TheSkySearchers

When observing M31 I have never seen M32. Right click the image.

It would be tricky for me with my tired old eyes! Stellarium reports a surface brightness of 12.17. I would have thought you should be able to see M32 as a slightly fuzzy star once you have those surrounding brighter stars recognised.

Regards

Graeme

Seeing M32 is a matter of expectations. From looking at photos, we expect to see M32 as a bright mini-galaxy sitting on the rim of M31's disk.
However, looking through an eyepiece, you will see a slightly fuzzy star a surprisingly long distance from M31's core. This is a photograph, of course, but I deliberately processed it to resemble what I could see with a low-powered eyepiece under Bortle 2-3 skies.

I have recently had a nice view of M32 at 160X with an 8 inch SCT. I used a goto mount to locate easily and drilled in with successive EP which isolates the view and reveals M32 pretty well. The sky was bortle 3.5-4 and the pupil of the sky through which I was viewing was well suited.

In wide field views M32 has often been illusive unless I have very good transparency. Kathryn's representative image is an excellent illustration of my usual wide field view. I probably viewed M31 a half dozen times before I understood the relative positions and identified M32 in visual observation.

Actually, I suspect you likely have seen M32, but simply did not know it because you lack perspective of what you should see. There is a big difference between M32 and M110 visually, the two main satellite galaxies of M31. While their visual magnitudes are the same (8.1), their surface brightness is quite different (12.4 and 14.0 respectively). As depicted in the images, M32 is positioned closer to the galactic disk of M31 to its southeast. M110 is even farther removed from M31 but to its northwest, more or less opposite of M32. The second example provided by Kathy is fairly typical of the visual presentation when viewed from areas with noticeable light pollution.

From my typical suburban back yard, M32 is always visible, even on the worst nights, while M110 might be invisible during nights of particularly poor transparency. I liken M32 to a small unresolved globular cluster in appearance. From our dark site, the experience is a little different however. The outer structure of M31 extends much farther out because of the lack of LP, and M32 is often just involved at the outer fringes of M31 and this causes it to actually appear dimmer than M110 because it is engulfed within the brightness of M31's galactic disk. But that is not the normal view that most will see from the typical backyard.

The main thing to remember is to look for the star patterns as depicted in your Stellarium screen capture and triangulate M32 using them. M32 will not appear stellar, rather as a diffuse fuzzy star or as I said a small globular cluster that will not resolve. See my annotated version of your image below. As a bonus I also indicated the brightest star cloud in M31, NGC 206, so be sure to look for that as well. FYI, no need to right click the images, a single left click will do the job - at least it does for me.

Good luck, and rest assured you should definitely see it, and in all likelihood, have done so unbeknownst to you.

My experience using an ST120 matches Kathy's overprocessed pic - a fuzzy star at a surprising distance away from the core of M31. It took me awhile to determine if I was looking at M32 or M110, but that I got that sorted out by studying my SS screen and paper atlas. The downside is I haven't spotted M110 yet.

Thanks to you all for your advice. I just returned from my bortle 4 dark site. However, I could not park at the rear of the property. The ground was damp at the rear. I could drive on it, but did not want to park. I skidded a few times. So my thinking was as time passed, the weight of the car would take me deeper into the ground. The front of the property has a parking lot and entrance light at the small building door. It was still dark enough for direct sight of Andromeda, but no night vision adaptation from the front. I tried spotting M32 within Andromeda at the 10, 11, and 12 o'clock positions, but no luck. I used my 40mm plossl for a wider exit pupil, but no luck. Andromeda was a little more then 2 degrees wide. I have seen it wider and brighter at Maryland's Point Lookout State park, which is a 10 minutes drive away. It could have been the atmosphere, because Mars showed less detail than I cold see under my home bartle 9 skies. Still had a good time.

Refractordude wrote: ↑Thu Oct 15, 2020 6:00 am I tried spotting M32 within Andromeda at the 10, 11, and 12 o'clock positions, but no luck. I used my 40mm plossl for a wider exit pupil, but no luck. Andromeda was a little more then 2 degrees wide. I have seen it wider and brighter at Maryland's Point Lookout State park, which is a 10 minutes drive away. It could have been the atmosphere, because Mars showed less detail than I cold see under my home bartle 9 skies. Still had a good time.

As Kathy mentioned above, you are probably looking too close to the core of M31. I was not sure many times as well until I viewed a drawing of M31 and M32. Visually, it almost appears as far from the core as M110 does on the other side. Once you realize it's not "in" the nebulosity of M31 like it appears in most photos, she is very easy to spot.


Drawing courtesy of Kenneth Glyn Jones' book Messier's Nebulae & Star Clusters.

For me, the M32 makes a skewed parallelogram with three unrelated stars in the foreground of M31.

Easily seen as small disc through the binoculars as small as 10.5x70 under Bortle 4. Documented with more than 100 observing notes.

