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PostPosted: Mon Apr 30, 2018 12:21 pm 
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A mag 6 nova was discovered in Perseus yesterday by Japanese observer Yuji Nakamura.

The position of the nova (RA 04 43 21.38, Dec +47 21 25.9) coincides exactly with that of another variable star V392 Persei, which was already known to produce small dwarf-nova type outbursts (the most recent of which only reached mag 14). This is somewhat reminiscent of another nova GK Persei. However GK Persei was first observed as a bright (mag 0) nova in 1901 and has since produced a number of smaller dwarf nova type outbursts to around mag 10, these becoming more frequent in recent decades.

Somewhat inconveniently, Perseus is rather low in the NNW sky at the start of the night at this time of the year.

The nova is located roughly midway between Capella and the main stars of Perseus. Robin Scagell is currently working on a newsletter that will be sent out to SPA members and will include a finder chart for the nova.


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PostPosted: Mon Apr 30, 2018 9:52 pm 
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Location: New Farnley, Leeds lat 53.8N long 1.6W
2018 April 30, 21.42 UT. 15x63 binoculars. Rather difficult to identify without an actual field chart for the variable, but IF I HAVE CORRECTLY IDENTIFIED IT, it appears to be fading already and my estimate is mag 7.2 - can anyone else confirm?
Regards, Bob


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PostPosted: Mon Apr 30, 2018 10:28 pm 
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It is fading ... estimated at mag 7.3 at 22:05 UT tonight (70-3 on the AAVSO chart).

You can download a chart for V392 Per from the AAVSO website
https://www.aavso.org/apps/vsp/

This , by default, plots a narrow field chart with a LM of 14.5, but if you use the following link, you'll get a wider field chart with a LM of 9.0

https://www.aavso.org/apps/vsp/chart/?fov=900.0&north=up&orientation=visual&maglimit=9.0&resolution=150&star=V392+PER&east=left&type=chart


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PostPosted: Tue May 01, 2018 8:12 am 
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Location: West Garforth, Leeds
Hi Bob,
2018-04-03 : 22:55UT : 15x70 binoculars
Good clear sky to the NW. Using the finder charts & RA & Dec info provided by Robin Scagell I was confident that I was looking in the right area of the sky. I did struggle to identify the nova, I was expecting it to be brighter than it was. I noted it at mag 7.0.
Regards
Andy


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PostPosted: Tue May 01, 2018 9:47 am 
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Location: New Farnley, Leeds lat 53.8N long 1.6W
Hello Andy, Using the link to the mag 9 AAVSO chart that Tracie provides, I can now say that I correctly identified the nova last night and that I probably used the same mag 7.0 comparison star as Tracie to make my estimate (70-2). To my eyes the nova forms the lower right apex of an isosceles triangle of mag 7 - 8 stars. Given clear skies I wonder if we can continue to follow it.
Identifying newly discovered novae that only get to around mag 6-7 can be tricky. They fade so quickly. We are lucky to have a known dwarf nova here and a chart. I had difficulty last January with Nova Muscae 2018 and it was already down to around mag 7.5 when I picked it up in 8x40s on the 18th.
Best of luck and kind thoughts, Bob


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PostPosted: Tue May 01, 2018 12:31 pm 
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Hi Bob,
I've just printed off the AAVSO chart and compared it to my sketch I made last night and the position of the nova tallies on the sketch and chart. I'm quite pleased with this, as I spend most of the time with the moon & planets. Looking back this is the first nova I've ever looked at
Cliff's image also seems to show what I was seeing.
It would be nice if we had a few more clear nights to follow its progress.
Best Regards
Andy


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PostPosted: Wed May 02, 2018 10:52 am 
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I imaged the nova last night. It appears to be below magnitude 7 now. The session was enlivened by a lovely slow fireball that dropped below Polaris at around 20.10 UT and looked of similar brightness to Venus.

Image

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PostPosted: Wed May 02, 2018 2:41 pm 
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Hi Paul,
I get an empty page with a No Entry sign?

Regards,
David


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PostPosted: Wed May 02, 2018 10:10 pm 
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Location: New Farnley, Leeds lat 53.8N long 1.6W
2018 May 02, 21.58 UT. 80mm f5 refractor x27. Sky transparency fair. Artificial illumination seriously affected the field and made observation difficult. Estimate 90+5 (reliability 3) and 87+3 (reliability 2). Deduced magnitude of nova = 8.4.
Anyone else managed to make an estimate tonight?
Kind Regards, Bob
edited to correct first draft which said "90-5" which should of course be "90+5"


Last edited by RMSteele on Wed May 02, 2018 10:30 pm, edited 2 times in total.

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PostPosted: Wed May 02, 2018 10:24 pm 
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Managed to make an estimate using the AAVSO chart just before the cloud rolled in

21:41 UT V392 Per = 79-5, 86+3 Deduced mag 8.4 (11x80B) class 2 (averted vision for 86 comp)


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