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M81 with ununaided eye

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#1 NDR

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Posted 12 March 2007 - 09:33 AM

I have a new observing spot. Last night was my second time there in three days. On the light pollution scale it says its in the yellow. But its in a big open feild in the country. There are a few farm houses off in the distance, with a light or two. Anyway I looked up where M81 and M82 are and I could just make out a faint smudge with my eye. I could not believe what I was seeing. I was seeing M81 with my unaided eye. Anyway I thought that was cool.

#2 jonathan89

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Posted 12 March 2007 - 12:00 PM

Very nice :D I wouldn't even dream about seeing that without my scope... the light pollution is BAD here...

#3 jonnyastro

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Posted 12 March 2007 - 12:08 PM

What magnitude is that galaxy?

#4 Phillip Creed

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Posted 12 March 2007 - 12:33 PM

What magnitude is that galaxy?


It depends on the source. Steven O'Meara's book on the Messier Objects has a brief discussion concerning the integrated magnitude of M81. If I recall correctly, O'Meara and Brian Skiff peg it at 6.8.

I've seen M81 with the naked-eye before, and it does require a pretty dark sky. I use a set of overcorrected glasses for stargazing, and this helps substantially. Generally speaking, I need to see stars down to magnitude 7.1 or 7.2 to see M81 without optical aid. This largely limits this endeavour to skies that are in the "blue" or better on the Clear Sky Clock LP map.

Clear Skies,
Phil

#5 palsing

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Posted 12 March 2007 - 01:59 PM

I have a new observing spot... on the light pollution scale it says its in the yellow... I looked up where M81 and M82 are and I could just make out a faint smudge with my eye. I could not believe what I was seeing...


I can't quite believe it, either, and think you might be mistaken. :D

Read Brian Skiff's account of his successful naked-eye observation of M-82, see

http://www.maa.aglei...pp/m81naked.txt

Basically, he says that to have any hope of seeing M-81 you must be able to identify, with certainty, several of the field stars in the immediate area, because any of them could certainly fool you into thinking you are seeing the galaxy itself. Brian is a very experienced observer, and his naked-eye observation of M-81 was only the 4th one ever documented, and his conditions were nearly perfect.

Brian concludes his report by saying; "Having tried this observation seriously (and unsuccessfuly) twice before, I found the key this time was getting all the field stars sorted out. Because there are several stars of similar brightness nearby, you really must be able to identify each of these in order to securely locate the galaxy."

So, give it another try, but this time make sure you can identify everything else in the area that might otherwise cause confusion.

I have personally tried to see this guy for over 40 years now, under near perfect conditions many times, and having a large-scale map of the immediate area, but have never been successful, my eyes just aren't good enough. Of course, through the 25", well, I'm always successful... ;)

#6 lunartic65

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Posted 12 March 2007 - 02:05 PM

I have read of M81 being spotted with the naked eye, but that was from altitude on the side of a dormant volcano in Hawaii, and I have to agree with my namesake that you might have been mistaken.

Paul

#7 NDR

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Posted 12 March 2007 - 02:37 PM

I have a new observing spot... on the light pollution scale it says its in the yellow... I looked up where M81 and M82 are and I could just make out a faint smudge with my eye. I could not believe what I was seeing...


I can't quite believe it, either, and think you might be mistaken. :D

Read Brian Skiff's account of his successful naked-eye observation of M-82, see

http://www.maa.aglei...pp/m81naked.txt

Basically, he says that to have any hope of seeing M-81 you must be able to identify, with certainty, several of the field stars in the immediate area, because any of them could certainly fool you into thinking you are seeing the galaxy itself. Brian is a very experienced observer, and his naked-eye observation of M-81 was only the 4th one ever documented, and his conditions were nearly perfect.

Brian concludes his report by saying; "Having tried this observation seriously (and unsuccessfuly) twice before, I found the key this time was getting all the field stars sorted out. Because there are several stars of similar brightness nearby, you really must be able to identify each of these in order to securely locate the galaxy."

So, give it another try, but this time make sure you can identify everything else in the area that might otherwise cause confusion.

I have personally tried to see this guy for over 40 years now, under near perfect conditions many times, and having a large-scale map of the immediate area, but have never been successful, my eyes just aren't good enough. Of course, through the 25", well, I'm always successful... ;)


I am not mistaken. I have very good vision 20/10 thats twice 20/20.

#8 Phillip Creed

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Posted 12 March 2007 - 03:59 PM

Observers have reported naked-eye sightings of objects fainter than M81. I saw a report from David Knisely about a naked-eye sighting of M27 (!) from the Nebraska Star Party. Some observers have reported sightings of NGC 253 from the Southern Hemisphere.

