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bus_ter

Andromeda is over rated!

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..... Ironically Edwin Hubble, the man who proved the remoteness of M31 in 1925, refused to call it the Adromeda Galaxy, as others started to do, and persisted with the rather lovely 'Andromeda Nebula' until his death......

Interesting stuff Olly :smiley:

I have a set of the 1928 cigarette cards called "The Romance of the Heavens". Card no. 15 shows what is termed a spiral nebula but admits that "their nature is not fully understood". Clearly the advisors to WD & HO Wills had not caught up with Hubbles results ! :smiley:

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You could say the same thing about the Milky Way - "completely invisible from my back garden, a barely visible patch of light from the edge of town, disappears completely in binoculars." Then go to a dark site and look at it. M31 has approximately the same surface brightness as the Milky Way so if you want to be anything other than disappointed you need to see it at a place where the Milky Way is visible to the naked eye. Then M31 itself will be easily naked-eye visible, binoculars will show the dust lane, an 8-inch will show star clouds within the galaxy itself, and a 12" will show its brightest globular clusters.

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I find the best way to see M31 is with my naked eyes. Bino's will show you some nice dust lanes though. I have trouble seeing a lot of detail in it with my f/7.9 scope. Lovely views we have of it though. Not over rated, just REALLY FAR AWAY!

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You could say the same thing about the Milky Way - "completely invisible from my back garden, a barely visible patch of light from the edge of town, disappears completely in binoculars." Then go to a dark site and look at it. M31 has approximately the same surface brightness as the Milky Way so if you want to be anything other than disappointed you need to see it at a place where the Milky Way is visible to the naked eye. Then M31 itself will be easily naked-eye visible, binoculars will show the dust lane, an 8-inch will show star clouds within the galaxy itself, and a 12" will show its brightest globular clusters.

What you say is completely true. However nobody ever explains that to people starting out in astronomy. So most people enter the hobby with expectations they feel are reasonable (being able to see the stuff that's shown in books, on the internet, etc.) However since all those images are just that: images, not eyeballed views, the feeling of disappointment when faced with reality is very common.
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What you say is completely true. However nobody ever explains that to people starting out in astronomy. So most people enter the hobby with expectations they feel are reasonable (being able to see the stuff that's shown in books, on the internet, etc.) However since all those images are just that: images, not eyeballed views, the feeling of disappointment when faced with reality is very common.

I remember seeing the orion nebula for the first time. I was like..."so am I looking at the wrong part? where's the colour? Oh... I see now, must be something wrong with my scope!" ...trundles to shop, buys new bigger scope, set-up, view.... "nope it's just a bit naff!"

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It's all just points of light isn't it?

Whether it's the Double Cluster, the Whirlpool Galaxy, the Ring Nebula, Albireo. Just spotty bits of light. Grease smudges on the EP.

And the Moon? just a lump of rock with holes on.

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OK controversial I know!

But all I see is a faint misty patch. I can't make out any detail, any shape, any colours.. well anything. I know it looks lovely when imaged, but through the EP I find it pretty boring. I would rather view a Planet, or a nice cluster or even a pretty double.

Am I doing something wrong? Do you need dark skies to see more than a foggy patch?

M31 is 3 degress wide. Even if you are using a 31 Nagler or 42LVW, they will only give you a tFOV of 1.1 or 1.3 deg in the C925. You were probably looking straight through most of it.

Edited by E621Keith
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Good point above. You do need a wide scope. This is where an F4 Newt steps up to be counted.

Olly

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What you say is completely true. However nobody ever explains that to people starting out in astronomy. So most people enter the hobby with expectations they feel are reasonable (being able to see the stuff that's shown in books, on the internet, etc.) However since all those images are just that: images, not eyeballed views, the feeling of disappointment when faced with reality is very common.

