![]() ![]() Once thought to be part of the Local Group, they are now known to belong to their own group- the IC 342/Maffei Group. The galaxies Maffei 1 and Maffei 2 are both nearby the nebula, although light extinction from the Milky Way makes them very hard to see. Small emission nebula IC 1871 is present just left of the top of the head, and small emission nebulae 670 and 669 are just below the lower back area. The object is more commonly called by the cluster designation IC 1848. Several small open clusters are embedded in the nebula: CR 34, 632, and 634 (in the head) and IC 1848 (in the body). Retrieved 27 November 2020.Westerhout 5 ( Sharpless 2-199, LBN 667, Soul Nebula) is an emission nebula located in Cassiopeia. Revista Mexicana de Astronomia y Astrofisica Conference Series. "Point-Symmetry and the Double Planetary Nebula KjPn 8". "Jets and the Shaping of the Giant Bipolar Envelope of the Planetary Nebula KjPn 8". "The discovery of a bipolar, rotating, episodic jet (BRET) in the planetary nebula KjPn 8". "Hamburg Schmidt-camera survey of faint planetary nebulae. "High-Resolution CO Imaging of the Molecular Disk around the Jets in KjPn 8". ![]() Bachiller, Rafael Cox, Pierre (March 1998). ^ a b c Forveille, Thierry Huggins, Patrick J.: CS1 maint: DOI inactive as of February 2023 ( link) Monthly Notices of the Royal Astronomical Society. "The proper motion distance to the remarkable bipolar planetary nebula KjPn 8". ^ a b Results for PN KjPn 8, SIMBAD, Centre de données astronomiques de Strasbourg, 27 November 2020."The expansion proper motions of the extraordinary giant lobes of the planetary nebula KjPn 8 revisited". Hubble Space Telescope observations suggest that KjPn 8 might be a very rare object, formed by a binary system in which both stars had similar masses, which reached the end of the Asymptotic Giant Branch phase within 10 to 20 thousand years of each other, and entered the planetary nebula formation stage nearly simultaneously. The central star has begun to ionize the central region of this disk. The disk is aligned with the youngest and fastest bipolar jet, which has an expansion velocity of about 300 km/sec. Microwave emission from carbon monoxide reveals the presence of a dense disk of molecular gas 30 arcseconds in diameter expanding at about 7 km/sec, with a mass ≥ 0.03 M ⊙. Combining this proper motion with an expansion velocity derived from spectral line profile widths allowed Meaburn to derive a distance to the nebula of 1600☒30 parsecs, and a kinematic age of 3400☓00 years. In 1997 John Meaburn compared images of the nebula taken in 1954 (as part of the Palomar Sky Survey) and 1991.He measured a proper motion of 34☓ milliarcseconds per year for two knots in the nebula. The envelope of KjPn 8 is expanding rapidly enough to allow the proper motion of features in the nebula to be measured. The physical size of this extended nebula is approximately 4.1 by 1.2 parsecs, much larger than a typical planetary nebula, while the core nebula known prior to 1995 is only about 0.2 parsecs in diameter. Narrow band images centered at Hα and forbidden line transitions of nitrogen, sulphur, and oxygen reveal pairs of bow shocks at differing position angles, indicating the presence of episodic ejection of material along a precessing jet, similar to what is seen in Fleming 1, but much larger (in angular extent). This is the largest known bipolar structure associated with a planetary nebula. Very little was published about this nebula until 1995, when it was realized that KjPn 8 sits in the center of a very large filamentary nebula, 14 by 4 arc minutes in size. Parsamyan in 1971 and independently by Luboš Kohoutek in 1972. KjPn 8 is a bipolar planetary nebula which was discovered by M.A. The upper image shows Hα emission, and the lower image shows (ionized Nitrogen) emission. Two mosaic images of KjPn 8 made with the Aristarchos 2.3 m Telescope. ![]()
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