Four supernovae successfully located - NGC4441, NGC4666, NGC4636 & M100
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Scope: 20” f3.6 Lukehurst Dob with Paracorr (fl = 2089mm & f4.1).
Night Vision: PVS-14 with Photonis 4g INTENS.
Eyepieces: DeLite 18.2mm (f5.8 x115).
I was out supernovae hunting last night with three SN targets planned
I am happy to report that I observed 2 out of 3. Here are some notes to help others.
NGC109 / SN2019upw
This one is fairly straightforward as there are few field stars in the area. Once you find the three brighter stars in a triangle then the galaxy is easily seen in the centre. There are 4 faint stars on one side of the galaxy and one on the other. The SN is separate from the core. As I was only using x115 magnification then the split was not straightforward and time was needed to wait and observe for the split to come and go!
This galaxy was really well placed at the zenith at around 1830 last night. The galaxy was not seen but the SN is there. It takes time to find the right spot but there is a field star "3D cube" just above, once you find the cube then you can find the SN. (See stars marked A,B,C,D on my diagram, the Supernova is X).
This is the toughest, there are so many field stars that it is hard to find what to match to the internet images. Anyway, it turned out that I was looking in the wrong place but the stars I drew do match the images so I was just a small way off.
Look carefully at my sketch and there are two rows of field stars (the 3+2 and the 3, the middle star of the lower 3 is a double), if you can find these two rows of stars at the eyepiece then the SN is in-between these rows as shown by the blue box (added this morning). I was looking further up in a tight cluster of stars where the tiny galaxy appeared to be (my mistake!).
This has been a bit of a project. Last year I worked out that my 200mm Canon F2.8 lens and ASI1600 would frame the whole of the Veil complex quite nicely. I captured Ha and OIII data for the east and west nebulae with a Tak FSQ 106 and added this into the widefield image. Although the Tak data had to be shrunk down it did add a bit of extra resolution where it was needed.
The difficulty for me has been the processing. I have found it really difficult to tease out the faint wisps of detail and have tried the usual routines of micro contrast adjustments using curves along with Scott Rosen's Screen blend/mask inversion method but the results weren't great owing to the close proximity of faint and bright nebulosity. I'd heard about the PI process tool for removing stars, Starnet, so loaded this and had a rare foray into PI. This proved very helpful. It was a luminence created from Ha and OIII using the 200mm lens with the Tak data mixed in. Then the starless layer was added in PS with the screen blend mode at 50% opacity. The nebulosity detail was so well preserved I didn't need a mask. After blending I reduced the stars a bit more using the starless layer again and darken as the blend at 50%. I should really unleash some of the stars to add a bit of "punch" but I've wrestled with this data enough for now! I plan to use it further as I look deeper into the Gorgon that is PixInsight!
Telescope: Tak 106 for E and W veils. Canon 200mmL lens
Camera: ZWO ASI 1600 pro mono cmos, Gain 150, offset 50
Filters: Baader 7nm OIII and Ha
E+W Veil 10x30 mins each channel for each nebula. Whole complex 50x5mins for each channel
Captured with SGP, calibrated, aligned and combined with PI, processed mainly with PS but PI for Starnet. Ha mapped to red and OIII to both blue and green
After spending a couple of hours on bright galaxies and comets, I turned my attention to Supernova (as the Plough finally appeared from behind the shed roof).
First up was SN2018hna in UGC7534 (mag 14.9) in Ursa Major.
- I had observed this one already so I was on a "confirmation" mission. I soon located the oblong of stars (at the centre of the images), one corner of this oblong is the SN. I spent some time and noted another faint close-in star (to confirm on the image today) and everything matches up.
- With the 55mm Plossl and Night Vision the core of UGC7534 really lights up and all you see of the galaxy disk is a smudge to the south of the core.
Next up was a new SN for me. SN2019va in UGC8577 (mag 16.7!). Its located near the arm of the Plough.
- With the 55mm Plossl, I soon matched the star patterns to my sketch (that I made from the images earlier). There was no sign of the galaxy but there are other visible UGCs in the fov (to add confusion). There was no sign of the SN.
- I swapped in the Panoptic 35mm (x60 magnification) and the fainter stars got a little clearer. I was now sensing a disturbance in the centre of the fov which must have been the galaxy disk. A point of light blinked in and out three or four times. I noted the position based on the star pattern and was able to confirm the blinking dot in the correct location.
Hopefully, SN2019va will get a little brighter by the time I get another shot.
