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Date: 24 Jul 2006 07:56:20
From: Dennis Woos
Subject: Observing Barnard's Galaxy (NGC6822)
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Anybody have any reports/tips on observing Barnard's Galaxy? Last night a
friend and I looked at the planetary nebula ngc6818, and thought it would be
easy to include this galaxy. Surprisingly, neither of us could find it in a
10" f/6 dob and 20x80 binos. I now read that this is a famous object, and
that it can be challenging to observe because of it's low surface
brightness. Maybe with what I have read this morning we could now locate
it, but we sure couldn't last night. I am definitely going to try again the
next chance I get.
Dennis
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Date: 24 Jul 2006 10:48:06
From: Willie R. Meghar
Subject: Re: Observing Barnard's Galaxy (NGC6822)
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"Dennis Woos" <dpwoos@gmavt.net > wrote:
>Anybody have any reports/tips on observing Barnard's Galaxy? Last night a
>friend and I looked at the planetary nebula ngc6818, and thought it would be
>easy to include this galaxy. Surprisingly, neither of us could find it in a
>10" f/6 dob and 20x80 binos. I now read that this is a famous object, and
>that it can be challenging to observe because of it's low surface
>brightness. Maybe with what I have read this morning we could now locate
>it, but we sure couldn't last night. I am definitely going to try again the
>next chance I get.
Hi Dennis (and the rest of saa!),
I would like to take this opportunity to suggest that the collective
participants of saa place Barnard's Galaxy, NGC 6822 (RA 19h 44.9' Dec
-14 48') on their "official saa observing list". Those up to the
task are asked to observe (or attempt to observe) this object with
whatever instrument they choose to use, and post an observing report
specifying instrument, sky conditions, object description, etc.
Negative as well as positive reports are encouraged.
IMHO it would be great for saa to do the same with a different object
every week or so. By so doing we'll get to know each other better as
observers -- including a little about individual equipment and sky
conditions. This will also be a great way of adding on-topic postings
to our beloved newsgroup! Keep in mind when selecting new objects
that not everyone has dark skies or large telescopes. Planetary,
lunar, double star, and solar features, etc. are fair game as well.
If someone prefers to omit certain equipment details or other
information, that's OK. Participation is the greater goal.
If I get a suitable observing window I'll see what I can do with
Barnard's Galaxy. Yesterday evening I had a scope set up and ready to
go; but clouds came along with a trace of rain, some thunder, and
lightning (spelled correctly this time!)
Willie R. Meghar
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Date: 24 Jul 2006 13:28:07
From: Dennis Woos
Subject: Re: Observing Barnard's Galaxy (NGC6822)
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> I would like to take this opportunity to suggest that the collective
> participants of saa place Barnard's Galaxy, NGC 6822 (RA 19h 44.9' Dec
> -14 48') on their "official saa observing list". Those up to the
> task are asked to observe (or attempt to observe) this object with
> whatever instrument they choose to use, and post an observing report
> specifying instrument, sky conditions, object description, etc.
> Negative as well as positive reports are encouraged.
>
> IMHO it would be great for saa to do the same with a different object
> every week or so. By so doing we'll get to know each other better as
> observers -- including a little about individual equipment and sky
> conditions. This will also be a great way of adding on-topic postings
> to our beloved newsgroup! Keep in mind when selecting new objects
> that not everyone has dark skies or large telescopes. Planetary,
> lunar, double star, and solar features, etc. are fair game as well.
>
> If someone prefers to omit certain equipment details or other
> information, that's OK. Participation is the greater goal.
>
> If I get a suitable observing window I'll see what I can do with
> Barnard's Galaxy. Yesterday evening I had a scope set up and ready to
> go; but clouds came along with a trace of rain, some thunder, and
> lightning (spelled correctly this time!)
>
> Willie R. Meghar
I am all for this idea. Things have been pretty bad here lately with all of
the off-topic junk, and I bet that I am not the only one who has wondered
whether it is not time to find another venue. Maybe an observing
list/challenge will help to move these discussions in a more
positive/interesting direction. I hope some folks add some exciting objects
to the list for this week - maybe I can observe some of them at Stellafane!
