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*****  A SUSPECTED NEW PLANETARY NEBULA DISCOVERED  *****

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A suspected new planetary nebula has been discovered by Matthias Kronenberger on the DSS prints. The best position seems to be 2 12 27.86 +47 27 10.1 (J2000) with a size of 1.0 x 1.5’. The nebula appears as two lobes of nebulosity aligned roughly N-S on the blue image, which are fainter on the red image and invisible on the infrared image. The blue central star is obvious when comparing the blue and red images. The nebula is marginally recorded as a 25-micron-only IRAS faint-source 'reject', IRAS Z02091+4712. This object was previously catalogued as a galaxy and is listed as the galaxy ZOAG G136.85-13.22 in SIMBAD and the galaxy HFLLZOA E135 in NED. The discovery note is reproduced below along with the first visual observation.

In the course of an ongoing survey of the DSS for unknown PNe and clusters I came across a new and comparably bright planetary nebula candidate that does not seem to be catalogued in any of the 'classic' resources (Strasbourg/ESO, Kohoutek, VIZIER, SIMBAD, MASH/IPHAS etc.). The coordinates of the candidate, (J2000) 02 12 27.9 +47 27 10, place it in NE Andromeda, about 15' W of the double star Struve 228; its size is approximately 1.0' x 0.5'. An interesting and unusual feature of the PN candidate is its pronounced bipolarity; this bipolarity may also be the reason why the candidate was overlooked by previous surveys despite its relatively high brightness. In fact, the candidate does not look much different from an interacting pair of galaxies on the blue and red DSS plates and has been catalogued as such previously. However, unlike galaxies, the object disappears completely on the DSS-IR plate (generally a sign for a line emitter), and exhibits a very blue stellar source in its geometric center.

Last Thursday, Uwe Glahn, Ronald Stoyan and myself made an attempt to observe the object visually. The observation took place at the Bielerhoehe in the Silvretta mountain ridge in western Austria (altitude: 2.000 m). Skies were brilliant, with SQM readings up to 21.70. After an unsuccessful attempt with my 15", we tried the PN candidate with Uwe's superb new 27-inch Dobson (see http://www.deepsky-visuell.de/ATM/27_Newton/Bau.htm for details - in German !). With OIII filter, a faint, 2:1 elongated glow was visible just N of the tip of a short, SW-NE running chain of stars mag 13 and fainter. The best view of the PN candidate was at 419x where both lobes of the PN candidate could be seen; while the N lobe appeared as a faint but distinct roundish glow about 30" NW of a 15 mag star, the S lobe was less distinct and did not exhibit more than a very faint, ill-defined haze.

A sketch of the object based on this observation can be found here: http://www.deepsky-visuell.de/Zeichnungen/Kn.htm The preliminary ID of the object is Kn J0212.4+4727.

DOUBLE STAR DRAWINGS IN LEO - Courtesy of Jeremy Perez

Leo Doubles - Sketches Courtesy of Jeremy Perez

Jeremy Perez from Flagstaff, Arizona (USA) has been kind enough to provide some excellent drawings of a selection of double stars in the constellation of Leo. His website 'The Belt of Venus' contains details regarding the tools and techniques used to create these drawings together with a wealth of other information related to his strong interest in astronomy.

Clicking on the image on the left will enable you to select the areas circled in red to view his individual double star drawings. Jeremy's website can be found here.

Exposure Details LRGB = 70:60:70:70 All binned 1x1 with Astrodon NIR filters. Red is assigned to a band peaking at about 850nm, Green peaking at about 830nm and Blue at 750nm. The luminance is "visible blocked" with zero response shorter than 700nm.

Description UKS1 was discovered on infrared plates taken by the 48" UK Schmidt telescope. It has the incredible visual magnitude of 17.3 but still has been glimpsed in very large Dobsonians. It has long been called the faintest globular in the milky way but recently discovered globulars in the 2MASS survey are even fainter. The following description is from the 2MASS image caption. This cluster, in the Galactic bulge and near the Galactic center (l=5.1°, b=0.8°), is quite reddened and in a very crowded stellar field. Ortolani, Bica, & Barbuy (1997, A&AS, 126, 319) present optical photometry of the cluster and find that the extinction is nearly 11 visual magnitudes, that the distance to the cluster is 7.4 kpc (24,124 light years), and that the cluster may be metal-rich. Near-infrared photometry was previously obtained for the stars in the cluster, along with those for 19 other bulge clusters, by Minniti, Olszewski, & Rieke (1995, AJ, 110, 1686).

Located close to the head of the Dragon, mu Dra (17 05 20.12 +54 28 12) is a long period binary system, first found by William Herschel in 1781. With a period of 672 years, the apparent separation of the two stars ranges from 2".0, which last occurred about 40 years ago, and 5".7. At the present time it is almost 2".4 apart at position angle 5°. With components of magnitudes 5.66 and 5.69 the star is easily visible to the naked-eye and is an excellent target for small telescopes so it is included in James Mullaney's One Hundred Showpiece Double and Multiple Star list, where he gives the colours as yellowish-white. Sissy Haas also notes the stars as goldish-white, but Smyth sees them only as white. There is evidence for a spectroscopic companion to B which may be bright and wide enough to be resolvable in the optical, and there is a mag 13.7 star at 12" may also be part of the group. The system lies at a distance of 90 light years.

Nu Scorpii (16 11 59.27 -19 06 53) is the southern equivalent of the Double-Double in Lyra, although the brighter pair is more difficult to divide than its northern equivalent, and as a consequence at least 150-mm is needed to see the four components clearly. The wide pair catalogued by Herschel as H V 6 consists of white stars of magnitude 4.2 and 6.0 separated by 41". In 1846 Mitchel, using an 11-inch refractor in Cincinnati, resolved the companion into two stars about 1".3 apart. Burnham then discovered that the primary was also double with his 6-inch Clark in 1873 when the separation was around 0".6. Since that time both pairs have slowly widened and the current values are 1°, 1".3 for A and 55°, 2".3 for B. This is a physical system of high multiplicity since A is double again at the sub-0".1 level and there is also a spectroscopic component of 5.5 day period. The writer has measured both bright pairs from the UK with 20-cm but it needs a night with very steady air to do this.

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