I found that the key is the 7.1-mag star a little more than a degree east of M81. If I can't detect that star, I don't even bother with the attempt at M81.

Since Joshua Roth's September 2005 S&T article on nighttime myopia, a lot of observers (myself included) have employed overcorrected lenses for stargazing. The improvement in NLM is substantial, and I expect many more naked-eye sightings of M81.

Last Saturday night, I was at a site that's in the "yellow" on the CSC LP map, but the sky was amazingly transparent. You could still tell it wasn't exactly Spruce Knob, but the transparency in combination with my overcorrected specs allowed the NLM to go a little deeper than I suspected. I was just able to see a 6.6-mag star in the Bowl of the Big Dipper.

Clear Skies,
Phil

#9 Dave M

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Posted 12 March 2007 - 04:14 PM

Phil,

I recall you seeing M81 from Calhoun when we was there
back on Nov/24 06...Same night we seen gegenschein and the
zodiacal band.
Not sure if you included the M81 NEye observation in the observing report you wrote though.

#10 Phillip Creed

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Posted 12 March 2007 - 07:24 PM

Dave,

I just took a peek back at that observing report. It's in there, toward the bottom of the OR.

Clear Skies,
Phil

#11 Doug Brown

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Posted 14 March 2007 - 07:59 AM

I do most of my viewing from a yellow zone, but on good nights, and if the object is in the “sweet spot” you can really surprise your self and see things you might think you needed much darker skis to view.

#12 Jim Rosenstock

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Posted 14 March 2007 - 09:51 AM

I've seen M81 with the naked-eye before, and it does require a pretty dark sky. I use a set of overcorrected glasses for stargazing, and this helps substantially.


Ummmm, then that's NOT naked eye, is it??

I've "seen" LOTS of objects with "averted imagination" :lol: but frankly I don't find these M81 reports credible. But if you guys want the bragging rights, by all means, brag away.

One thing's for sure: M81 looks a LOT more interesting viewed through a telescope or binoculars.

Jim

#13 Steph

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Posted 14 March 2007 - 12:35 PM

Now now, just because one person may not be able to do something, doesn't mean others can't. Let's be careful how we phrase our posts when expressing doubt about something like that, because we wouldn't want to seem as if we're calling someone else a liar since that wouldn't be nice...and would also be against CN's TOS. (Please note this is a general comment to all and not directed to anyone in particular at the moment.)

I'd have to agree with Jim's last statement, though, and I'd guess most folks would too... :)

#14 Phillip Creed

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Posted 14 March 2007 - 12:37 PM

Jim,

First of all, everyone's eyes are different. Some of things that Steve O'Meara can see, dark sky or not, are simply astounding (M81 naked eye? Try the Helix Nebula!!!). Age also plays a factor.

Second, you do have a point about the overcorrected glasses. Technically, my God-given naked-eye limiting magnitude is about 3.5 since every star looks like it's 30' across. I guess you could say I'm a leeeeeeetle near-sighted.

I asked Dan Green about this when making a comet observation. I asked him if there was a special instrument code for using eyeglasses vs. a true naked-eye observation, and he responding with something like, "naked-eye is naked-eye".

Here's a list of deep-sky objects that are considered "naked-eye" under perfectly dark skies:

http://www.visualdee...t/msg01732.html

Some of these are a bit more astounding than M81.

There's another ongoing CN thread concerning naked-eye faint fuzzies:

http://www.cloudynig...5/o/o/fpart/all

Clear Skies,
Phil

#15 Rick Woods

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Posted 14 March 2007 - 02:17 PM

I have a new observing spot. Last night was my second time there in three days. On the light pollution scale it says its in the yellow. But its in a big open feild in the country. There are a few farm houses off in the distance, with a light or two. Anyway I looked up where M81 and M82 are and I could just make out a faint smudge with my eye. I could not believe what I was seeing. I was seeing M81 with my unaided eye. Anyway I thought that was cool.

NDR,
That's very impressive. I wish my eyes were half that good.
Congratulations!
- Rick

#16 Ptarmigan

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Posted 14 March 2007 - 04:55 PM

That's really hardcore! :bow: M81 is probably the farthest and faintest object to see with your own eyes without any optical aide. Most consider M31 and M33 the farthest. That's really cool. :cool: :bow:

#17 Amalia

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Posted 16 March 2007 - 03:48 PM

I have a new observing spot... on the light pollution scale it says its in the yellow... I looked up where M81 and M82 are and I could just make out a faint smudge with my eye. I could not believe what I was seeing...


