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Old 30-03-2015, 01:00 AM
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kinetic (Steve)
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Planetary PK294-01 mono

I got a set tonight of this little planetary neb nearby IC2944
A diffraction spike or reflection from a nearby star just out of fOV
cuts almost through the scene of the action! :/

Some observing notes from Sir John Herschel:

John Herschel (1847) Cape Observations

This planetary nebula was discovered by Sir John Herschel at the Cape of Good Hope with an 18-inch f/13 speculum telescope. He recorded it as "A perfect planetary disc 6 arcsec diameter; quite sharp, with not the least haziness. It is of a most decided independent blue colour when in the field by itself, and with no lamp light and no bright star. About 10' north of it is an orange coloured star 8th mag. When this is brought into view the blue colour of the planetary becomes intense. Shown to my attendant, John Stone, who, on being asked what colour, said at once 'blue.' " His next observation was recorded as "planetary nebula - in light to a star 7th mag; diam. in RA = 1.3 seconds; viewed with all the powers; very beautiful; decidedly blue." On the next occasion he described it as a "planetary nebula, colour a beautiful rich blue, between prussian blue and verditter green. The light is fully = that of a star 8th mag diameter; 2 seconds in RA; 12 arcsec by careful estimation. When kept steadily at rest its outline is sharp and clean, and perhaps a very little elliptic. A feeble lamp light gives it a deep indigo contrasted colour. Ditto if a red star N.p., about 10' distant, be brought into the field with it. My attendant saw it and declared proprio motu that the light has quite a green cast in it. About 90 stars are in the field, none above 11..12 mag, and only one of that magnitude (meaning when the neb. is central). It has none but stars 16th mag near it." Then, on 26 February 1835, after completing the sweep for the night, he viewed it with Maclear: "Blue colour very conspicuous. Has one small companion certain (pos by diagram about 290 ) dist = full diameter, another nearly certain (at about half the distance by diagram, and pos about 135 ) The field is full of stars. Total light of planetary = star of 6th magnitude or 6' m. A very little oval in position about 160 or 165." Some while later, he recorded it as "planetary, diameter 8..10 arcsec, perfectly round and well defined, and of a fine blue colour." His final observation was recorded as "Planetary nebula. Perfectly round, very planetary; colour fine blue; a very little ill defined at the edges; has no 'satellite stars'; very like Uranus, only about half as large again and blue. Diameter in RA = 1.5 seconds."

Steve
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Old 01-04-2015, 01:14 AM
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astronobob (Bob)
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Well done on that faint fuzzy Steve Inspiring also, yep, top show ! !
Im actually liking the few PNs on IIS recently, interesting targets hey
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Old 01-04-2015, 09:57 AM
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H.Treur
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Amazing.
It is hardly detectable photographically, let alone to detect it visually!
And what's more; to discòver it visually!... Like Herschell did.
An amazing accomplishment.
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