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#1 kenrenard

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Posted 27 December 2012 - 06:42 AM

I received two books for christmas.
Steve O'Meara's Herschel 400 Observing Guide and the Messier Objects. Both are great books.

My question is can the Hershel 400 be completed with an 8 inch dob from a light polluted area? I am working through the Messier objects from my backyard and have been able to get about 50 so far with my 72mm scope. I understand O'Meara used a 4 inch refractor for the Hershel, but he was in great skies and is a world class observer.

If not and 8 inch how big in aperture is needed. I read in some of the other forums aperture is your friend in suburban skies. Just curious of people's thoughts. Thanks

#2 Tony Flanders

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Posted 27 December 2012 - 07:44 AM

Can the Hershel 400 be completed with an 8 inch dob from a light polluted area?


Depends how bad the light pollution is. I found most of the Herschel 400 with my 7-inch Dob from my astronomy club's observing field in the Boston exurbs. However, a few of the fainter galaxies required trips to darker locations.

A fair number of Herschel 400 objects are extremely bright and obvious -- for instance, the Double Cluster. And probably more than half are easier than the toughest Messier objects. But there are also a few toughies in there ... at least for an 8-inch scope.

Obviously, any galaxy looks a lot more interesting under dark skies than from a suburban backyard.

#3 kenrenard

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Posted 27 December 2012 - 08:54 AM

Thank You Tony,
I belong to a local Astronomy club which has pretty dark skies. Can see the Milky Way naked eye on most nights. However, seems every time we have a club night its either raining or cloudy. I have two small children so I end up doing most of my observations from my backyard which isn't bad after everyone goes to bed in the neighborhood.

I am working on sketching each of the Messier objects and have been able to get some really nice detail on quite a few.

By the way, Love your skyweek segments. I have learned quite a bit over the past year just by watching your weekly segments and reading your articles. Keep up the good work.

#4 City Kid

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Posted 27 December 2012 - 09:37 AM

My question is can the Hershel 400 be completed with an 8 inch dob from a light polluted area?


I doubt if you'll be able to complete the H400 from light polluted skies but you'll certainly be able to log quite a few of them. When I worked my way through the list I was surprised at how many were visible from my light polluted backyard. Of course "light polluted" can mean different things to different people. In my backyard the Milky Way is completely invisible even on the most pristine of nights.

#5 blb

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Posted 27 December 2012 - 10:04 AM

I belong to a local Astronomy club which has pretty dark skies. Can see the Milky Way naked eye on most nights. However, seems every time we have a club night its either raining or cloudy.


If you can see the Milky Way naked eye, you will be able to complete the Herschel 400 with an 8" if you have the experance. I would finish the Messier list to gain enough experance to be able to complete the Herschel 400. Some of the objects are tough for a beginner.

I have the same problem on club observations, sometimes I feel like becomming a cloud watcher. Still I can go to our club field on other nights and observe, Maybe you can too. ;)

#6 vsteblina

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Posted 27 December 2012 - 10:13 AM

I think it really depends on your objective.

If you want to spot the h400 a small scope will work from a dark site.

I used a 17.5 from a dark site in most cases and wished I had more mirror for the more interesting objects.

#7 kenrenard

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Posted 27 December 2012 - 10:15 AM

Of course "light polluted" can mean different things to different people. In my backyard the Milky Way is completely invisible even on the most pristine of nights.


I have been able to view the milky way just barely on one night of extreme good seeing. However it was very very faint. Light Pollution really is a shame it ruins the sky for all of us. Thanks for your reply.

#8 kenrenard

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Posted 27 December 2012 - 10:18 AM

Thank You Buddy,
I am working my way through the Messier. I am going to check out your blog. I just started sketching and I am really picking out more detail than before I sketched.

I've had one or two memorable nights at our club site with great views, but in the Northeast its often anyones guess on the weather.

#9 Dave Mitsky

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Posted 27 December 2012 - 01:44 PM

If you can see the Milky Way naked eye, you will be able to complete the Herschel 400 with an 8" if you have the experance. I would finish the Messier list to gain enough experance to be able to complete the Herschel 400. Some of the objects are tough for a beginner.