I can't quite believe it, either, and think you might be mistaken. :D

Read Brian Skiff's account of his successful naked-eye observation of M-82, see

http://www.maa.aglei...pp/m81naked.txt

Basically, he says that to have any hope of seeing M-81 you must be able to identify, with certainty, several of the field stars in the immediate area, because any of them could certainly fool you into thinking you are seeing the galaxy itself. Brian is a very experienced observer, and his naked-eye observation of M-81 was only the 4th one ever documented, and his conditions were nearly perfect.

Brian concludes his report by saying; "Having tried this observation seriously (and unsuccessfuly) twice before, I found the key this time was getting all the field stars sorted out. Because there are several stars of similar brightness nearby, you really must be able to identify each of these in order to securely locate the galaxy."

So, give it another try, but this time make sure you can identify everything else in the area that might otherwise cause confusion.

I have personally tried to see this guy for over 40 years now, under near perfect conditions many times, and having a large-scale map of the immediate area, but have never been successful, my eyes just aren't good enough. Of course, through the 25", well, I'm always successful... ;)


I am not mistaken. I have very good vision 20/10 thats twice 20/20.



Personally I don't think this to be exaggerated, or a mistake.
After all, as you can read in my signature line, I have
been able to spot 26.5 Alpine Marmots (marmota marmota) in
ten minutes. Believe me, seeing M 81 with bared eye seems
an easy run compared to all these wildly running marmots! :ubetcha:

Best,

Amalia

#18 conus

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Posted 17 March 2007 - 11:17 AM

.5 of a Marmot?

#19 LivingNDixie

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Posted 17 March 2007 - 03:53 PM

What is a marmot?

#20 Steph

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Posted 17 March 2007 - 03:57 PM

Not a deep sky object, I'm pretty sure...

#21 Amalia

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Posted 19 March 2007 - 03:35 PM

What is a marmot?



Not a deep sky object, I'm pretty sure...



:tonofbricks: Don't tell me that you *really* don't know
what a marmot is... :shocked:

Alpine marmots are quite common in our Swiss mountains,
however it is rather seldom to be able to spot more than
maybe ten of them.

Here a Wikipedia explanation:
http://en.wikipedia....i/Alpine_Marmot


.5 of a Marmot?


A joke, of course -- allow me to quote myself:

I was very influenced by Kenny J, our Binocular Sheep Counting Champion... ;)

But I truly have observed that much alpine marmots in
this short time. It was last summer, and as there were
amazingly many marmots, so "the jury" was not able to
correctly follow my fast discoverings.

Well, we have to imagine alpine marmots as very lively
beings, often moving, even if in the late summer they
carry a quite considerable belly. So it happened that
nobody, "nor the jury, nor me", was sure if "we" had counted
a specific marmot. And so "we" agreed in a compromise which
said that this marmot shall be counted as half a marmot.

All clear? ;)


Amalia

#22 Telescoper

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Posted 20 March 2007 - 03:07 PM

I asked Dan Green about this when making a comet observation. I asked him if there was a special instrument code for using eyeglasses vs. a true naked-eye observation, and he responding with something like, "naked-eye is naked-eye".



Not sure about that. Naked-eye to me has always meant observing at zero power, like with glasses corrected to 20/20 or thru a Telrad. If not, then I haven't seen anything naked-eye for years. If his "overcorrected" glasses are giving him some 2x or 3x power magnification advantage, then that's not naked-eye on M81.

#23 Phillip Creed

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Posted 21 March 2007 - 12:16 PM

I asked Dan Green about this when making a comet observation. I asked him if there was a special instrument code for using eyeglasses vs. a true naked-eye observation, and he responding with something like, "naked-eye is naked-eye".



Not sure about that. Naked-eye to me has always meant observing at zero power, like with glasses corrected to 20/20 or thru a Telrad. If not, then I haven't seen anything naked-eye for years. If his "overcorrected" glasses are giving him some 2x or 3x power magnification advantage, then that's not naked-eye on M81.


To clarify, it's not his eyeglasses. It refers to a set of special eyeglasses I had made that correct for the phenomenon of nighttime myopia. They're 3/4-diopter overcorrected for my already myopic eyes. They don't give me any magnification whatsoever, but they do make individual stars PINPOINT sharp at night.

I asked Dr. Green the question because it concerned a comet brighter than 6th magnitude. If the comet's coma is very condensed and small, an in-focus estimate of a comet's brightness can be made.

If the comet is bright but has a 15' coma, it's becomes more difficult to estimate the integrated brightness of the comet. In a situation like that, I'd remove my glasses and defocus the stars until I have a set of "comparison comets", and make a mag estimate accordingly.

My question to him was whether or not I needed a separate instrument code for each of the afore-mentioned scenarios, and he said no.

Clear Skies,
Phil


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