Glimpses of Comet 2015 V2 Johnson

[Tinderboxsky]

I have been waiting for a clear night with the Moon looming brighter and brighter by the day and threatening to spoil the party. Tonight held some promise so I set up hoping for the best.
The clouds parted sufficiently at about 8.00 for me to do the simple star hop from Izar to the spot adjacent to SAO 83458 in Bootes. Comet Johnson was immediately obvious as a faint diffuse patch but disappeared almost immediately behind some rapidly moving cloud.
Fifty minutes later the clouds parted and I had enough time to get a reasonable look. Seeing was at best 3/5 and transparency about 5/7 and the Moon was obviously interfering as the sky was not the usual inky black that I have here at Tinderbox.
All I could see was a broad faint diffuse round patch with a hint of brightening towards the centre. The central spot brightened temporarily as moments of better seeing came and went. There was a faint star of about mag 10 just on the edge of the faint patch. Inevitably more cloud rolled in and I retreated indoors for the night.
I will try again over the next couple of nights to get an appreciation of the Comet's motion but fear the brightening Moon might spoil the party.
Scope: Vixen NA140SS with LVW13 giving 62x on TRex mount.

Steve.

[Tropo-Bob]

I had a look tonight with my 100mm Vixen. At 27x, it was easily visible, but has dimmed somewhat. At 50x, it was still visible but not as easily to find and not as distinct when found.

Comet Johnson currently lies about 2 degrees beneath and a little to the north of the very attractive double ADS 9247 (14H23, +8.27). This is the first time I have seen this double, so that was a good, unexpected bonus.

[tonybarry]

On the 3rd June, at Penrith Observatory, I obtained some images of Comet C/2015 V2 Johnson; 20 second exposures over a period of 11 minutes. Meade LX90-10" and Flea 3 monochrome camera.

I attach the resultant stacked image, centred on the star field. The comet motion is clearly evident. The companion stars to the comet have their magnitudes annotated, and a local bright star has its SAO number also annotated.

Regards,
Tony Barry
WSAAG

[Tinderboxsky]

I was out tonight too, but not till well after nine. By then the bright Moon was well up and there were bands of very fine high cloud moving across.

Your position description made it very easy to find the spot. Once there and settled, Comet Johnson popped out as a very faint hazy patch with very slight brightening towards the centre. In moments of better seeing a brighter centre was visible. My initial observation was at 33X with a Panoptic 24. For me, the better view was at 62x (LVW 13) as the background Moon lit sky was slightly darker giving better contrast.

I have an observing night this Saturday night and hopefully we will get a better view without the Moon interfering even though it is fading.

I agree, ADS 9247 is an attractive double.

[Suzy]

I'm yet to get this one, so I'm happy to hear that it's still visible despite the Moon interference and some clouds lurking. As soon as the rain stops and the clouds go away along with the Moon, I'll have a look.
With my 10" dob using my 14mm Denkenmeier eyepiece, I get 85X magnification which I've found to be the best for observing comets.

Eeek I just took a look at COBS and it's currently estimated at mag. 8.9. I don't like my chances with light pollution thrown into the mix :(.

[doppler]

Definitely getting dimmer, a pity because its well placed for evening viewing. Here's a pic from the 12th of June.
10" Skywatcher newt, 10 x 60 sec at iso 1600.

[Tropo-Bob]

Still easy enough when viewed tonight with my Vixen 115mm from 30x to 60x. It is dimming but interesting to follow it when the weather permits.

[Tropo-Bob]

Visible in 80mm at 30x tonight. It is moving roughly 1 degree per day.

[Tinderboxsky]

I was out last night at the Astronomical Society's observing site which has good dark skies to the north. Comet Johnson was a fine sight. I was surprised by the size of the coma. The fine haze appeared to be about 30 arc mins across, if not more, with a definite gradual brightening (but still quite faint) towards the centre. Averted vision revealed a very small, almost point like central nucleus. The bright central spot and surrounding coma glowed quite clearly when moments of better seeing washed over. Best views were at 62X with seeing 4/5 and transparency 6/7.

It was the first comet sighting for a number of the people present, so a real topic of conversation on the night. We had to be patient, though, with cloud stubbornly hanging blocking our view to the north for a couple of hours.

Scope: Vixen NA140SS with LVW13 giving 62X on TRex mount.

[Tropo-Bob]

I observed Comet Johnson last night with 115mm & 70mm telescopes.

Found it with the 70mm (Williams Optics F6.3) first using 17x. It could easily have been swept past, but I knew exactly where to look. It was better at 39x.

With the Vixen 115mm, at 60x, I had the impression of both a reduction in the size of the coma and the overall brightness. In the centre of the coma, my impression was that it was brightening to a star-like point, but somehow failed to make it.