Completely agree and was surprised to see in the current Astronomy Now an article aimed at beginners with advice on what scopes are available at under £500 and what to see with them include a glorious colour picture of M42 with the caption "Visible even to the naked eye, the Orion Nebula makes a stunning telescopic object and is a favourite of observers, be they beginners or veterans". Included in the body of the article is this comment "Some nebulae and galaxies may look fainter than their colour-supplement depictions may indicate." All this in a popular astro mag. that I thought ought to know better.

Sorry to go a bit off topic but I feel this contributes to the disappoinment felt by some new comers.

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You definitely don't need a big scope to view M31, I disagree. In even a small scope you will have a nice image scale at an exit pupil of 5mm (its way bigger than the moon, so 16x in my little ST80 is already forming a good sized image). Your 20 inch F4 dob is not going to make the image brighter than my ST80 does, it will only make it bigger, which will reveal more detail of course, but the small scope is still going to show a lot of detail - under dark skies.

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The thing about M31 is that it doesn't show a lot of detail. In 10"+ of aperture you'll start to pick the two dust lanes closest to M110 out but inside those two arms what 'detail' is there?

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My point is you can also see that detail (the dust lanes, the fainter extended disk) with a pair of binoculars. 10 inch aperture will just show a bigger picture, one which may not fit in the eyepiece :-)

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The best view of M31 I've had is with my 20x80 Helios bins, it looked pretty expansive and bright, a nice gradient between the core and outer disc. Having said this the largest scope I've seen it through is a 6" Newt so it would be interesting to see it through a big Dob and see what the differences are?

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Best use a pair of bino's and a bigger newt for the best of both worlds then eh. :)

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You definitely don't need a big scope to view M31, I disagree. In even a small scope you will have a nice image scale at an exit pupil of 5mm (its way bigger than the moon, so 16x in my little ST80 is already forming a good sized image). Your 20 inch F4 dob is not going to make the image brighter than my ST80 does, it will only make it bigger, which will reveal more detail of course, but the small scope is still going to show a lot of detail - under dark skies.

A 20" dob will be about 40x brighter than a 80mm at the same magnification. However, a 20" f4 dob won't be able to frame the entire M31 either. Its tFOV will be limited to 1.3 degs with 2" eyepieces. Giant dob are not wide field instrument, you often see giant dobs using relatively large telescope as finder scope. Here is one extreme example http://www.obsessede...rg/msfinder.htm

A smaller dob will do well on widefield objects like M31. A 6" F5 Newt with a Nagler 31 and a ST80 with a Nagler 16 will both give you 3.3 deg field, but the Newt have a 6.3mm exit pupil and the ST80 a 3.2mm. The Newt's image will be 3.5 times brighter then the ST80, so aperture and size still matters

However, when it comes to galaxies, nothing can beat dark sky.

Edited by E621Keith

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OK controversial I know!But all I see is a faint misty patch. I can't make out any detail, any shape, any colours.. well anything.

This is why some of us prefer imaging. That 'faint misty patch' looks like this after a mere 600 seconds camera time.....

DSCF6344_1024.jpg

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It took me totally by surprise and being the nearest galaxy to Earth is the only chance you get to see that level of detail in another world. To see that sort of view at 2.5 million light years away makes it a very special object. You simply have to get to a star party, :)

Naughty Naughty....now that is a case of bad Astronomy in action...Now i know i am being pedantic, but M31 is not the nearest galaxy to Earth, it is simply the nearest major or spiral galaxy, or have you forgotten the LMC, SMC and the half dozen or so satellite dwarf Galaxies of the Milky Way...and the a Galaxy, regardless of size, is not another world...a planet is a world, not a galaxy..

OK..I'm off my soap box now...(I'll get me coat) :D

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For me dwarf galaxies and satellites galaxies aren't really galaxy, in the same way moons aren't planets. Mercury is smaller than Ganymede and Titan, but you don't ever consider the latter two planets. They orbit Jupiter and Saturn and as such they are part of Jupiter's and Saturn's system. I consider LMC, SMC and the dozen satellite dwarf galaxies part of Milky Way.