Clear skies,
JG

Refractordude wrote: ↑Thu Oct 15, 2020 6:00 am ... I tried spotting M32 within Andromeda at the 10, 11, and 12 o'clock positions, but no luck. I used my 40mm plossl for a wider exit pupil, but no luck. Andromeda was a little more then 2 degrees wide. I have seen it wider and brighter at Maryland's Point Lookout State park, which is a 10 minutes drive away. It could have been the atmosphere, because Mars showed less detail than I cold see under my home bartle 9 skies. Still had a good time.

I think you are right about the atmospheric conditions at the seashore. I tried observing from the Outer Banks under what looked like pretty clear skies but resolution was pretty terrible each time.

Nice! Now, due to Kathy's pictures, I can probably spot them too - when it comes dark enough again.

M32 has a higher surface brightness than M31. Even here in Los Angeles, when all that is visible of M31 is the core, M32 stands out.
This may surprise you, but it is probably among the 5 brightest galaxies in the whole sky. It is visible in skies where M81/82 and M104 are invisible.
It's all about expectations--it is a small spherical galaxy, and that is probably why it was difficult to find or see.
It is bright enough I can view it at 500x, a magnification where most other galaxies have been dimmed to invisibility.

Once you find it, and identify it, you will never have any problem seeing it again.

Interesting. I tried to observe M81 last week but it wasn't visible here in suburban Maryland.

I don't really understand why Surface Brightness might be more important than apparent magnitude.

GCoyote wrote: ↑Fri Jun 11, 2021 11:55 pm Interesting. I tried to observe M81 last week but it wasn't visible here in suburban Maryland.

I don't really understand why Surface Brightness might be more important than apparent magnitude.

The apparent magnitude is what the magnitude would be, if all the light from the surface was coming from a point.
Or, surface magnitude is (roughly) apparent magnitude (or rather, the flux) spread all over the surface (evenly).
Neither of them gives a very good indication of how bright it would appear to you, because neither takes into account the
"spread function" of the light. Looking at both AND the apparent size of the object gives you some kind of idea.

turboscrew wrote: ↑Sat Jun 12, 2021 10:16 am

GCoyote wrote: ↑Fri Jun 11, 2021 11:55 pm Interesting. I tried to observe M81 last week but it wasn't visible here in suburban Maryland.

I don't really understand why Surface Brightness might be more important than apparent magnitude.

The apparent magnitude is what the magnitude would be, if all the light from the surface was coming from a point.
Or, surface magnitude is (roughly) apparent magnitude (or rather, the flux) spread all over the surface (evenly).
Neither of them gives a very good indication of how bright it would appear to you, because neither takes into account the
"spread function" of the light. Looking at both AND the apparent size of the object gives you some kind of idea.

Thanks. That does make sense. I'll try to compare a few objects on my next clear night and see if I can get a better feel for the difference.

Clear skies!

Note, however, that (visual) magnitude is not linear scale, but (if I recall it right) about 2.7 exponential function.
That is: a star of magnitude 3 is about 2.7 times brighter (in terms of flux) than a magnitude 4 star.

Understand, whereas the surface brightness is just the flux averaged over the apparent surface?

GCoyote wrote: ↑Sat Jun 12, 2021 12:40 pm Understand, whereas the surface brightness is just the flux averaged over the apparent surface?

Yes. My understanding is that the 2.7 comes from the dynamics of the human eye. Most human senses go with about 2.5 exponent, but for eye the base is 2.7. That is: if the flux of B is 2.7 x flux of A, and flux of C is 2.7 x flux of B (= 2.7 x 2.7 x flux of A), the brightness difference between A and B looks as big as the brightness difference between B and C.

turboscrew wrote: ↑Sat Jun 12, 2021 12:48 pm

GCoyote wrote: ↑Sat Jun 12, 2021 12:40 pm Understand, whereas the surface brightness is just the flux averaged over the apparent surface?

Yes. My understanding is that the 2.7 comes from the dynamics of the human eye. Most human senses go with about 2.5 exponent, but for eye the base is 2.7.

In other words it follows a natural logarithmic scale.

GCoyote wrote: ↑Sat Jun 12, 2021 12:51 pm

turboscrew wrote: ↑Sat Jun 12, 2021 12:48 pm

GCoyote wrote: ↑Sat Jun 12, 2021 12:40 pm Understand, whereas the surface brightness is just the flux averaged over the apparent surface?

Yes. My understanding is that the 2.7 comes from the dynamics of the human eye. Most human senses go with about 2.5 exponent, but for eye the base is 2.7.

In other words it follows a natural logarithmic scale.

Oops! Double checked! I remembered wrong. The base for visual magnitude is about 2.5! Not about 2.7.
(Actually the base is defined to be 5th root of 100.)

I guess I have to check a bunch of other stuff as well. My memory seems to have done a major sommersault here.