PDA

View Full Version : Object of the Week June 2nd 2019, K 1-14



obrazell
June 2nd, 2019, 08:39 AM
Kohoutek 1-14

Also known as PN G045.6+24.3, PK 045+24.1

RA 17h42m36.8s (2000)

Dec +21°27'02" (2000)

Size 47”

Mag 15.10

Mag CSPN 16.1

Whilst examining the POSS prints in 1963 Lubos Kohoutek discovered a number of new planetary nebulae and this
object in Hercules was number 14 in his first list. The objects were classified based on their shape and relative
brightness’s on the red and blue plates. K 1-14 is a rather nice ring shaped planetary nebula with limb brightening
and some internal structure. If the central star is the blue object then it is no longer in the centre of the nebula
and this could be because K 1-14 is thought to be an old planetary nebula starting to interact with the interstellar
medium as it ages. The local ISM is slowing down the expansion of the nebula but the star is not affected and is
moving away. ). K 1-14 is surprisingly bright in the GALEX ultraviolet images which suggests it may be quite a high
excitation nebeula, which would be at odds with it being old. It is thought that the central star of K 1-14 is probably
a visual binary. As perhaps suspected there is not a lot of research on K 1-14, so many PN so little time but there
are some thoughts that it may be similar to the Soccerball PN Kronenberger 61 (http://www.gemini.edu/node/11656). T
he distance to K 1-14 would appear to be of the order of 5780 pc from GAIA DR2 or 4870 from the H-Alpha method.
The central star is however relatively faint at around 16.1 so the GAIA DR 2 parallax method may have some errors in it.

K 1-14 maybe a bit of a challenge to find and although there are drawings of it with a 27” by Uwe and Kent Wallace
saw it with his 20” it was described as faint. Jack Marling apparently had the first visual observation of it with a 17.5”
from altitude. Observations suggest an OIII filter is probably best to find this object. Perhaps not surprisingly this object
is not found in the NSOG Vol 2.

3549


As always give a go and let us know what you find.

Steve Gottlieb
June 6th, 2019, 05:35 PM
Nice challenge object, Owen. I observed this planetary back in 1986, also with my 17.5" (same site as Jack Marling) and an OIII (or UHC) was required to see the disc/ring.

I'm curious about the central star. The blue star with the tick marks on the Aladin image is much brighter than 16th magnitude -- close to mag 13.2. Kohoutek mentioned both interior stars in his discovery list, which he reported as m(B) = 13.7 and m(B) = 16.1. But you wouldn't think the fainter red star was the ionizing star.

obrazell
June 6th, 2019, 06:06 PM
Yes I too wondered about that. I am wondering if they go the wrong star. I tried to look for a GAIA mag but the conversion from GAIA mags to visual is non trivial, however SkySafari Pro which includes GAIA data converted suggests that star is around 13th mag. I am sure Wouter could give us the exact mag :-)

Owen

obrazell
June 6th, 2019, 06:15 PM
Ah Steve I just really zoomed in on this image and the bright star is s actually a double and the blue one is a much fainter part of that double pair so yes it may well be around 16th mag. GAIA does split the pair and gives the green mags as around 13.12 for the brighter one and 16 for the fainter one. The other star in the system at the 5 o'clock position is around 15.

Owen

wvreeven
June 6th, 2019, 06:44 PM
There, you solved the riddle yourself Owen. Nice!

Uwe Glahn
June 8th, 2019, 09:33 PM
Wow,

three stars within the PN, I didn't know that. With 293x I also could not separate the real CS but I think it could be a very tough challenge to do that when I saw the needed zoom level in PanSTARRS.

I just looked to my notes back in 2013. I wrote: [27", 293x, NELM 6m5+, Seeing III] thin, faint ring with different bright ring fragments with 293x; filling best visible with 244x and [OIII], filling brighter to the W; NBP filter brings out less detail
3552