How about a dark nebula? BTW, we are not taking any optics to Stellafane
this year, as we are going to spend as much time as we can looking through
other people's stuff. This is not something we have done before.
Dennis
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Date: 30 Jul 2006 15:56:40
From: Bill Cotten
Subject: Re: Observing Barnard's Galaxy (NGC6822)
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"Willie R. Meghar" <NoMail@thisaddress.net > wrote in message > Hi Dennis
(and the rest of saa!),
>
> I would like to take this opportunity to suggest that the collective
> participants of saa place Barnard's Galaxy, NGC 6822 (RA 19h 44.9' Dec
> -14 48') on their "official saa observing list".
Be sure to add the large but hard to detect globular ngc 7492 to the list!
Bill
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Date: 24 Jul 2006 07:34:44
From:
Subject: Re: Observing Barnard's Galaxy (NGC6822)
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Dennis Woos wrote:
> Anybody have any reports/tips on observing Barnard's Galaxy? ...
> I now read that this is a famous object, and that it can be challenging
> to observe because of it's low surface brightness.
What you said -- it can be challenging to observe because of its low
surface brightness. The fact that it's pretty low in the sky as seen
from
most of the U.S. doesn't help either. Don't even *think* about
observing
it from the suburbs. It's possible under semirural skies (mag 21.0 per
square arcsec on the Sky Quality Meter) but *much* easier under truly
dark skies, where it stands out surprisingly well in an 8-inch scope.
Some people have reported seeing it in binoculars, but I've never
succeeded with anything smaller than 4" aperture.
As for the object itself, it's large (about 15'), amorphous, and
utterly
lacking any bright concentration. Stands out best at around 100X,
in my experience.
- Tony Flanders
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Date: 24 Jul 2006 08:45:24
From: John Banister
Subject: Re: Observing Barnard's Galaxy (NGC6822)
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I had almost exactly the same experience around 01:00 CST (06:00 GMT) last
night. I didn't take out a star chart, but my Go-To's were spot on last
night, so I am fairly confident I had the correct location. I dialed in
6822 and nothing. Just stars. I was wondering if the coordinates in my
Celestron hand controller were off or the advertised magnitue (9) was in
error. Seeing and darkness at my site were excellent all night long. I
even acquired Pluto, which is around mag 14.
-John
"Dennis Woos" <dpwoos@gmavt.net > wrote in message
news:12c9db7eehhdr24@corp.supernews.com...
> Anybody have any reports/tips on observing Barnard's Galaxy? Last night a
> friend and I looked at the planetary nebula ngc6818, and thought it would
> be easy to include this galaxy. Surprisingly, neither of us could find it
> in a 10" f/6 dob and 20x80 binos. I now read that this is a famous
> object, and that it can be challenging to observe because of it's low
> surface brightness. Maybe with what I have read this morning we could now
> locate it, but we sure couldn't last night. I am definitely going to try
> again the next chance I get.
>
> Dennis
>
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Date: 24 Jul 2006 14:45:03
From: CNJ999
Subject: Re: Observing Barnard's Galaxy (NGC6822)
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Indeed, Barnard's galaxy is an object suited mainly for those observing
under (what today has to be regarded as) very dark skies. Even a small
degree of light pollution illuminating the sky in this object's
direction will hide it completely.
That said, several decades ago, when my skies were still pristine, I
could detect the galaxy without any great difficulty using handheld
20x80 binoculars. Likewise, during my lomg ago comet hunting sessions
it was picked up regularly in sweeping with my 20x120 binoculars. Yet,
wityh my 32-cmL it was all but invisible.
The galaxy is far larger looking than most observers anticipate and in
a moderate to large telescope, can easily fail to have sufficient
surrounding dark sky in the same field to contast with, making the
object all but impossible to see.
If you wish to attempt this challenging object, be sure you have very
dark, pure skies (that rules out urban and suburban locations
completely) and an instrument better suited to looking at comets rather
than the typical run of deep sky objects.