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By that reasoning only the largest galaxy in the universe is a galaxy - everything else is a dwarf!

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For me dwarf galaxies and satellites galaxies aren't really galaxy, in the same way moons aren't planets. Mercury is smaller than Ganymede and Titan, but you don't ever consider the latter two planets. They orbit Jupiter and Saturn and as such they are part of Jupiter's and Saturn's system. I consider LMC, SMC and the dozen satellite dwarf galaxies part of Milky Way.

That's ridiculous to be honest. The analogy between Moons and Planets does not hold water because there is (1) a historical difference (2) a scale difference (3) a reality difference.

Planets are so called because of the Greek Words for a "wandering Star", from memory it is asteres planetai and when researchers discovered that other planets had Lunaria (Moons) these were simply referred to as Moons...Scientifically they are satellite bodies that range in size from that of asteroids to that of full blown planets. It is sad that most people in society do not understand that many satellites in the solar system, and thus in the universe, are larger than many planets. One day we will likely find a Jupiter or larger sized planet with a "satellite" as large or larger than Earth, and to refer to such a large body in the same way as Phobos or Deimos is simply ludicrous.

Remember, planets are simply the dominant "Moons" of a star...however the majority of planets and the majority of planetary Moons formed where they live, less than a handful of bodies classed as Moons can be shown to have been captured by their parent body, and only one large Moon, Triton, falls into that category.

Galaxies are a wholly different animal, research seems to be indicating that all galaxies start as dwarves and grow to larger size by swallowing up those around them with some examples becoming dominant. There appears to be no evidence that a satellite galaxy forms in orbit about a larger galaxy, in the classical way that Moons form around planets. They form in the CDM halo that is believed to surround the dominant Galaxies, one exception is where an interaction with a co-orbital galaxy has stripped material from both the larger galaxies and there are a few examples of where this material has had time to begin to coalesce and will likely form a dwarf galaxy if they have time before the major galaxies coalesce themselves into a larger one that then swallows this material. I would refer you to "Dwarf Galaxies: Keys to Galaxy Formation and Evolution"

There is evidence that galaxy mergers are common, that Globular clusters may once have began to form as Dwarf Galaxies that where stripped of material by the parent galaxy, although this may not turn out to be the case, as evidenced in this research paper

Whichever way you look at it stating that Dwarf Galaxies are not Galaxies is akin to saying a Dwarf Human is not a Homo Sapien but a lesser species....

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Thanks for these interesting information. I didn't consider formation in my classification, because for me a satellite is a satellite. If LMC were free floating in intergalactic space like NGC3109, than I'd consider it a galaxy, but since it is in orbit of the much larger Milky Way, I will still think of it as part of Milky Way. I know this way of thinking gets complicated when you consider merger between galaxies like M81 and M82, but I am comfortable thinking M81 and M82 as a double system (for now). Both have super massive black holes while dwarf galaxies generally don't.

Personally I have some reservation to the current theory of globular cluster formation, this seems to be an area of active research. I will wait until the professionals agree with each other how glob formed. I wouldn't be surprise they will eventually come to a conclusion that some globular clusters are globular clusters while others are globular cluster like objects formed from the core of dwarf galaxy.

As for the debate whether Homo floresiensis is Homo sapiens or a separate species is way beyond me. I will accept what ever the biologist say.

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When it is situated high enough, I enjoy looking at M31 with averted vision at home, and direct vision from a dark site, binoculars and my scopes. In each case, it seems to offer something magical.

However my favourite view, which concur's with a previous post, is through my 12" f4.9 dob at a dark location with a 35mm panoptic (x43), this really does capture the light emitted from the expansive dust lanes and framed with M110 and M32 is a magnificent site.

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When it is situated high enough, I enjoy looking at M31 with averted vision at home, and direct vision from a dark site, binoculars and my scopes. In each case, it seems to offer something magical.

Agree with this. Simply magical from a dark site.

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