[Tropo-Bob]

Spotted Comet Johnson tonight with Vixen 102mm. At 26x it was obvious, but fainter than last week. It was somewhat more difficult at 50x.

[Tinderboxsky]

I did a quick star hop to Comet Johnson after my Jupiter observations this evening. The comet has faded slightly since my last observation on 21st. The coma is smaller. There was still some brightening to a tight bright central spot. Best view was at 62X.
It is certainly climbing quickly in the sky and it will be interesting to see how long it can be seen as it continues to fade and the Moon starts to interfere.
Scope Vixen NA140SS on TRex mount and LVW13 giving 62X.

[Tropo-Bob]

Found tonight with my Vixen ED 102mm. Using a 25mm EP (26x), the Comet was faint but still spread out into a diffuse patch. It is the better part of a magnitude fainter and smaller than when I last saw it.

With an 11mm EP, I could barely see it using direct vision.

To find, draw a line from Jupiter up to Spica and continue on straight for the same distance and a third, and U will be near Comet Johnson.

[Tropo-Bob]

I viewed Comet Johnson with an 80mm, F6 triplet tonight using 19x and 44x.

It has become quite faint and continues to shrink in size.

[Tropo-Bob]

I have taken advantage of an unusually clear evening to view the Comet with a 127mm F9, ED Meade refractor.

Though my view was better than my last sighting, it is now a faint object. Many lesser globulars now appear brighter.

The coma seem to brighten towards the centre but there was no starlike point or tail to be seen.

The Comet is near Pi Hydra, about 1 degree above (East) and about 3 degrees to the north.

[Tinderboxsky]

A series of good observation Bob. I have been totally frustrated by the weather unfortunately. Still hopeful for another sighting before the comet fades from sight.

[Tropo-Bob]

Thanks Steve, its good to hear from You.

I had to pull out some ordinary gear to get to my mount tonight and I thought I would check if the Comet was visible with that also. (I don't want newbies to think they need expensive equipment to see this.)

So I also had a quick look with an achromatic, F6.5 100mm using 2 cheap plossls (25 & 20mm EPs). The Comet was clearly visible, but was faint of course.

[Tropo-Bob]

This is becoming a familiar story: Found the Comet, but it is smaller and fainter than before.

Actually, I failed to find it with my 80mm triplet, so I tried with the Vixen 100mm ED at 26x. The Comet was just above (East) of a 9th Mag star and was difficult to find. I realised it was near the star and thought that it would be visible with inverted vision if I looked directly at the star. I tried that for about 2 minutes,but It was not visible.

I had to look away from the star and then with inverted vision, I could see the small, faint comet nearby.

[Tinderboxsky]

Clouds are my familiar story at the moment!

Cloud Free Nights is forcasting a clear sky tomorrow evening. I will keep my fingers crossed as it would be nice to get one last sighting. My last observation was way back on the 25th June!

[Tropo-Bob]

I saw this tonight with my Vixen Ed 102mm (F6.5) with 25mm & 15mm EPs.

It resembled a face-on galaxy, being faint and having a little bit of size but most definitely much fainter and smaller than seen in my previous viewings.

It looked to have a star-like centre, but I suspect that may just be a faint star in the same line of sight.

[Tropo-Bob]

I viewed this with my Vixen 140mm refractor and tonight and did not see any starlike point. This tends to confirm my opinion from yesterday's observation that the point, which I saw was just a background star. I used 25, 18 and 14mm EPs.

The Comet was in the same field as the bright star Omicron Centaurus. However, as misfortune would have it, I became confused with my star hopping and it took me about 20 minutes to find the comet. If anything, having the bright star in the field also made peripheral viewing more difficult.

[Tinderboxsky]

I am following and enjoying your reports Bob.
I have the location maps ready for star hopping but am completely frustrated by the lack of clear skies. Tonight was looking promising but scudding cloud and fine driving rain appearing from no where has put and end to that. We have had fresh snow on the nearby mountains.
I hope I can log one last observation before it dims out of sight.

[Tropo-Bob]

Thanks Steve. Before joining this forum, I thought it was only me that suffered from terrible skies!

I see from the predictions tonight that the comet will pass very close to Omnicon Centaurus during the later part of this evening.

See: https://theskylive.com/comets

[Tinderboxsky]

Yes, I had noticed the predicted close encounter. It is currently clear here, so we will see what tonight brings. Hopefully Omnicon Centaurus is not too bright to drown out the faint coma.

[Tropo-Bob]

Viewed tonight with my 115mm Vixen with 15mm EP.

Hard to see of course, but was outside of and on the northern side of the 'haze' around Omnicon Centaurius.

[DeepSkyBagger]

OK, I have to admit to being a little confused here. Comet Johnson passes no closer than 35 degrees from omicron Cen. On 13/8, it more or less passed in front of 4.0 mag SAO 205839 - is this the star you mean?

Please forgive if I'm being dim.

