Celestial hemisphere:  Northern  ·  Constellation: Ursa Minor (UMi)  ·  Contains:  NGC 6217
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NGC 6217 - Arp 185 in Ursa Minor., astroeyes
NGC 6217 - Arp 185 in Ursa Minor.
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NGC 6217 - Arp 185 in Ursa Minor.

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NGC 6217 - Arp 185 in Ursa Minor., astroeyes
NGC 6217 - Arp 185 in Ursa Minor.
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NGC 6217 - Arp 185 in Ursa Minor.

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My image of Arp 185, NGC 6217 in Ursa Minor, taken in November 2010. 60 X 120 sec guided images., 10" f4.8 reflector/H9C ccd camera.

NGC 6217 was long ago observed to be an active galaxy. No. 185 in Arp's catalogue, it had been put into the 'narrow filaments' category from optical inspection. Forty years later it turns out to have an X-ray jet at almost a right angle to the suspected optical ejection. Serendipitously there is a white dwarf located quite close to NGC 6217 which attracted many X-ray exposures of the field. X-ray jets of this strength are rather rare and serve to emphasize the unusually active nature of NGC 6217.

The most extraordinary feature of NGC 6217, however, is that it is surrounded by quasars . Two of these are aligned longitudinally across the active galaxy within 4°, and the redshifts of the two are z = 0.376 and 0.380. The probability of finding by accident two sources this bright, this close to any given point in the sky is about 6 × 10-3.

A third quasar falls only within 27° of this alignment and has z = 0.358, not as conclusive as the well aligned pair but certainly adding to the significance of the association. There are several other quasars at various orientations to NGC 6217 as can be seen in image C, the Simbad map of the area.

The P.A. of the z = 0.376 quasar is 109° from NGC 6217. This is in the direction of Hickson compact group 84 (P.A. = 117) and in the general direction of the cluster A2248, which have redshifts z = 0.056 and 0.066, respectively. Arp suggested that there is one ejection line along the paired quasars to A2248 and one along the X-ray jet from NGC 6217 to the clusters A2181 and A2256.

Arp 185 is an interesting galaxy. Not immediately obvious but just barely visible in my image, are the faint outer spiral arms/ring. The galaxy is classified SB(r)bc (inner ringed spiral) and is mag. 12 with a s.b of 14 mag/square arcmin.

I find Arp's arguments very interesting. His reasoning may, or may not be flawed but there can be no doubting his determination to make his views known in the face of overwhelming and almost total opposition.

Many thanks for looking.

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    NGC 6217 - Arp 185 in Ursa Minor., astroeyes
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NGC 6217 - Arp 185 in Ursa Minor., astroeyes