I wouldn't make that claim. Despite repeated attempts, I was unable to see NGC 6118, the so-called Blinking Galaxy, using a 17" classical Cassegrain at a site where the summer Milky Way was slightly visible and a 20" classsical Cassegrain at a somewhat darker site. I finally logged it under the dark skies of Stellafane with an 8" Newtonian.

Dave Mitsky

#10 kenrenard

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Posted 27 December 2012 - 02:05 PM

I am really understanding that dark skies make all the difference. This summer I took a trip to visit a relative in the Catskills. That night I had my 72mm refractor and I could not believe all I could see. Unfortunately I only spent about 2 hours since we were visiting. I also became almost disoriented because I had never been in skies so dark. I saw so much I couldn't make out some constellations because so many stars were visible. I just remember seeing the Milky Way painted across the whole sky. I wish I had my dob, but with two small kids and my wife and luggage it just wouldn't fit.

I do see the advantages of large scopes but for me I think I need to look for something in between the 8 inch and the 72mm that won't break the bank. For the times when we can travel to dark skies.

I thank you all for your input and look forward to working on viewing some of the Hershel objects.

#11 Tony Flanders

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Posted 27 December 2012 - 03:39 PM


If you can see the Milky Way naked eye, you will be able to complete the Herschel 400 with an 8" if you have the experance. I would finish the Messier list to gain enough experance to be able to complete the Herschel 400. Some of the objects are tough for a beginner.


I wouldn't make that claim.


Agreed. Being able to see the Milky Way is a very low bar indeed. The summer Milky Way is readily visible from many heavily light-polluted sites in Boston's inner suburbs. The Milky Way is visible in every season except spring from my astronomy club's observing field.

But as Dave says, NGC 6118 and a few other galaxies in the Herschel 400 require significantly darker skies than that even with a big scope, and certainly with an 8-inch scope.

#12 blb

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Posted 27 December 2012 - 11:47 PM

But as Dave says, NGC 6118 and a few other galaxies in the Herschel 400 require significantly darker skies than that even with a big scope, and certainly with an 8-inch scope.


Yes there are a few that will be hard to see without dark skies, but let's not forget that this list was developed for an 8-inch telescope, and that O'Meara used a 4-inch refractor for his book on the Herschel 400, also that J. Reynlods Freeman observed them all with a 55mm refractor too. Yes there are those objects that will need darker skies but that is the fun of it, trying to observe in not quite the best skies. You of all people know that much can be seen even in Boston with it's light pollution. So let's not discourage but reather encourage the effort with the knowledge that you may need to travel to darker skies for some objects.

#13 Dave Mitsky

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Posted 28 December 2012 - 12:49 AM

There is a big difference between being discouraging and being realistic. Some of the H400 objects are going to be very difficult from a light-polluted locale and some will be simply impossible to see.

My first-and-not-very-impressive view of NGC 6118 took place during the 1998 Stellafane convention.

http://www.visualdee...s/msg00879.html

Here's an excerpt from a previous post of mine on Cloudy Nights:

I had relatively little trouble with NGC 6540, which was the second most difficult H400 object according to some sources, but my first sighting of NGC 6118* absolutely required dark skies.

In June of 2002, my friend Tony Donnangelo, who is a truly first class observer, and I saw no hint of NGC 6118 through his 10" Meade LX5 SCT under slightly better than sixth magnitude skies at an ASH dark site in western Perry County, Pennsylvania. I've had no success with detecting NGC 6118 from Cherry Springs State Park, the IDA's second International Dark Sky Park, with my 101mm Tele Vue refractor. The Blinking Galaxy is visible through larger apertures from that location, of course.

Ed Ting relates his experience with observing NGC 6118** from a dark site in Arizona at http://www.scopereviews.com/az.html

"Halfway through the night, I laid some time aside to look for NGC 6118 in Serpens, which is roundly considered the most difficult Herschel object of them all. It's a relatively large galaxy with almost no surface brightness. Many experienced observers go their whole lives without seeing it. On this night, I found NGC 6118 in about thirty seconds. It looks a little bit like M33 does in my TeleVue Ranger under modest light pollution."

