April 23, 2006 Instrument: 18-inch Obsession |
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Fragment B - RA: 15h 18.3m / DEC: +29° 48'.6 |
With recent reports that Fragment B's nucleus had broken up into two main components, I decided to observe this fragment at high magnification to explore the coma and pseudonucleus. My sketch presents a 399X view in the 18-inch Obsession. Fragment B's head is just north of center. A 14th magnitude GSC star lies about 1' to the southeast. A second star of similar brightness simmers 1'.4 to the east-northeast. The third star in the field is another 14th magnitude ember and is stationed 2'.7 south of the comet fragment. It's a gusty night but, during the occasional calm, a stellar pseudonucleus emerges at the very tip of the head. A second but fainter stellaring pops in and out intermittently. This pseudonucleus lags about 14" behind (south) of the first. It's shrouded within a 30" tear-shaped coma and a small gap separating the two pseudonuclei is consistently visible. A slender tail extends south and west along the fragment's spine over a distance of about 3'. This is flanked to the east by an arcing, feathery tail which extends well beyond the field boundary. A more subtle feathery tail angles south and west from the fragment's head. |
Fragment C - RA: 15h 44.0m / DEC: +28° 05'.0 |
While observing Fragment C the night of April 18, I noted three stellarings within the coma. A review of professional and amateur images of this fragment made that night and since has failed to produce any evidence suggesting pronounced fragmentation of the nucleus. Tonight's 399X view in the Obsession is captured in the sketch at left. The head lies about 30" northeast of a 13th magnitude GSC star. A 15.6 (B) magnitude star lies 2'.5 to the northwest and just inside the field boundary. About 3'.6 to the southeast of the pseudonucleus, stands a 15.3 (B) magnitude star. Fragment C's pseudonucleus features a stellar core enmeshed within a bright inner coma. This coma is tiny, perhaps 15" by 10" in size and tear-shaped. The brightest portion of the tail sweeps southwest from the head, broadening and arcing further west a the field boundary. Similar to Fragment B, this fragment features a narrow, bright spine trailing behind the coma for a distance of several arcminutes. |
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Revised: April 30, 2006 [WDF]