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MarsG76

Observation Notes - 6 December 2015: Hunt for the Horsehead, 47Toucana, Orion and Carina Nebulae

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6th December 2015

Equipment: NexStar 8SE

Time: 01:00 - 03:45

During the imaging of Barnard33 through the OIII filter using the 80mm refractor, I setup the 8SE on the single arm alt-az mount for observing.

Orion Nebula looked great and bright through just the eyepiece but when using the UHC filter it was detailed and awesome. The shape of the nebula was clearly visible, the fishes mouth and the mustache shaped extends were very distinctly brighter than the reminder of the nebula. There was a lot of the nebulosity visible starting to take on the shape of the "flame" as photographed except it was more rounded.

The four stars in the trapezium were bright and distinct.

The second object I was looking for to observe was the globular cluster 47Toucana. When I located, it was not in the database of the NexStar 8SE hand controller (atleast not as 47Toucana), it looked dimmer that I was expecting. I spend a bit of time looking at the globular through both the 40mm eye piece and the 11mm Nagler... Both showed a dim image of the globular. Through the 11mm I did see some granulation and irregularly speckled stars extending out from the core.

I did a "identify object" scan on the hand controller and it come up as NGC362 and the next nearest object was NGC265 in the list.

Looking up the objects NGC362 is magnitude 8 and 47Toucana NGC104 is magnitude 5.8. Both of these objects should be a lot brighter in the eyepiece than the object I was observing and struggling, just barely resolving stars around the globular.

That point brings me to the next nearest object, NGC265. In StarWalk it's shown to be magnitude 12.5 and when squinting and de focussing my vision on the shown picture it definitely resembles the shape, brighter/denser core and speckled stars at the outer edges. It also makes a lot more sense for it to be so dim in the FOV when looking at it through a telescope with a maximum resolving power of magnitude 14.5.

So I think I was actually looking at NGC265, and not 47Tucana or NGC362. The reason why the catalog on the NS8 hand controller shown NGC362 as a first choice if because the object was manually found after locating the constellation Toucana, the three objects are close together, the NS8 has very little objects in this part of the sky in the database and the star alignment might have been a few degrees off.

The reason I didn't look up the data and thought the NGC362 was the Globular cluster 47Toucana is because I didn't want to turn on the iPhone or the iPad and destroy my night adapted vision...REMINDER: GET RED FILM FOR IPHONE AND IPAD.

47Toucana needs to be looked for and observed another night.... So does NGC362 for that matter and compare to NGC265 to confirm the above theory.

The next object I wanted to find and observe for the first time was the Horsehead nebula. Reading others observation about the Horsehead, some claim to have spotted it in 4" refractors from dark skies, I though that I might have a chance from my semi dark location.

I located Alnitak and looked for any hint of the Horsehead or Flame nebulae with no luck, than I spend a few minutes looking for the nebulae using UHC and OIII filters with no luck. I rushed a bit using the UHC and OIII since it's commonly documented that a h-beta filter is the best filter to spot it.

Through the h-beta filter Alnitak was still quite bright but the background was a lot darker, but I still couldn't spot either the Flame or the Horsehead nebulae. I've spend a fair bit of time looking for it through both the 40mm and 11mm eyepieces but at the end before I gave up I still couldn't spot any of them. When I brought my head up and looked at the sky toward Orion's Belt, it was quite obvious that my sight was quite dark adapted since the sky was glowing, it was almost milky bright... I put not seeing the Horsehead nebula down to the sky glow being much too bright for it to come through. The hunt will need to continue another night.

The last object I observed was The Carina Nebula. As previously the Carina nebula is a sight to behold, it is definitely my favorite nebula to observe along with the Orion Nebula.

It looks stunning through the UHC filter and 11mm eyepiece, the detail in the brightest arm was visible clearly, although not as defined as the last time I looked at it, but close.

Through the 40mm eyepiece and the f6.3 focal reducer, there was a lot of the nebula visible in the FOV. Not only the brightest arm, but also the other two features that starts to make the "storm trooper face" shape. This is another object that I always spend a considerable time observing through various magnifications.

Both the Orion and Carina nebulae have a slight blue-gray color look to them through the UHC filter which gives it a almost painted appearance.

Tonight I was not going to get stopped by dew like last time I was observing so I ran a RCA loom from the CGEM and through a gender changer connected the 8SE dew heater strap, seems to have done the trick since there was no dewing of the optics.

The seeing was quite still tonight but as dark adaption revealed, the sky glow was quite bright. Toward the end of the observing session some thin cloud patches were coming and going, not interfering with the imaging.

Tonight was definitely a great night of observing.

MG

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Very nice report. I enjoyed the read. 47Tuc is bright and large as Michael says, so should come up well I your scope. The HH is another matter. I have only seen it once from very dark skies when the transparency and seeing were excellent.

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Thanks for the comments gents... I definitely missed the mark when it comes to wanting to see 47Tuc, by a factor of about 7 magnitudes... Now I'm really hanging for a dark clear sky now....

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