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NGC 6302

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#1 Scanning4Comets

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Posted 04 July 2014 - 11:32 AM

I've been looking for the visual magnitude of this planetary nebula online and I am getting lots of mixed mags.

One site says 13.0, another one says 9.6, and another says 7.1!

What's the REAL MAGNITUDE of this object?

Thanks in advance!

#2 City Kid

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Posted 04 July 2014 - 01:00 PM

I don't know what the "real" magnitude is but Uranometria, The Night Sky Observers Guide, O'Meara's book on the Caldwell Objects, and the Sky Atlas Companion all show the magnitude as 9.6.

#3 Feidb

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Posted 04 July 2014 - 08:39 PM

Megastar lists it as mag. 12.8 P.

There you go, another one. The point is, can you see it? If so, was it cool to look at? If so, log it and move on. That's what I've done, many times. The Bug is pretty cool.

#4 astroment

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Posted 04 July 2014 - 09:15 PM

Stellarium lists it at mag 13

#5 blb

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Posted 04 July 2014 - 10:08 PM

The NGC/IC web page lists the mag. as 9.6 with a blue mag. of 12.8. The problem is often that many references list the photographic mag., the blue mag or sometimes gives the visual mag. of 9.6. The magnitude should not be given unless how it was determined is stated. But hey, I agree with Fred, can you see it and if so, what do you think. It was discovered with a 5-inch refractor by Edward Emerson Barnard (1857 - 1923) in year of 1880. I have seen it in my 4-inch refractor as an elongated streak that was pinched in the middle. How about you? Lets not get so wraped up in apparent discrepancys.

#6 kcb

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Posted 05 July 2014 - 09:50 PM

the night sky observers guide,ngc6302 visual 9.6,bug nebula

#7 sgottlieb

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Posted 06 July 2014 - 04:37 PM

Although Barnard discovered NGC 6302 with his 5-inch refractor at Nashville (the discovery note is here), he also observed it with the 36-inch refractor at Lick and produced a pretty cool sketch. Now you can see why he nicknamed it the Bug Nebula!

#8 Scanning4Comets

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Posted 06 July 2014 - 06:20 PM

Megastar lists it as mag. 12.8 P.

There you go, another one. The point is, can you see it? If so, was it cool to look at? If so, log it and move on. That's what I've done, many times. The Bug is pretty cool.


Well, things like this are not that simple. You have magnitude, size, surface brightness and the fact that I am getting mixed magnitudes on different sites and programs, plus is is very low in altitude,

I tried for it last Friday night and couldn't see anything. I can't remember if I put in a Lumicon O-III filter or not, so I will try again next time with the filter.

Thanks you guys !!!! :grin:

CS!

#9 Feidb

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Posted 07 July 2014 - 02:34 PM

I've seen it with an 8-inch f/9.44 from an altitude of about 3500 feet or so in Spain back in 1983 or thereabouts. I was looking over a store complex with a few street lights.

It depends on the night.

#10 Galaxy_Mike

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Posted 12 July 2014 - 08:57 PM

If you're wondering if you can see it or not, you might take a look at Deep Sky Pedia and see what other observations have been made , and what aperture they used. Not 100%, but can give you an idea.

#11 Starman1

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Posted 14 July 2014 - 05:27 PM

It's obviously very blue:
B magnitude 7.1
V magnitude 9.6
P magnitude 12.8
despite the artificially-colored Hubble image.

It's in my list of 500 Best Dsos, and was easily visible in my 5" Maksutov.
My notes from that scope:
mod.brite,same size & mag as M76,streak w/brite end & dimmer end,diffuse edges,like aphid in side view,"The Bug"

It's also interesting how the appearance changes with magnification.
In the 12.5", at low power (under 150X), it appears like a bug with two body segments and some "legs" sticking out--easy to understand how it got the name "Bug Nebula".
Yet, at high powers (228-388X), it looks more like a bow-tie or butterfly (hence, the other name: "Butterfly Nebula") where the "ends" are very ragged.
It has a high surface brightness, so is easy if you can see that low and it's still several degrees above the horizon (I saw/see it at an altitude of 18-20 degrees when it crosses my meridian, depending on site).
I'm inclined to believe the V magnitude, because this one isn't faint at all.
and since my notes say "same brightness as M76", which has a V magnitude of 10.1, that's another indication the P magnitude doesn't correspond to what we see.

#12 beatlejuice

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Posted 14 July 2014 - 07:13 PM

It's going to be tough from here as it culminates at about 9.5 degrees. But we'll give it a try this weekend.
Heck, last year we got what was visible of the Northern Jewelbox (a misnomer for sure) at 4 degrees above the horizon.

Eric

#13 stevecoe

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Posted 15 July 2014 - 04:22 AM

Howdy all;

I love the Bug, lots of great detail.

Here is an observation from Australia with a 5" refractor, another from Arizona with my old Nexstar 11.

NGC 6302 5" f/8 QLD, Australia S=6 T=7 18mm pretty bright, small, elongated, not much at this aperture. 12" f/15 Cassegrain 18mm no filter pretty bright, pretty small, very much elongated 1.8X1 E-W. The central spot is not stellar, it is a bright spot about 3 arc seconds in size. The Bug Nebula has a high surface brightness.

NGC 6302 Nexstar 11 Arizona City Messier Marathon S=6, T=7 breeze has died off 22mm pretty faint, pretty small, bright middle, irregular figure, the bright middle is round, but not stellar, it is about 3 times the size of the seeing disk. The view of this object as a bipolar nebula is immediately obvious.