Here's what Jay Reynolds Freeman had to say about NGC 6118 and NGC 6540 during his quest to observe the Herschel 400 with a 55mm refractor:

"NGC 6118 lies in eastern end Serpens Caput, near a sixth-magnitude star (which is actually in Ophiuchus), about two degrees south of the celestial equator. That star was visible to the naked eye, and even if it hadn't been, nearby lambda, epsilon, and delta Ophiuchi made the field easy to locate. I observed with two eyepieces, alternating between a 12 mm Brandon (37x) and a 20 mm Meade Research Grade Erfle (22x). I used the _Millennium_Star_Atlas_, which shows plenty of nearby stars, so the precise location of the object was not in doubt.

With each of the eyepieces, I saw a faint, diffuse, and not very centrally concentrated glow, popping in and out at the limit of averted vision, at the charted position. Jiggling the telescope, or moving it slightly with the slow motions, helped a bit. The glow was detectable only ten or twenty percent of the time, but it kept reappearing at the same place, and I do not see similar fluctuations of intensity at random places in such fields, so I logged it.

Make no mistake -- this was a very tough object, certainly the toughest so far in my Herschel-400 survey with Refractor Red. When I say "detection", I mean no more than that. NGC 6118 would have gone unnoticed had I not known in advance exactly where to look, or had I not been patiently willing to pull every trick in my book to find it. I suspect that the root of the difficulty is that the object does not have nearly as large a central concentration to its brightness as do most galaxies; such a bright core to an image seems to draw the eye, and give the brain a reference point for locating the fainter, outer periphery of the object. Or so I would conjecture.

Since I had essentially an equally good view at 22x (2.5 mm exit pupil) and 37x (1.5 mm exit pupil), I suspect that an interim magnification -- perhaps with a 2 mm exit pupil -- might have been best for that object on that night. Unfortunately, I had only brought a handful of eyepieces, and did not have one available.

On the next evening I was at Fremont Peak again, this time with my Meade 5-inch refractor (model 127 ED). Sky conditions were similar, so I looked for NGC 6118 in the larger telescope, using 36x (Orion 32 mm Sirius Plossl) -- a magnification very similar to one of the ones I had used with Refractor Red. The object was much easier -- with five times the light grasp, that's no surprise -- and I was able to confirm the appearance that I had seen in the smaller instrument.

NGC 6540, located just off the spout of the Sagittarius "Teapot", is something of a puzzle. The visual description from the original catalog is a faint, sparse, open cluster which is relatively small in angular size. Yet what _Millennium_ plots is a ten-arc-minute globular. What I saw with the 12 mm Brandon in Refractor Red (37x) was a six or seven arc-minute unresolved circular glow, just noticeably brighter than the background (which was pretty bright -- this object is in the Sagittarius Milky Way, after all), with a smaller, brighter core superimposed. The core might have been one or two arc-minutes in diameter, it was unresolved, and it did not appear to have diffuse edges. The entire apparition was dead on the atlas position for NGC 6540, and was notably easier than NGC 6118."

* in 1998
** Ed was using a 12" Meade Starfinder Dob

Dave Mitsky

The ASH 17" f/15 classical Cassegrain, with which I observed over half of the H400 objects and one of the two large aperture telescopes with which I have never been able to see NGC 6118

http://server2.clear...ml?Mn=astronomy (CSC LP map for the Naylor Observatory)

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#14 blb

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Posted 28 December 2012 - 01:52 AM

There is a big difference between being discouraging and being realistic. Some of the H400 objects are going to be very difficult from a light-polluted locale and some will be simply impossible to see...

I do agree with you Dave. Some, no mater what scope you are using, will be dependent on sky conditions. Let me quote from the Herschel 400 observers guide put out by the Ancient City Astronomy Club for the Astronomical League's program. On page one: "All the objects can be seen in a six-inch or larger telescope. All descriptions have been taken from observations by two or more members of the ACAC; most of these observations were made within the city of St. Augustine,...in average to good sky conditions. Faintest naked eye star visible at the zenith was about 5.5 magnitude in most cases...This is ment to be an advanced project for amateurs who already have a fair degree of deep sky experience."

Even so it is amazing that Mr. Freeman was able to see NGC 6118 with just a 55mm refractor and O'Meara with his 4-inch refractor. It is also amazing that the description in the ACAC's guide was made using a 6-inch Cass. in a sky that had a naked eye limiting magniyude of 5.5, that is where the Milky Way just starts to become visible for me. Maybe these people are much better observers than we are, I don't know. So I still say try to see it and you may need to visit a darker sky site but you will not know untill you try. It is for sure that you will not know if you can see it until you try.