JBortle
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Date: 25 Jul 2006 11:21:02
From: John Banister
Subject: Re: Observing Barnard's Galaxy (NGC6822)
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Well, here's my tail of woe, part 2. Last night (7/24/06, 2300L CDT, 0400
GMT) I gave Barnard's a try in a 10" newt (F4.7). I could make out Eta Ursa
Minor and the lagoon nebula with the naked eye (direct vision), so my skies
were at least mag 6. However, they were not particularly dark, probably due
to below average (2/5) transparency and the lights of Dallas 75 miles to the
southwest. I could make out the lanes in the Milky Way unaided. Seeing was
average varying between 2/5 and 3/5.
Anyway, I used a star chart to refine my Go-To and located the exact
position of Barnard's. Using eyepieces giving 40x, 60x, 80X and 133X I
could not break out anything other than the background stars. I also put on
my light polution filter on my 20mm (60X) and, at one point, I thought I had
a dim oval for less than a second, but never could get it back. I certainly
could not confirm anything.
For context, that same night I did acquire the Crescent (dim) and the dark
area Bernard 86 next to NCG6520.
I will continue trying. Maybe if you folks in Dallas would turn off your
lights at night. <G >
-John
"CNJ999" <jbortle@aol.com > wrote in message
news:1153777503.194443.320500@m79g2000cwm.googlegroups.com...
>
> Indeed, Barnard's galaxy is an object suited mainly for those observing
> under (what today has to be regarded as) very dark skies. Even a small
> degree of light pollution illuminating the sky in this object's
> direction will hide it completely.
>
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Date: 24 Jul 2006 11:38:22
From: oriel36
Subject: Re: Observing Barnard's Galaxy (NGC6822)
|
Dennis Woos wrote:
> > I would like to take this opportunity to suggest that the collective
> > participants of saa place Barnard's Galaxy, NGC 6822 (RA 19h 44.9' Dec
> > -14 48') on their "official saa observing list". Those up to the
> > task are asked to observe (or attempt to observe) this object with
> > whatever instrument they choose to use, and post an observing report
> > specifying instrument, sky conditions, object description, etc.
> > Negative as well as positive reports are encouraged.
> >
> > IMHO it would be great for saa to do the same with a different object
> > every week or so. By so doing we'll get to know each other better as
> > observers -- including a little about individual equipment and sky
> > conditions. This will also be a great way of adding on-topic postings
> > to our beloved newsgroup! Keep in mind when selecting new objects
> > that not everyone has dark skies or large telescopes. Planetary,
> > lunar, double star, and solar features, etc. are fair game as well.
> >
> > If someone prefers to omit certain equipment details or other
> > information, that's OK. Participation is the greater goal.
> >
> > If I get a suitable observing window I'll see what I can do with
> > Barnard's Galaxy. Yesterday evening I had a scope set up and ready to
> > go; but clouds came along with a trace of rain, some thunder, and
> > lightning (spelled correctly this time!)
> >
> > Willie R. Meghar
>
> I am all for this idea. Things have been pretty bad here lately with all of
> the off-topic junk, and I bet that I am not the only one who has wondered
> whether it is not time to find another venue. Maybe an observing
> list/challenge will help to move these discussions in a more
> positive/interesting direction. I hope some folks add some exciting objects
> to the list for this week - maybe I can observe some of them at Stellafane!
> How about a dark nebula? BTW, we are not taking any optics to Stellafane
> this year, as we are going to spend as much time as we can looking through
> other people's stuff. This is not something we have done before.
>
> Dennis
Here is a dark nebula picture taken by Hubble -
http://upload.wikimedia.org/wikipedia/commons/4/46/Horsehead-Hubble.jpg
Astronomy is a bit more than the satisfaction of locating a celestial
object,if it were that alone there would be no need of
Ptolemy,Copernicus or Kepler.
These great men could form a picture of planetary motion and rework it
in their heads to come up with satisfying solutions.You have time
lapse footage to do it for you and you still cannot arrive at the right
conclusions or adopt the awful mutations of the empiricists.
Do you think your pathetic appeal for astrophotography gives you the
right to call yourself an astronomer.Create a group called
astrophotography and discuss optics to your heart's content but what
you do now is not and never was astronomy proper.