Here is a drawing with a 17.5 inch at 330X, no filter.



Steve Coe

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#14 blb

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Posted 15 July 2014 - 08:20 AM

Well, things like this are not that simple. You have magnitude, size, surface brightness and the fact that I am getting mixed magnitudes on different sites and programs, plus is is very low in altitude,

I tried for it last Friday night and couldn't see anything. I can't remember if I put in a Lumicon O-III filter or not, so I will try again next time with the filter.

Maybe they are. What magnification did you use when trying to find this small object? How did you try to find it? Did you use go-to or did you star hop to the object? If you star hoped to the object with a low power eyepiece, perhaps you did not see the small object in your field-of-view, or maybe your go-to just missed it.

It's obviously very blue:
B magnitude 7.1
V magnitude 9.6
P magnitude 12.8

The magnitudes that I have found match what Don has posted. The problem is often that many references list the photographic mag., the blue mag. or sometimes gives the visual mag. of the object without stating the which magnitude is given. I think magnitude should not be given unless how it was determined is stated because of the confusion it gives people like you. Any way magnitude is only a guide to how bright the object will appear in your telescope. I sometimes think that size is more important. Again I saw this nebula in my 4-inch TV102 refractor because Steve O'Meara had observed, described, and sketched this nebula using a 4-inch refractor in his book on the Caldwell objects. I knew that I could see it too if my sky was dark enough. So damm the magnitude! Still though this is a fairly bright nebula.

If you are trying to use magnitude for determining weather or not you can see this object, well then you need to determin which magnitude is given. I seldom use magnitude like this except where I have already determined the limit for the type of object I am viewing.

#15 Galaxy_Mike

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Posted 16 July 2014 - 11:57 AM

I think I got this last night in 20x80's. Conditions were excellent, which you kind of need with objects lower in the sky. I was able to get it in 4.5" even after the moon came up, though the moon was blocked by clouds at least somewhat.

It was non stellar at 36x if you looked close, perhaps the best view was 90x. I didn't try 60x.

The filter helped at 36x more than 90x.

The False Comet Complex is nearby, and visible in 20x80's

Beatlejuice I like to see low objects at times, but they aren't in their full glory that low.

#16 Starman1

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Posted 16 July 2014 - 01:07 PM

For those not familiar with this great binoculars viewing area, the "False Comet" to which Mike refers is a group of star clusters in Scorpius roughly in the Zeta Scorpii area that is composed of NGC6231, Cr316, Cr318, VdB-Ha202, VdB-Ha205 and the nebula IC4628.
It's one of the finest binoculars areas of the entire sky for those of you for whom the group culminates high enough off the horizon.

#17 blb

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Posted 16 July 2014 - 03:39 PM

I agree with you Don. The "False Comet" is an incredible binocular object from a dark sky site. This grouping of clusters, etc., is a wonderful object to view even in my 10x50 binoculars and yet it is seldom mentioned. Each cluster which makes up this object, including Tr24, is also a great telescopic target too. Although, as of yet, I have not seen the nebula IC4628, due to it's low elevation I suspect. All this is only about four degrees from the Bug Nebula too. :bigshock:

#18 Scanning4Comets

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Posted 17 July 2014 - 02:53 PM

It's obviously very blue:
B magnitude 7.1
V magnitude 9.6
P magnitude 12.8
despite the artificially-colored Hubble image.

It's in my list of 500 Best Dsos, and was easily visible in my 5" Maksutov.
My notes from that scope:
mod.brite,same size & mag as M76,streak w/brite end & dimmer end,diffuse edges,like aphid in side view,"The Bug"

It's also interesting how the appearance changes with magnification.
In the 12.5", at low power (under 150X), it appears like a bug with two body segments and some "legs" sticking out--easy to understand how it got the name "Bug Nebula".
Yet, at high powers (228-388X), it looks more like a bow-tie or butterfly (hence, the other name: "Butterfly Nebula") where the "ends" are very ragged.
It has a high surface brightness, so is easy if you can see that low and it's still several degrees above the horizon (I saw/see it at an altitude of 18-20 degrees when it crosses my meridian, depending on site).
I'm inclined to believe the V magnitude, because this one isn't faint at all.
and since my notes say "same brightness as M76", which has a V magnitude of 10.1, that's another indication the P magnitude doesn't correspond to what we see.

--------------------
Don Pensack


Thanks Don!

#19 Scanning4Comets

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Posted 17 July 2014 - 03:00 PM

Maybe they are. What magnification did you use when trying to find this small object? How did you try to find it? Did you use go-to or did you star hop to the object? If you star hoped to the object with a low power eyepiece, perhaps you did not see the small object in your field-of-view, or maybe your go-to just missed it.


I star hopped and used a map I drew up myself. I used a low power EP to search the area. This time, I will use a higher power EP. Here is my map I have made inverted to see more clearly. I just checked my starfield with Stellarium, and my map that I drew up doesn't have enough faint field stars to hop to the EXACT area, so I will need to draw up a new map with fainter field stars to hop from.

Maybe i can get one of the guys I observe with to get his GOTO scope on it tonight....No time to draw a map up!

Thanks for the info Buddy! :)

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#20 stevecoe

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Posted 17 July 2014 - 11:42 PM

Here is a shot with a 135mm lens and 6 minutes exposure.

Steve Coe

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#21 Scanning4Comets

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Posted 18 July 2014 - 02:25 PM

Where is it?






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