Why are comets like buses?

[Ross Wilkinson]

Famous comet-spotter David Levy used to say:

But my experiences this year suggest that they are more like buses - you wait ages for one and then two come along at once!

I'd only had one comet so far in 2025 - and that was back in January! But then on 11th October, I managed to spot C/2025 A6 Lemmon (available in other flavours too?) low down in the NW. It was only visible for a short while, just above the shed roof and I could see it as a "faint fuzzy" with my 10x30 Canon IS binoculars.

Then I had to wait until the 25th for the next clear night and by this time the comet was bright enough (4th magnitude) that I could make out some of the tail too with my binos. But it was still too low in the sky to reach with my telescope imaging system.

However by this time C/2025 R2 SWAN was visible too: much better placed (in Aquila), so I could get it with my 80ED 'scope. I noted when I powered up the mount it showed the date of its last use: 2nd January. But I'd remembered how to set it all up and had just got the 'scope focused and aimed when the clouds rolled in! Happily, this was just a brief interruption and then apart from one pause when the neighbours' dog came out and set off their floodlight for a couple of minutes, I managed to catch 70x 20-sec exposures with my Sony NEX5R camera. So now I'll need to remember how to do the processing in Siril...

[Ross Wilkinson]

This is my image of C/2025 R2 SWAN from last night, processed using the latest version of Siril: I made separate stacks of the comet and the background stars and overlaid them using GIMP.

It's composed from 48x 20-sec images from my NEX5R camera on the 80ED 'scope operating at f/4.8

[Ross Wilkinson]

I've managed to see C/2025 A6 Lemmon three times with my binoculars over the last month, but it's always been to low down for my usual imaging systems.

However last night just before 6pm I had a go using a fixed camera clamped to a fence-post. I wasn't sure if I'd get the comet above the roof of the house opposite, but it proved to be a tall tree a couple of streets away that was the problem:

The trailing is a result of using 15-sec exposures and this is a sum of four images, using an old Pentax 135mm lens on my Sony NEX5 camera.

[Ross Wilkinson]

Well, I've now had a third comet within three weeks!

This latest one is C/2025 T1 (another "ATLAS"), which is a fresh new discovery (from 11th October). 

It's about 10th magnitude, but well-placed for evening observation, in Hercules.

That's a stack of 33x 60-sec with my Mx716 camera on the C8 scope, operating at f/3.5.

Even though I'd not had that 'scope set up since 2nd January, it all went together well, and I've even remembered all the processing steps in IRIS!

On Sunday, 26 October 2025 at 12:08:30 UTC Ross Wilkinson wrote:

[Ross Wilkinson]

Now up to four, since 25th October!

C/2022 N2 PANSTARRS is only 13th magnitude, but in a convenient part of the sky (in Aries).

It looked like a clear night as I was setting up at 7pm, but within an hour it had clouded over and started to drizzle!

Nonetheless, I did manage a detection in the time available:

That's a stack of 20x 30-sec with the Mx716 camera on the C8 at f/3.5.