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Date: 25 Jul 2006 14:55:40
From: Regina Roper
Subject: Re: Observing Barnard's Galaxy (NGC6822)
|
On Mon, 24 Jul 2006 07:56:20 -0400, "Dennis Woos" <dpwoos@gmavt.net >
wrote:
>Anybody have any reports/tips on observing Barnard's Galaxy? Last night a
>friend and I looked at the planetary nebula ngc6818, and thought it would be
>easy to include this galaxy. Surprisingly, neither of us could find it in a
>10" f/6 dob and 20x80 binos. I now read that this is a famous object, and
>that it can be challenging to observe because of it's low surface
>brightness. Maybe with what I have read this morning we could now locate
>it, but we sure couldn't last night. I am definitely going to try again the
>next chance I get.
>
>Dennis
>
Ok: here's an observation "hot off the press" -- and I do mean HOT! My
wife was too pooped out from the 100 d+ temperatures in the Santa
Clara valley to join me last night/this morning but I had seen the
post about the gx and made a point of observing it, on private
property in the mountains between San Jose and Santa Cruz. I haven't
looked at it in at least 6 years. (I must say that it is
disconcerting to be observing on top of a mountain without my usual
wintry clothes, even in summer. The temperature all night long never
dropped below about 80, and it was close to 90 while I was looking at
the gx.)
Using a C-11 in superb, steady seeing after midnight, local time, the
gx was distinctly visible when the field was acquired. Naked eye
magnitude in the Sagittarius region was about 6, there being a bit of
fog at lower elevations and pouring inland from the Pacific, cutting
off some of the light from Hollister, Gilroy, and Santa Cruz. I have
seen the gx much better at this site, but not since about 1990.
Without any filter, the apparent diameter -- in an eyepiece that
yields a measured FOV of 27 arcminutes -- was about 5-6 mins. Adding
a SkyGlow general LPR filter improved that considerably. My guess is
that I could trace it out for a diagonal of about 8-9 mins, -- but
just barely, the edges blending absolutely continuously into the
background. The visual diameter is considerably less that its
official measurement or the way it looks in a photo. I have seen it
"to the edge" in a pitch black sky with no light pollution, using a
Celestron Comet-Catcher f3.3 five inch aperture telescope; in the C-11
(not an ideal instrument for it) the gx was still pretty pale and
indistinct: not an object that you'd really notice if you moved across
the field without expecting it. Because I was *exactly* on the
coordinates, and had a HGS plot with me, I could verify after a while
that I was seeing it, which took me at least a minute or so to become
absolutely certain: my estimation of its surface brightness during
this particular (mediocre) observation was that the Calif. Nebula
looks much more distinct than this, in my 3" refractor in a dark sky.
Yet, there was enough light from it to tell that there was a sort of
mottled, rough surface, at least in the somewhat brighter center: a
bit less smooth, and choppier, than (say) a vague, bluish reflection
nebula such as the light halo around the Iris Nebula (NGC 7023).
As somebody said, there is no WAY you could see this in an urban
environment.
Adding more filtration did not yield the H-II regions but I definitely
had a sense that there was a speckling, a stellaring, to the overall
glow at the center for a diameter of about 3 mins. or so.
The object may be a bit vague and indistinct, but all in all, the gx
is much more easily perceived than Leo 1, which I once wrote about
observing here, perhaps 10 years ago or thereabouts.
I tried viewing 6822 at first with a 21 mm Stratus; then went to a 40
mm with filter, and determined that a 25 mm ocular yielded about the
best contrast; nothing shorter than 21 was useful: so my exit pupils
were in the range of 2 to 4 mm. I had no long focal length 2" ocular
beyond 42 mm, so I wished it had been possible to bring my 4" RFT with
me; but perhaps the sky just wasn't dark enough and the extra aperture
was really beneficial. However I think that a good telescope of 4-5
inches aperture will work at low power in a truly dark sky for this
gx. In fact, I do not believe that I had ever seen it with an
aperture greater than 8" until today's observation. You really need
optics that can give you about a degree of field to see the low
contrast of this spread out object effectively. (I seem to have the
feeling that I once saw it -- marginally -- in the lowest power
available in my old Astroscan, in a 3d FOV at 16x.)
At any rate, there is no wonder that it took a guy like Barnard to
discover it, and to be sure he wasn't just seeing general background
milkiness: what he called "luminous ground". I seem to have a dim
memory of coming on Barnard's own announcement of this, which might
have been in the "Astronomisches Nachrichten", in his original
announcement, written in English. Perhaps a historical minded
enthusiast could fill us in; I haven't had time to look up more info
as I am ready for some shut-eye!