I often love to play youtube lectures in the background as i work on my home improvement projects, only problem with that is many times my attention gets so focussed on the computer screen that i fail to see paint dripping from my brush onto the carpet, that did happen!. Anyway, here's a great lecture from the Perimeter Institute for Theoretical Physics which is just a couple hours drive from my home about the weirdest stars known, some fascinating facts here with a dose of humour.
Date: Thursday 8th March 2018 2150-0210am Scope: 20” f3.6 Lukehurst Dob with Paracorr (fl = 2089mm)
Waiting for a Sign!
Signs were that I may get out for a session (after a two week barren spell). Skies were cloudy at 8pm and the cat came in a little on the damp side so I was a little disheartened.
I got up and looked outside at 9-30pm and the sky was clearing so I started to get ready…
Not a Good Start
Once setup and aligned, I decided to start with some comets. Using Sky Safari I found three well placed comets overhead:
C/2015 O1 PANSTARRS
C/2010 U3 Boattini
I failed to locate any of them and so that was a depressing start.
Time for a Nebula!
I switched to planetary nebulas. Fitted the O3 filter and headed for the Eskimo in Gemini. Using both the Ethos6 (x348) and Ethos8 (x250) I could see the central star surrounded by a bright circular disk which was itself embedded in a dusty halo. The circle was bright with the E6 but harder with the E8.
I headed over to the Medusa and was surprised by its size. I ended up with the Ethos13 (x150) where I could see the large curved leading edge. The actual finer detail was hard to tease out and I tried both the O3 and UHC to try to see more. I found the UHC best but this was a difficult target and I felt like I had not seen as much as I should have?
Now onto the Owl. E13 unfiltered. A nice circular cloud was seen with the two big black eyes coming & going from view. I tried the UHC and it improved but I have seen it better.
Six Supernova Anyone?
Having spent some of my spare time (in the last two weeks) setting up a “supernova” observing list in Sky Safari. I asked the app to highlight my list and was presented with a clear galaxy hopping trail ready to be explored…
I also made pre-prepared sketches of the SN galaxies and surrounding star patterns so I have something to refer to as I try to orientate myself with the sky region.
NGC3158 & SN2018aaz – After checking my sketch, I quickly had the galaxy centred in the E8. It was a nice size but I could not see the three close in dots from my sketch. Switching to the E6 (x348) revealed more of the smaller stars and I matched the star pattern. Inside the galaxy halo I could see two dots. One of these could have been the SN?
UGC5049 & SN2018pc – At my first attempt last month, I got this SN easily with the galaxy showing easily on that night. Two further attempts had failed to reveal even the edge-on galaxy! Tonight I could see the galaxy and sure enough there was the SN tucked nicely into the centre. SUCCESS
NGC2746 & SN2018iq – With the E8 loaded, I quickly located the galaxy next to a star. There was no sign of the SN until I swapped in the E6. SUCCESS
NGC3367 & SN2018kp – I have had a couple of goes at this SN already with no success. My shed wall was obscuring my view on those occasions but tonight I seemed to drop lucky and I could get a good view of it. I tried with E6, E8 & E10 eyepieces. The star pattern was easily matched and I had learned a lot from my previous attempts too. I think I finally did glimpse the SN but it was only brief glimpses of a “second dot” in the right place within the galaxy halo. The halo was showing particularly well last night (maybe the extra magnification of the E6?). SUCCESS
NGC3384 & SN2018yn – I quickly located the host galaxy and then discovered that I had not made a sketch of what to look for! I made a star chart of what I could see ready for verification this morning instead. The galaxy was a good size and showed a nice halo. I managed to see a dot within the halo. Looking at the images this morning it seems more likely that I saw the core than the SN as the core is much brighter on the images.
NGC3941 & SN2018pv – Onto the brightest of them all. I have seen the SN several times already and I must say that it was very hard to split it from the core last night (harder than on previous visits). Even with the E6, the centre looked more like a dual core. A “clear gap” was not seen. SUCCESS (almost)
Oh well, four from six ain't too bad.
Worthy of a Mention
I spent the rest of my session taking in galaxies from Ursa Major down to Leo. Some targets worthy of a mention were...
NGC3163+3159+3161+3150+3151 – Five galaxies in the FOV. All of them pretty easy to see. A group of three and a group of two. Ethos8 (x250). A very nice vista.
NGC5350+5353+5354+5355+5358 – Another five galaxy view! This view had the bonus that two of them were interacting with each other. Great!
M87+4478+4476 – A nice “curvy” trio of bright galaxies.
Forever the Optimist
Lets hope for a few more clear nights as the new moon approaches!