#15 Bill Weir

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Posted 28 December 2012 - 02:06 AM

Here's my suggestion. Forget about what others might say about difficlties of objects and just get out there and give it a go. The galaxy in question NGC 6118 was difficult with my 6" dob but certainly not the most difficult object I've ever seen with it. I do my observing from a location that more and more I consider better than most on the eastern side of the US and I consider it JUST adequate. My backyard and the observatory down the road on average have SQM readings of around 21 + or - and decimal place or two. Here's how I saw NGC 6118 in late July 2008 using my 6" dob with a 80% Moon just below the horizon. http://rascvic.zenfo...ff5f2#h3fb1f160

Sure some objects will be tough and on others you might even fail but who knows. Only you will be able to find out what is possible from your location. I suggest working both lists concurrently. Many times objects from both lists will be in the same area of the sky. That way you won't be jumping all over the place or wondering what to do if you have found the few from one list in any given area.

So get out there, do the experiment and report back your findings.

Bill

#16 kenrenard

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Posted 28 December 2012 - 06:52 AM

I do appreciate all of your honest opinions. I am by no means an experienced observer so I doubt I will see some of the objects you folks describe.

I started about a year ago when my daughter asked about planets. We ended up getting a telescope after reading some books and I fell in love with searching the sky. I didn't know more than a few constellations and had no idea who Messier or Hershel even were. With the help of members at my local Astronomy club I have learned star hopping, and viewed many of the Messier objects. Although not all. I recently started to sketch the Messier list and enjoy the hunt of finding something faint.

Once the sky clears of clouds I will start to look and work on the Hershel 400 list. I am not really in a hurry to complete it. I enjoy the quiet contemplative world of looking and observing. I get to our clubs dark site a few times a month and hope to get out to Cherry Springs state park which from what I am told has very dark skies.

I will try to start with the easy objects. Since O'Meara rates easy to hard in the book and report some of my findings.


Hope you all have clear skies.

Thanks

Ken

#17 edwincjones

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Posted 28 December 2012 - 07:56 AM

Ken,

from my experience with the AL observing clubs,
it is one step/object at a time,
get one and then another
easier first
more difficult may require darker skies

do several clubs at a time,
so if you get stuck on one list, go to another

as stated above, the 8" should do it-or at least most
if you cannot get with the 8",
then you have a good argument for a larger scope

edj

#18 kenrenard

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Posted 28 December 2012 - 08:51 AM

The ASH 17" f/15 classical Cassegrain, with which I observed over half of the H400 objects and one of the two large aperture telescopes with which I have never been able to see NGC 6118


That is one massive scope. Looks really nice.

#19 kenrenard

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Posted 28 December 2012 - 08:53 AM

Ken,

from my experience with the AL observing clubs,
it is one step/object at a time,
get one and then another
easier first
more difficult may require darker skies

do several clubs at a time,
so if you get stuck on one list, go to another

as stated above, the 8" should do it-or at least most
if you cannot get with the 8",
then you have a good argument for a larger scope

edj


Thank you Ed. I plan to work on the list and do the best I can.
If I can become a better observer I will be happy.

#20 Dave Mitsky

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Posted 28 December 2012 - 02:41 PM

There is a big difference between being discouraging and being realistic. Some of the H400 objects are going to be very difficult from a light-polluted locale and some will be simply impossible to see...

I do agree with you Dave. Some, no mater what scope you are using, will be dependent on sky conditions. Let me quote from the Herschel 400 observers guide put out by the Ancient City Astronomy Club for the Astronomical League's program. On page one: "All the objects can be seen in a six-inch or larger telescope. All descriptions have been taken from observations by two or more members of the ACAC; most of these observations were made within the city of St. Augustine,...in average to good sky conditions. Faintest naked eye star visible at the zenith was about 5.5 magnitude in most cases...This is ment to be an advanced project for amateurs who already have a fair degree of deep sky experience."