Srw
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Date: 25 Jul 2006 11:29:20
From: Dennis Woos
Subject: Re: Observing Barnard's Galaxy (NGC6822)
|
Thanks for the report. I too tried to observe it last night, and a friend
and I thought that we could barely detect it in a 10" f/6 dob with a 35 Pan.
This is a target that we will revisit on great nights, and certainly when we
are observing at darker sites.
Dennis
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Date: 25 Jul 2006 18:32:09
From: Regina Roper
Subject: Re: Observing Barnard's Galaxy (NGC6822)
|
On Tue, 25 Jul 2006 14:55:40 GMT, Regina Roper
<AstroApp@***blocked***.net > wrote:
>At any rate, there is no wonder that it took a guy like Barnard to
>discover it, and to be sure he wasn't just seeing general background
>milkiness: what he called "luminous ground". I seem to have a dim
>memory of coming on Barnard's own announcement of this, which might
>have been in the "Astronomisches Nachrichten", in his original
>announcement, written in English.
...after two and a half hours of rest, I am conscious enough to think
a bit more about NGC 6822 and make this addendum:
Just after making the previous post I did a quick Google search and
could not help but note that the scope used by Barnard to discover the
gx is first a 5 inch...then a 6...then perhaps a 5, a 6, a 5 again and
so forth, as the factoids creep, one website quoting another one at
random.
It could have been EITHER a 5 or 6 but my recollection is that EEB had
a 5" comet hunter that he bought with his own hard-earned $$$.
However I guess at the time of the discovery he would have been at
Vanderbilt, working toward his bachelor's degree in mathematics and
full of ambition -- and he might have been using one of their
telescopes. He had for some time already achieved enough worldliness
that he was posting his observations to the major astronomy
publications, and as the discoverer by then of many comets, his
submissions were always quickly accepted and published.
Does anybody have Sheehan's bio of EEB at hand? I read it but in a
library copy and do not have it in my library. That resource would
surely have the accurate details of the discovery of 6822, as Bill
Sheehan would have covered the same materials in HIS research about
Barnard, as I did five years earlier when I researched Barnard's
involvement with the nebula that Harvard discovered that later became
catalogued by EEB as No.33: the "Horsehead". Lick's and UC/Santa
Cruz's collections had just about everything published about the
original visual discoveries of the objects that were later
incorporated into the NGC and other famous catalogues...but
unfortunately, in recent years much of those old mouldering volumes
and bound copies of periodicals have been put into storage: that same
research would be nearly impossible to achieve today, in the same
relatively easy way that I did it, fifteen years ago.
The problem with all these different sites on the web briefly
referencing EEB's telescope used to find the object is that
practically none of them are going to first sources. As I learned
with my Lick research on the HH nebula, the first sources tell a
remarkably different story of what originally happened, who first
actually discovered it and recorded details about it, what EEB did to
investigate it, and so forth, than *any* website article about it that
merely tries to digest the usual umpteenth-level sources. So, I put
up my old research paper about B33 to set the record straight, quoting
the "first sources".
So, repeating: what did EEB say about his discovery of the gx, and
what instrument did he use? Sheehan would qualify as an accurate
researcher of authentic first sources: his book must have the actual
facts.
Srw
http://home.earthlink.net/~astro-app/horsehead/index.html
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Date: 25 Jul 2006 06:15:49
From: oriel36
Subject: Re: Observing Barnard's Galaxy (NGC6822)
|
CNJ999 wrote:
> Indeed, Barnard's galaxy is an object suited mainly for those observing
> under (what today has to be regarded as) very dark skies. Even a small
> degree of light pollution illuminating the sky in this object's
> direction will hide it completely.
>
> That said, several decades ago, when my skies were still pristine, I
> could detect the galaxy without any great difficulty using handheld
> 20x80 binoculars. Likewise, during my lomg ago comet hunting sessions
> it was picked up regularly in sweeping with my 20x120 binoculars. Yet,
> wityh my 32-cmL it was all but invisible.
