that's what I saw.   So  the brightest comet of the year  starts off as a small faint patch of light.   I think it would be pretty cool to follow this  comet from faint blob to maybe a mag 0 comet.    Whenever I observe this comet I'll report what I see here. date, the  brightness/magnitude, coma size, tail if any,  and whether it responds to filters.    If enough people pitch in we can  make a magnitude graph  similar to here http://www.aerith.net/comet/catalog/2023A3/2023A3.html  .   Photos and sketches would be a good thing to include.   As Geoff's  photo is infinitely better than my iPhone shot.

 

Phil

 

[John]

Got this comet with my 4 inch Vixen refractor tonight. Quite challenging still with the smaller apertures ! Short report here:

https://stargazerslounge.com/topic/385898-what-did-you-see-tonight/?do=findComment&comment=4484674

 

Edited May 8 by John

[Nyctimene]

Spotted the comet for the first time this evening with the 8" f/4 Hofheim traveldob under 5.0 NELM/ 21.08 SQM-L skies, slightly hazy. Easy to find close to Porrima; at 44x mag (18/82°) with direct vision. Clearly elongated, with a short tail pointing E, and a small false nucleus (mag 88x) in the W part of the coma. Coma diameter of about 1.5-2 arc min. Brightness around 9.5 - 10 mag, easy to compare with the 9.6 mag gx NGC 4753 just 2.1° to the SW. Already now a short tail - seems promising for this autumn.

Thanks for reading

Stephan

[John]

Pushing things a bit tonight with just the 70mm refractor. After some careful searching I did manage to spot Comet C2023 A3 with the little scope. Not far from where it was last night. I could see stars down to magnitude 10.7 with direct vision at around 80x magnification but the comets elongated fuzz needed a little averted vision to get a sure and repeatable sighting. Not the ideal scope or skies for keeping tabs on a small magnitude 10 comet but there you go ! 🙄

Not surprised that @Nyctimene / Stephan (post above) is getting a somewhat better view with his 8 inch scope though 🙂

 

Edited May 9 by John

[Geoff Lister]

Last night, there was thin high cloud, but I was able to image C2023 A3, again after aligning the Seestar with Porrima. The image developing on my tablet's display seemed to take longer to form, than a few nights ago; probably due to the thin cloud. This time, I had not centred the Seestar on the comet, but the recorded image included the target name.

Geoff

[John]

3 hours ago, Geoff Lister said:

Last night, there was thin high cloud, but I was able to image C2023 A3, again after aligning the Seestar with Porrima. The image developing on my tablet's display seemed to take longer to form, than a few nights ago; probably due to the thin cloud. This time, I had not centred the Seestar on the comet, but the recorded image included the target name.

Geoff

That confirms that I was seeing my "averted smudge" in the right place at least 🙂

[Harry4thestars]

I am tracking it now and will continue until it gets close to earth. It's very interesting event. 

[Geoff Lister]

Last night, there were clear skies to my north, but a big bank of cloud advancing northwards from the south. I set up my Seestar, on the offchance that the cloud would thin. Eventually, I was able to see Spica playing hide-and-seek in the thinning cloud, so I was able to get a rough alignment (the subsequent 3-point alignment failed). I did a GoTo to C2023 A3, and the Seestar eventually acknowledged that it had found the target. So, I started imaging. The clouds continued to break-up, and I was starting to get fewer discarded frames due to "too few stars". This was the result:-

Although the readout shows 22 minutes, the total time was more like 50, with the field rotation effects being visible in the top-right of the frame. Stellarium notes that the star just above-left of the "A" of the "... n-ATL ..." label is, A 2487 (HIP 59970 A), magnitude (with airmass reduction) of about 9.1.

Geoff

[lunator]

Geoff well done on beating the conditions. 😀. It's a very good pic.

I must try and track this comet down. 

I had a quick at the data for A2487. It is a classic Aiken double. 8.9 &12.5 magnitude and 1.9" separation. Not for you average scope....

Cheers

Ian

[Geoff Lister]

This evening, even more cloud. The comet's core is definitely showing 2 distinct parts, with a greater separation than my previous image. The 23 minutes of recorded images took over 90 minutes with the other images discarded due to the clouds. The bright star, bottom right of the image, is "10 Vir".

EDIT: Having slept on it, I think the effect was due to movement of the comet with respect to the background star-field, and the capturing of data during gaps in the clouds, towards the beginning and end of the 90-minute total imaging period.

 

Geoff

Edited yesterday at 06:02 by Geoff Lister
Revised conclusion about double core in image