So...can you see the Sombrero Galaxy with an 8" Dob? Is it like trying to spot Neptune...?
The short answer is, Yes,
It requires a darkish sky and moderate to high mag for an 8".
Get yourself a good star chart and star hop away to your hearts content,once you have found it you will wonder how you missed it all this time.
Cheers
It's easier to spot than Neptune, because at moderate powers Neptune
looks like a slightly enlarged colour tinted star, whereas The Sombrero
looks quite different to everything around it, so is much more obvious.
Good hunting.
raymo
I can spot the Sombrero in my 11X70 binos from my home in Sydney. An 8" dob is not a problem & I've also seen it through an 8" dob from home.. BUT, it is not a large object, so can be difficult to identify. As Ron says, a good chart is a must, be it paper or digital. At low magnification it appears as a short, thin streak of faint nebulous light. Highrr magnification will reveal its more recognizable features.
Take your time. It is a devil of a target to nail, just challenging.
Here in Colac M104 is an easy get in 11x70 and have nabbed it with 10x50s. Never quite managed it with a finder though t should be visible in one.
Star hopping to it is very easy as described. The dark lane was usually only discernable in my 12" in good conditions, but if conditions were such that the lane could be seen, the galaxy as a whole handles high power nicely as there is plenty of contrast.
So you are aware that it is not an impossible target, I've also spotted M104 in a humble little 6X30 finder from a dark site. That night I also spotted M83 and Centaurus A with that same little finder.
Starry Night says it has an apparent magnitude of 9.5, do it should definitely be visible through an 8" dob. I even want to give it a go with my 5" dob one of these days...
Starry Night says it has an apparent magnitude of 9.5, do it should definitely be visible through an 8" dob. I even want to give it a go with my 5" dob one of these days...
A little note of caution about "apparent magnitude". It is very different from 'visual magnitude'.
This refers to the entire light from the combined surface area of extended objects, not the actual visual magnitude that a point source is, like a star. So for a given apparent magnitude, the larger the object, the fainter the actual image will be as the apparent magnitude is spread out over a large area.
The apparent magnitude of the LMC is nearly as bright as Sirius. But the brightness that we actually see it at is no where near as bright as Sirius. Like wise with ALL extended objects.
This can mean that some objects are very, very, very difficult to actually see. Two such examples are the galaxy M33 and the Rosette Nebula, NGC 2244. Both are very big objects, M33 the size of the full Moon, the Rosette three times the Moon's diameter. M33's apparent magnitude is 5, the Rosette's 9. While both are relatively bright, through a scope they are extremely faint due to their large size spreading out their light so much.
"Apparent magnitude" is a loaded gun for the unwary. You need to take into account the size of the object, and not confuse it with 'visual magnitude'.
Likewise, the Sombrero will not appear as a magnitude 9, 9.5 object. It will actually appear dimmer, which is why it is hard to pin down.
Starry Night says it has an apparent magnitude of 9.5, do it should definitely be visible through an 8" dob. I even want to give it a go with my 5" dob one of these days...
It's no problem in my 120mm F5 refractor. But yeah as Alex says the magnitudes of DSO's can be deceptive. That goes for comets too.
I have found it with my 8inch dob. The rule "of 3 groups" is what I made up to find. First first find constellation Corvus and it`s star Algorab (use Stellarium for example to find it) and η Corvi - you can say these 2 stars are close and form a pair, our first "group". Then "up" from corvus there are some stars very close to each other, than find the thr third group like at the image. Center on the third group and switch from finderscope to telescope. These stars form an "arrow", connect it's stars with an imaginary line and you'll find the galaxy. Illustrated: http://i.imgur.com/Hn2aNCf.jpg
This thread prompted me to have a go at finding it last night.
Transparency, 3/5, cloudy day, night was 'clear' but seemed a little fuzzy up high, ice maybe.
Seeing similar 3/5 only zenith seemed reasonably stable.
I was out from about 2030 till 2130 on the driveway with the 10" f5 Newt in it's DOB cradle
Temp cool, humidity low for Auckland. Almost zero wind.
M104 was close to Mars last night, a good starting point.
Hunted for over half an hour in the right region with no luck at all so gave up and went over for a quick look at Eta C and Crux.
Swung back to have another look just after 9 pm. Found Algorab, slid down (North) to the long arrow asterism with it's three star triangle 'head'. Followed that direction a little more to the three star lineup Kevin shows and bingo it popped into view. It sits in a small asterism I call 'The Shopping Trundler' for obvious reasons when you see it.
Small but distinctive glow in the 20mm SV, the 15mm dimmed it but also revealed the dark edge. I managed to use both the TMB 9mm and 6mm Planetarys and still see it albeit quite dim. 9mm gave the best edge definition, a compromse between dimness and size.
This is still in my Nth sky over the CBD so a fair amount of LP up there.
I suspect I might be able to see it just with the 102mm F7 Lunt but photographically it would be too small. This weekend is not predicted to have good weather but I'll remount the Newt onto the EQ6 and the DSLR and hope for a chance to improve on my last imaging effort for this target.
I wanted to give it a go too last night... But it was behind a huge leafy tree... I know for sure by looking at the position of Mars, which was just under the tree.
Last edited by OzStarGazer; 21-05-2014 at 04:19 PM.
Had a crack last night with the little 8". Really clear night and M104 was lovely. Bright and extended with the dark lane very clear. Was only at 53x with a 15mm 68deg EP which had the 3 stars in a line at the edge of the field.
Got to say, after whats been said M104 seems hardly worth the effort other than a navigational exercise. i'll have a crack tonight & see if it's worth it or not.
I know for sure by looking at the position of Mars, which was just under the tree.