>
> The galaxy is far larger looking than most observers anticipate and in
> a moderate to large telescope, can easily fail to have sufficient
> surrounding dark sky in the same field to contast with, making the
> object all but impossible to see.
>
> If you wish to attempt this challenging object, be sure you have very
> dark, pure skies (that rules out urban and suburban locations
> completely) and an instrument better suited to looking at comets rather
> than the typical run of deep sky objects.
>
> JBortle
If you wish to attempt this challenging object go to Hubble images -
http://nssdc.gsfc.nasa.gov/image/astro/hst_ngc6822_0101.jpg
What a challenge !,perhaps searching for stationary objects in a
celestial sphere taxes the intelligence of photographers in which case
birdwatching is far more challenging.
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Date: 26 Jul 2006 00:13:45
From: Florian
Subject: Re: Observing Barnard's Galaxy (NGC6822)
|
> Anybody have any reports/tips on observing Barnard's Galaxy?
Hi Dennis,
As others have said dark skies are the key. From the Cottonwood campground in Joshua Tree nat park i find 6822 fairly easily with 16x70 binoculars. Easier than through a telescope as it stands out better with a wide field. I _think_ i've seen it through handheld 10x42 binoculars but don't actually find that observation in my notes so i can't state for sure.
-Florian
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Date: 25 Jul 2006 12:47:35
From:
Subject: Re: Observing Barnard's Galaxy (NGC6822)
|
Regina Roper wrote:
> Just after making the previous post I did a quick Google search and
> could not help but note that the scope used by Barnard to discover the
> gx is first a 5 inch...then a 6...then perhaps a 5, a 6, a 5 again and
> so forth, as the factoids creep, one website quoting another one at
> random.
For facts *with* attribution, type "NGC 6822" into
www.ngcic.org/pubdb.htm
- Tony Flanders
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Date: 26 Jul 2006 01:39:47
From: Regina Roper
Subject: Re: Observing Barnard's Galaxy (NGC6822)
|
On 25 Jul 2006 12:47:35 -0700, tony_flanders@yahoo.com wrote:
>Regina Roper wrote:
>
>> Just after making the previous post I did a quick Google search and
>> could not help but note that the scope used by Barnard to discover the
>> gx is first a 5 inch...then a 6...then perhaps a 5, a 6, a 5 again and
>> so forth, as the factoids creep, one website quoting another one at
>> random.
>
>For facts *with* attribution, type "NGC 6822" into
>www.ngcic.org/pubdb.htm
>
> - Tony Flanders
So, it would seem that Barnard discovered it with a 5 inch refractor
(recounted in Sheehan) and then measured its position with the 6 inch
scope. I think that I read the original report by EEB in Lick's old
copy of the Sidereal Messenger, which was also reprinted, in English,
in Astronomisches Nachrichten; I may indeed have viewed both of those
in 1989-90 during my search of all the Barnard observations preserved
in the Lick archives.
Even to Barnard himself, the object was "exceedingly faint"; so none
of us today should be dismayed by its vagueness and ethereal quality
to the eye.
Thanks, Tony.
Srw
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Date: 26 Jul 2006 04:28:22
From:
Subject: Re: Observing Barnard's Galaxy (NGC6822)
|
Regina Roper wrote:
> So, it would seem that Barnard discovered it with a 5 inch refractor
> (recounted in Sheehan) and then measured its position with the 6 inch
> scope.
Maybe. Or maybe Barnard was confused about which scope he used.
It's happened to me, it could certainly happen to him. It also seems
worth checking with Sheehan to find out where he gots his info. Even
the most careful authors make mistakes.
- Tony Flanders
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Date: 26 Jul 2006 18:59:33
From: Regina Roper
Subject: Re: Observing Barnard's Galaxy (NGC6822)
|
On 26 Jul 2006 04:28:22 -0700, tony_flanders@yahoo.com wrote:
>Regina Roper wrote:
>
>> So, it would seem that Barnard discovered it with a 5 inch refractor
>> (recounted in Sheehan) and then measured its position with the 6 inch
>> scope.
>
>Maybe. Or maybe Barnard was confused about which scope he used.
