M57 central star

[Piero]

Last night I was out with my 16" f4 + PC2. Most of the time was spent on Cygnus and M56 in Lyra, although M57 near the zenith is difficult to ignore.

This planetary nebula looks beautiful in this telescope. This time I was not interested in its nebulosity, but in the white dwarf at its centre. This star is estimated between 15 and 15.2 mag, but the main difficulty is the presence of the gas surrounding the nebula. To decrease the apparent surface brightness of the nebula and increase the brightness of the star, high magnification is required. My Delos 6mm gives 311x. Although at this magnification a lot of dim stars become kind of more visible, after spending time observing it was clear that the gas of planetary nebula was still too bright. Therefore, I added my modded Baader VIP barlow (1.83x) and used first my Delos 8mm (427x) and then the Delos 6mm (570x). Using either these two eyepieces, I managed to detect a faint glimpse of the central star. It was not easy though. First of all, I needed to use an eye patch on my other eye to relax my observing eye. Secondly, my observing eye had to be dark adapted. This meant to continue observing the nebula for a few minutes constantly, wearing an observing hood. Although I spotted the central star in direct vision, I used to slowly rotate my eye around the nebula ring to help the eye rods. The central star is elusive. It was not visible all the time, but its visibility is heavily seeing-dependent. For instance, it was literally invisible, then it popped up for 1-2 second very faintly, and then it disappeared from my eye. I managed to see it three times last night: two times with the Delos 8 + VIP, 1 time with Delos 6 + VIP. 

It is also quite interesting to see how the M57 surrounding landscape gets populated by stars as the magnification increases.

Once indoors, I did some research and found this image compiled by Brian Skiff (Lowell Observatory) showing the nearby faint stars and their magnitude: 

 

 

Here is an amazing video about M57: 

https://youtu.be/6FSIfUYFeTM

Edited August 5, 2021 by Piero

[John]

Excellent report Piero

I (just about) managed something similar back in June.

 

 

 

[mdstuart]

Well done  I have tried but no luck even with my 4.7mm eyepiece. 

Will try at the October star party!

Mark

[faulksy]

well done piero. seen it when i first built my dob. had it confirmed by my wife as well. just incase it was averted imagination. seen it a few times since as well 👍

[jetstream]

Congrats!

Another milestone achieved Piero!

I see it in the 15" f4.8 easiest and most consistent using a vg sample of a KK 7mm ortho at 261x. Your right about seeing... if really high mag is needed everything becomes more seeing dependent IMHO. Dark adaptation is crucial as you say as are other things.

Cant wait to hear your sightings of those faint little lettered stars near the trapezium in M42!👍

[jetstream]

2 hours ago, mdstuart said:

Well done  I have tried but no luck even with my 4.7mm eyepiece. 

Will try at the October star party!

Mark

Mark, if I might ask which 4.7mm eyepiece your using for this?

[Piero]

55 minutes ago, jetstream said:

Congrats!

Another milestone achieved Piero!

I see it in the 15" f4.8 easiest and most consistent using a vg sample of a KK 7mm ortho at 261x. Your right about seeing... if really high mag is needed everything becomes more seeing dependent IMHO. Dark adaptation is crucial as you say as are other things.

Cant wait to hear your sightings of those faint little lettered stars near the trapezium in M42!👍

 

I think you can use lower mag due to the darkness of your skies. Under my skies, I am not sure there is enough contrast to temporarily spot it under 300x, but I might be wrong.

How does the nearby faint IC 1296 look like over there? (Apparent "nearby" - that barred spiral galaxy is 256Mly distant from us, compared to the 'just' 2Kly of M57). Although there seemed to be something small and fuzzy where that object is located, I would not bet on it as it could have just been a faint star rather than the core. 

[mdstuart]

1 hour ago, jetstream said:

Mark, if I might ask which 4.7mm eyepiece your using for this?

Explore scientific...82 deg

[jetstream]

4 hours ago, mdstuart said:

Explore scientific...82 deg

It might be worthwhile to barlow the 10 BCO for this Mark, our 6.7 ES 82, while a good eyepiece is down on transmission and up on scatter a bit.

[jetstream]

4 hours ago, Piero said:

How does the nearby faint IC 1296 look like over there?

Years ago I observed this object a fair bit but I kind of forget the nature of the observation. These days I visit the Ring for a quick visit and keep sky cruising. I'll revisit once the transparency is better here.