Paul Alsing
August 24th, 2020, 04:31 AM
Object of the Week, August 23rd, 2020 - NGC 6751, PN G029.2-05.9, PK 029-5.1, ARO 101 in Aquila
R.A.: 19h05m55.6s Dec.: -05°59'33" (2000)
Size: 20"
Magnitude: 12.00 Surface brightness 18.2 Mag/arcsec²
The beautiful planetary nebula NGC 6751 is also known as the Glowing Eye Nebula, and less often as the Dandelion Puffball Nebula. It was discovered in 1863 by Albert Marth, but he apparently mis-recorded its location by a couple of arcminutes, it was discovered again by Edouard Stephan in 1871 and subsequently list as NGC 6748, and finally rediscovered by Stephan again in 1881 and eventually listed as NGC 6751.. so, NGC 6748 = NGC 6751! Steve Gottlieb's great NGC observing notes expand the details of this story, and you can find those here...
https://tinyurl.com/y4o4ou7j
The diameter of this nebula is about 0.85 light-years, or about 600 times the size of our solar system. NGC 6751 is about 6500 light-years from us in Aquila, although different sources quote varying distances. It is located about 30” southeast of the wonderful red carbon star V Aql and about 20” northwest of the dark nebula Barnard 134.
NGC 6751 gained a lot of notoriety when this image of NGC 6751 was selected in April 2000 to commemorate the tenth anniversary of Hubble in orbit. The colors were chosen to represent the relative temperatures of gas (blue, orange and red, the hottest gas to the coldest)…
3982
Of course, it did not quite look like this when I last laid eyes on this little guy. At my lowest power this fellow is tiny, and looks like somewhat bloated and bluish star. Increasing power to about 400x show it to be a smaller version of the Ring Nebula, with a brighter annulus and a darker middle, with an obvious central star smack in the middle. Very nice, and available even to smaller telescopes.
For those of you with a lot of glass, there is a hotspot in the halo of NGC 6751 that may not have ever been observed. Planetary nebula observer extraordinaire Kent Wallace posted about HuLo 1 way back in 2002 on Amastro so you might consider going to amastro and reading the whole thread about HuLo 1, which is here…
https://groups.io/g/amastro/search?q=Hulo+1
... but you may need to join the group to see it, if you are not already a member. Although not very active recently, amastro was a treasure trove, for me, for finding out about obscure objects to observe for many years, and I culled a LOT of really good information during its heyday. Another fine observer, Kent Blackwell, said this about his attempted observation of HuLo 1, using his 25” f/5 dob… “Try as I might I just can't say for sure whether I saw it. I did suspect a "spray" of ef nebulosity but just can't be sure without a good image to go by”. Here is a fabulous much wider-field picture of NGC 6751…
3985
... and it seems to me that the large nebula to the upper-left of the planetary is the elusive HuLo 1… of course, it might be just another “ain’t no way you’re going to see this” worthy of the late Barbara Wilson’s famous list, the aintno 100...
https://www.astronomy-mall.com/Adventures.In.Deep.Space/aintno.htm
As always, give it a go and let us know.
R.A.: 19h05m55.6s Dec.: -05°59'33" (2000)
Size: 20"
Magnitude: 12.00 Surface brightness 18.2 Mag/arcsec²
The beautiful planetary nebula NGC 6751 is also known as the Glowing Eye Nebula, and less often as the Dandelion Puffball Nebula. It was discovered in 1863 by Albert Marth, but he apparently mis-recorded its location by a couple of arcminutes, it was discovered again by Edouard Stephan in 1871 and subsequently list as NGC 6748, and finally rediscovered by Stephan again in 1881 and eventually listed as NGC 6751.. so, NGC 6748 = NGC 6751! Steve Gottlieb's great NGC observing notes expand the details of this story, and you can find those here...
https://tinyurl.com/y4o4ou7j
The diameter of this nebula is about 0.85 light-years, or about 600 times the size of our solar system. NGC 6751 is about 6500 light-years from us in Aquila, although different sources quote varying distances. It is located about 30” southeast of the wonderful red carbon star V Aql and about 20” northwest of the dark nebula Barnard 134.
NGC 6751 gained a lot of notoriety when this image of NGC 6751 was selected in April 2000 to commemorate the tenth anniversary of Hubble in orbit. The colors were chosen to represent the relative temperatures of gas (blue, orange and red, the hottest gas to the coldest)…
3982
Of course, it did not quite look like this when I last laid eyes on this little guy. At my lowest power this fellow is tiny, and looks like somewhat bloated and bluish star. Increasing power to about 400x show it to be a smaller version of the Ring Nebula, with a brighter annulus and a darker middle, with an obvious central star smack in the middle. Very nice, and available even to smaller telescopes.
For those of you with a lot of glass, there is a hotspot in the halo of NGC 6751 that may not have ever been observed. Planetary nebula observer extraordinaire Kent Wallace posted about HuLo 1 way back in 2002 on Amastro so you might consider going to amastro and reading the whole thread about HuLo 1, which is here…
https://groups.io/g/amastro/search?q=Hulo+1
... but you may need to join the group to see it, if you are not already a member. Although not very active recently, amastro was a treasure trove, for me, for finding out about obscure objects to observe for many years, and I culled a LOT of really good information during its heyday. Another fine observer, Kent Blackwell, said this about his attempted observation of HuLo 1, using his 25” f/5 dob… “Try as I might I just can't say for sure whether I saw it. I did suspect a "spray" of ef nebulosity but just can't be sure without a good image to go by”. Here is a fabulous much wider-field picture of NGC 6751…
3985
... and it seems to me that the large nebula to the upper-left of the planetary is the elusive HuLo 1… of course, it might be just another “ain’t no way you’re going to see this” worthy of the late Barbara Wilson’s famous list, the aintno 100...
https://www.astronomy-mall.com/Adventures.In.Deep.Space/aintno.htm
As always, give it a go and let us know.