>It's happened to me, it could certainly happen to him. It also seems
>worth checking with Sheehan to find out where he gots his info. Even
>the most careful authors make mistakes.
>
> - Tony Flanders
Well, memory can be faulty. But I did spend several months doing
research on Barnard's observations, using the resources of the Mary
Lea Shane archives, the UC/Santa Cruz scienc library, and of its
specific Lick astronomy collections. They had the SIderal Messenger,
AN,ApJ, etc. -- even original copies of Dreyer's first editions of the
NGC and IC. The collection was started by Holden when he was hired as
Director of Lick Observatory and though he was able to get some older
materials, but generally the actual physical copies of their
publications were not much older than the 1870s.
I was interested to know if EEB had made any visible observations of
the region containing the HH nebula. So I looked at ALL the EEB
publications of visuall discoveries and observations, going thru all
the relevant publications, issue by issue. There were a LOT of them,
and I recalled specifically reading about his discovery of what we now
call NGC 6822 -- but since I read it in those old volumes nearly 20
years ago, all I could recall *precisely* was that he did use a small
refractor: so when I saw many websites say "5" or "6", and even
deviate by a couple of years on the date discovered, I could not be
certain, FROM MEMORY, about what I had read: it could be a 5, could be
a 6; and I was not certain if it was 1884 or 1886...but I knew it was
before EEB came to work at Lick, as well as having occurred after he
had become known to the astronomical community -- amateur AND pro --
as a prodigious discoverer of comets (a fame which basically got him
his post at Lick.)
Now, Bill Sheehan is not a professional astronomer -- I believe he is
a physician -- but he is an amateur scientist and amateur historian of
the FIRST RANK.
Bill and I were both mentored by Dr. Don Osterbrock, former Director
of Lick and professor emeritus of astrohysics at UC/Santa Cruz.
However, Bill and I have never actually crossed paths; I was doing
similar reseach, with the same sets of documents, a few years before
Bill did his investigations. And my subject was narrower.
I have read all of BIll's astronomical books and since I also saw the
FIRST SOURCES for what he describes in his historical accounts of
things that happened at Lick, involving Lick astronomers and visiting
scientists, I can tell you that he is a very trustworthy researcher.
Now, somebody can pathologically suggest that, therefore, *BOTH* Bill
and I are wrong...but it's easy to find that out: just "do the
experiment". Look at the documents.
Bill is not directly quoted in the description page of the NGC/IC
Project for NGC 6822; he is paraprased, and not very explicitly. I do
not remember EXACTLY what he said in his book; it's at a library about
25 miles from me -- if it is on the shelves at this moment -- and I
could go there and check, or look at a copy if I find one at my
nearest Borders (but, sadly, I don;t think any of the San Jose or
lower SF peninsula stores have "The Immortal Fire Within" at present.)
I hope, Tony, that you are not asserting that Bill Sheehan is a poor
scholar. I chuckled at your mistype: "where he gots his information";
of course it is a miniscule human error and one that, sadly, I commit
ALL THE TINE...err, TIME. No matter. But I can assure you that, in
my experience comparing HIS books with the original papers and
articles I've seen with my own two eyes, that Bill is a careful
researcher, an honest one, and is probably even a better "self editor"
than you, Tony, or me!
And Don Osterbrock has a high opinion of Bill's work, too.
Cordially,
Steve W.
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Date: 26 Jul 2006 02:39:43
From: Willie R. Meghar
Subject: Re: Observing Barnard's Galaxy (NGC6822)
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I finally got a chance to look for Barnard's Galaxy!
Shortly before sunset I set up a tripod and mount for my 13cm (5.1
inch) refractor; but as the sky was darkening clouds came and started
looking a bit threatening. I brought the tripod and mount back inside
and decided to periodically check conditions for a possible observing
opportunity.
Finally some clearings appeared and I decided to set up a pair of
25x100 binoculars on a tripod and mount on my south porch (I wanted to
be able to quickly get things back inside in case of rain, etc.)
Clouds covered the desired piece of sky after I was ready to start
observing; so I had to wait once again. Eventually clouds moved out
of the way and I was able to find my way to the galaxy. My binocular
mount has a 1x red-dot finder on it to simplify aiming. As soon as I
found the correct field of view I saw the galaxy!