[Tinderboxsky]

Hi Patrick
Yes, 205839 was the star that Comet Johnson passed very close to on the 13th. I think your reference to a 35 degree separation from Omnicon Centaurus should probably have been 3.5 arc minutes or less.
I have just come in from observing the comet - it is now very close to 8.63 mag star SOA 205900. It will pass in front of this star later this morning, our time.

[Tinderboxsky]

At last, a night, without other commitments, and clear skies except for some high cloud low to the north.
Comet Johnson was clearly visible as a broad, very faint, diffuse glow. Moments of better seeing revealed a slight brightening in the central area, but no central bright spot. It is now close to 8.63 mag star SOA 205900. It looks as though it’s path will take it directly in front of this star early tomorrow morning.
True to form the high cloud to the north had been growing as I searched for and observed the comet. Within 30 minutes of my observation, the sky was completely covered by thin high cloud! The same fate stopped me in my tracks for the last 3 nights - clear at dusk but clouded out be the time I had my scope out ready to search for the comet.
Well, at least I have caught a final glimpse of Comet Johnson before it fades from view.
Vixen NA140SS and LVW 13 giving 62X gave the best view.Seeing and transparency were only average.

[DeepSkyBagger]

Hi Steve. You keep typing 'omnicon' is that a misspelling of 'omicron', or another star altogether? Comet Johnson passed only 35 degrees (no mistype, I don't mean 3.5') from omicron Centauri. My charting software puts Johnson on top of SAO 205900 as well, so we're talking about the same comet at least!

Patrick

[Tropo-Bob]

Originally my bad with the spelling of Omicron. Also, I took the symbol from my "Bright Star Atlas" to be Omicron, but again, I may be mistaken.

[Tropo-Bob]

Yep, I am mistaken, as the bright star that Comet Johnson passed a few days ago was not Omicron. When I look more carefully, the star has "b" marked against it in the charts. There are many bright stars in Centaurus, so I can only assume that all the Greek letters were used before this star was designated.

[DeepSkyBagger]

Ah! Right, thank you Bob. I thought I was going daft for a bit.

Patrick

[DeepSkyBagger]

For what it's worth, here's an observation I made of the comet back in May, when it was above my horizon!

Located just over 2° from ε Boo at the time of the observation, it was washed out in the twilight. The head was fairly large and round. It grew gradually and then sharply brighter towards the centre. A twinkly stellar nucleus was occasionally visible. There was a persistent suggestion of a tail, long and thin, heading away from the head towards the south-east.

Cheers,
Patrick

[Tinderboxsky]

That’s great Patrick. By the time of my first observation on 1 June here, Comet Johnson had moved well past and to the south of ε Boo.

I like your drawing. As they say “a picture paints a thousand words”. How long did it take you to complete the drawing? I have wanted to try a couple of times but just have not made a start.

[DeepSkyBagger]

I make a rough sketch at the eyepiece. That would take 5 minutes or so, then usually on the following day I'll make the full drawing. It's pencil on white paper then inverted using an image processing package.

I've been sketching deep-sky objects for over 40 years. In fact, I've sketched just about every DSO I've ever seen, apart from open clusters. I just write descriptions of those, usually. The same techniques apply to comets. I've only made a dozen or so observations of comets though, as opposed to something over 1300 DSOs.

[Tinderboxsky]

Last night was clear with above average seeing and good transparency, so thought I would check in on Comet Johnson.
It was projected to be just next to a near 10th mag star HD 131186.
To my surprise I could just make out a very faint smudge of light surrounding the star with it being slightly more distinct with averted vision.
Tonight the comet is predicted to be between the two close stars HD 131488 (8th mag) and HD 131435 (7.15 mag), which is a very easy star hop from Kappa Centauri.
I’ll have look tonight if it is clear, but I suspect that the glare from these two stars may be too much for the very faint comet.
Vixen NA140SS with LVW13 giving 62X and 2.26 exit pupil.

[Tinderboxsky]

Last night was clear with average seeing but quite good transparency So, I thought why not give Comet Johnson one last try.
The comet had moved between and past the two close stars HD 131488 (8th mag) and HD 131435 (7.15 mag) and was residing in a very faint star field with the relatively bright Kappa Centaurus lurking nearby and in its path.
The comet was visible with averted vision as the faintest broad smudge of light using a Panoptic 24 (33X and 4.25 exit pupil) but very difficult to retain sight of when looking directly at it. Kappa Centaurus needed to be kept out of the FOV.
Switched to an LVW13 (62X and 2.26 exit pupil) and the comet was easier to spot with averted vision and I could just hold sight of it looking directly at it.
I think this will be my final glimpse of Comet Johnson. It is forecast to be another clear night tonight, but the comet will be swamped by Kappa Centaurus. After that I think it will be beyond my scope as it fades further, some poor weather and an emerging Moon interferes.