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[Re]Re: (IAAC) Obj: The Homunculus - Inst: 20




>Andrew Murrell schrieb:
>> ----
>>
>> Observer: Andrew Murrell
>> Your skills: Advanced (many years)
>> Date/time of observation:
>> Location of site: Ilford NSW Australia (Lat , Elev )
>> Site classification: Rural
>> Sky darkness: 6.5 <1-10 Scale (10 best)>
>> Seeing: 8-9.5 <1-10 Seeing Scale (10 best)>
>> Moon presence: None - moon not in sky
>> Instrument: 20" f5 Dobsonian
>> Magnification: 160-700
>> Filter(s): none
>> Object(s): The Homunculus
>> Category: Planetary nebula. Emission nebula.
>> Class: stellar ejecta
>> Constellation: carina
>> Data: mag 6.5 size 30"
>> Position: RA 10:45.1 DEC -59:41
>> Description:
>> The Homunculus is the small nebulae that surrounds Eta Carina. It is the
>> envelope
>> of stellar material that was ejected from the star about a century ago. This
>> is the
>> only nebulae that shows an obvious colour, Bright orange. This colour is very
>> striking against the star background. The initial observation was at 160x.
>> This shows
>> the surrounding keyhole nebulae NGC3372, which defies description. The
>> Homunculus
>> appears as a peanut shaped orange blob about 30" across. At 300x it appears
>> as a bright
>> hazy star with a lobe or bubble of material on either side, orietated SW-NE.
>> The lobe
>> to the SW is the brightest, and appears granular with a dark lane running
>> throughthe
>> middle which curls to the southat the end. The NE lobe is fainter and shows
>> no internal detail
>> The center star is about 6.5 magnitude and has a jet progecting to the north
>> about 5" long.
>> Averted vision at this power intensifies the colour and shows a bright knot
>> 5" WSW of the star
>> in the SW lobe. By increasing the magnifaction to 720x even more detail was
>> glimpsed. In moments
>> of perfect seeing the granulation in the NE lobe became apparent. The bright
>> knot became visible
>> with direct vision,and the colour remained. The dark lane seen before in the
>> SW lobe lost some of
>> its structure, looking more difuse and ending in a small dark hole positioned
>> about 5" from the southern
>> edge of the nebulae. The higher magnifaction increased the contrast. The edge
>> of the nebulae remained
>> sharp across the entire perimeter and the arm or jet was easily picked up.
>> What became most noticable
>> about the homunculus was the FAINT halo that surrounded the entire object and
>> doubled its size.
>> The difuse glow had an indistinct edge and appeared evenly distributed about
>> the object. No intermal
>> details were seen in this faint envelope
>> A right angle of 15th magnitude stars are positioned about 15" NW of the
>> central star adding to the
>> view at this power. As a side note to this observation stars of 4th magnitude
>> and brighter had difraction
>> rings visible, one complete ring and two partial. The seeing was the best in
>> several years that I had seen
>> Reducing the magnifaction to 300x I looked for the faint halo but it would
>> not reveal itself, probably due
>> to the glare from the star and the nebulae.
>> This goes down as one of the TOP 5 objects in the entire sky.
>> --
>> Optional related URLs:
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>> http://www.tiac.net/users/lewkaren/netastrocatalog/enter-log.html
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>+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>Hi Andrew!
>
>Very nice observation report. I will never see such objects with my 20incher here
>from Germany...
>
>With kind regards from Germany, Jens
>
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>
Hi sir! andrew
Wonderful and shocking
your observation is amazing, espacially your own 20" dob and description.
I have 6" newtonian hand-maded, so sight not good well.
I'm South of Korean, then have beautiful dark sky.
........
Good luck!!!
with Je seop Park
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