Even so it is amazing that Mr. Freeman was able to see NGC 6118 with just a 55mm refractor and O'Meara with his 4-inch refractor. It is also amazing that the description in the ACAC's guide was made using a 6-inch Cass. in a sky that had a naked eye limiting magniyude of 5.5, that is where the Milky Way just starts to become visible for me. Maybe these people are much better observers than we are, I don't know. So I still say try to see it and you may need to visit a darker sky site but you will not know untill you try. It is for sure that you will not know if you can see it until you try.


I happen to own a copy of Observe the Herschel Objects, the Astronomical League's Herschel 400 booklet. It was published in 1992. The H400 list, I believe, was compiled during the 1980s. Skies were a lot darker then. It is also crucial to keep in mind the phrase "most of these observations were made within the city of St. Augustine". Most, not all.

Of course, there is no harm in trying for oneself and I certainly recommend doing so but when someone asks for advice and seasoned observers relate their first-hand experience, why not give it some credence?

Freeman had to travel to a dark site to successfully observe NGC 6118 and O'Meara observed from excellent dark sites (at altitudes of 3600 and 4200 feet and from a very favorable southerly latitude of 19.4 degrees north on the island of Hawaii) that he describes as having "world-class skies". Both men are highly talented observers.

Here's a quote from O'Meara that I found in a review of his book on the Herschel 400: “the limit you see will vary wildly depending on your location, the clarity of the atmosphere, the degree of light pollution, your visual acuity, the time you spend looking behind the eyepiece, and your expertise."

Dave Mitsky

#21 Dave Mitsky

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Posted 28 December 2012 - 02:52 PM

Here's my suggestion. Forget about what others might say about difficlties of objects and just get out there and give it a go. The galaxy in question NGC 6118 was difficult with my 6" dob but certainly not the most difficult object I've ever seen with it. I do my observing from a location that more and more I consider better than most on the eastern side of the US and I consider it JUST adequate. My backyard and the observatory down the road on average have SQM readings of around 21 + or - and decimal place or two.


Bill,

Your observing sites ARE better than most East Coast sites. As we all know, dark skies make all the difference.

Dave Mitsky

#22 kenrenard

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Posted 28 December 2012 - 08:34 PM

Dave,
Thank you for your advice. I would not even classify myself as an novice observer so I do appreciate you and others taking the time to answer my questions. I'm not even sure how light polluted my backyard is, I know there are better times than others like 5 am once all the lights are off.

I did read a bit about Stephen O'Meara and the skies he has in his own yard. I am not familiar with Mr. Freeman but I can only imagine his skill using something the size of my finder scope.

By no means was I trying to offend anyone. After reading through the forums I could see there were some very experienced people answering the questions. When I have been able to I answer questions based on mistakes I made and misconceptions I had from my own ignorance.


One of the things I have learned over the past year is to have a plan what you want to try to observe. When i first got into it I didn't know what to look at and just roamed around looking for something interesting. If I can get through the Messier object list I thought the Hershel was a logical progression. I may be wrong to think this so please correct me if I am wrong.


Again thank all of you for your input and expertise.


Ken

#23 City Kid

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Posted 28 December 2012 - 08:59 PM

If I can get through the Messier object list I thought the Hershel was a logical progression. I may be wrong to think this so please correct me if I am wrong.

The Herschel 400 is a very logical step from the Messier list, especially if DSOs are your targets of choice.

#24 Dave Mitsky

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Posted 28 December 2012 - 09:18 PM

If I can get through the Messier object list I thought the Hershel was a logical progression. I may be wrong to think this so please correct me if I am wrong.

Again thank all of you for your input and expertise.

Ken


Well, the H400 is certainly a step beyond the Messier catalog (not list) but not necessarily the best one.

You may want to work on some of these easier "best of" lists first:

http://seds.org/mess...r/sac110bn.html

http://seds.org/mess...r/rasc-ngc.html

http://x.astrogeek.o....php?list_id=16 (sci.astro.amateur 100)

http://x.astrogeek.o....php?list_id=17 (sci.astro.amateur 200)

http://www.taas.org/...00.html?type=10

You're welcome.

Dave Mitsky

#25 kenrenard

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Posted 28 December 2012 - 09:32 PM

Wow they ought to keep me busy for a while. I am going to try to complete the Messier catalog first and try to sketch the objects I have sketched about a dozen so far, it seems to give me more detail if I try to draw the object although I am no artist.

Thanks again.






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