NGC 6822 was relatively faint. The galaxy-sky boundary was very
diffuse. The galaxy appeared to be a roughly disk-shaped stain on the
background sky. It appeared to be just under a quarter of a degree in
diameter without any visible internal structure. I could pan the
binoculars in azimuth, pan back and spot the galaxy without much
difficulty once it came back into the field of view.
Next I tried a pair of hand-held 20x80 binoculars. The galaxy was
definitely visible in the 20x80s; but it was fainter and more
difficult than it was with the 25x100s. A mount may or may not have
helped with the 20x80s.
Next I tried a pair of 7x50 and 8x42 binoculars. I was unable to
positively see the galaxy with these smaller binoculars.
Distant lightning brightened the sky on rare occasions while I was
observing. My NELM was 6.5. Clouds were darker than the background
sky. My latitude is between 45 and 46 degrees north. I made use of
three atlases (that I kept inside as I ventured in and out using only
a dim red light). The Cambridge Star Atlas was used to get 'in the
ballpark'. The Uranometria was used to pinpoint the correct field of
view. The Millennium was used to estimated the galaxy's size. As it
turned out, the symbol for the galaxy in the Millennium Atlas was just
*slightly* smaller than what I estimated it to be as seen with the
large binoculars.
Willie R. Meghar
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Date: 26 Jul 2006 10:38:40
From: Willie R. Meghar
Subject: Re: Observing Barnard's Galaxy (NGC6822)
|
Please note one correction that should be made to the observing report
I posted earlier this morning. I had written in that report:
>As it
>turned out, the symbol for the galaxy in the Millennium Atlas was just
>*slightly* smaller than what I estimated it to be as seen with the
>large binoculars.
When corrected, the above should read:
"As it turned out, the symbol for the galaxy in the Millennium Atlas
was just *slightly* larger than what I estimated it to be as seen with
the large binoculars."
The difference in size was hardly enough to be relevant, especially
since my estimate could have been off by enough to make up the
difference. For all practical purposes one could go with the plotted
symbol in the Millennium and get a very close to reality depiction of
the galaxy's actual apparent size and shape.
If I get a more cooperative night soon (tonight maybe?) I'll see how
my 13cm (5.1 inch) f/6 apochromat does on this galaxy. I'm reasonably
confident that this refractor will reveal NGC 6822 without much
difficulty -- as long as I'm careful in selecting the right
eyepiece(s).
Willie R. Meghar
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Date: 26 Jul 2006 12:44:43
From:
Subject: Re: Observing Barnard's Galaxy (NGC6822)
|
Regina Roper wrote:
> Now, Bill Sheehan is not a professional astronomer -- I believe he is
> a physician -- but he is an amateur scientist and amateur historian of
> the FIRST RANK . ..
>
> I hope, Tony, that you are not asserting that Bill Sheehan is a poor
> scholar.
Yikes! I am well aware how careful and scrupulous Bill Sheehan is --
definitely one of the most reliable history-of-astronomy writers
around.
But as I said, even the most careful authors make mistakes. I've
seen that time and time again.
I was just somewhat taken aback by the fact that those few sentences
on the NGC/IC site changed you from being apparently quite unsure
of the situation to being completely certain. Especially since Corwin
--
or whoever wrote that -- seemed to have doubts of his own.
I suppose that to make amends, I ought to dig up Sheehan's biography
of Barnard and see exactly what it says. Which I'll do if time permits
...
- Tony Flanders
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Date: 30 Jul 2006 15:52:08
From: Bill Cotten
Subject: Re: Observing Barnard's Galaxy (NGC6822)
|
"Dennis Woos" <dpwoos@gmavt.net > wrote in message
news:12c9db7eehhdr24@corp.supernews.com...
> Anybody have any reports/tips on observing Barnard's Galaxy? Last night a
> friend and I looked at the planetary nebula ngc6818, and thought it would
> be easy to include this galaxy. Surprisingly, neither of us could find it
> in a 10" f/6 dob and 20x80 binos.
Don't feel bad. I picked it up in 7x50 binos one night so we tried to use
the 41.25" on it and had no luck at all despite being visible in binos the
whole time. This low surface brightness is also common with M33.
Bill
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