Today I want to pass the brighter nebulas within the milky way and leave the galactic latitudes to continue the galaxy dance of the always to short spring. The destination will be the nice galaxy pair NGC 7102 / PGC 214783 on the level of Messier 15 but 6° south.
The history is as often interesting. First discovered by the German astronomer Albert Marth in 1863 on Malta. As an assistant of William Lassell, he uses the famous and powerful 48" reflector with a speculum mirror and profited from the good skies. He describes the object as "faint, pretty large, round". Some years later in 1894 the French astronomer Guillaume Bigourdan discovered the same object with the 12.4" refractor at Paris observatory. He describes the galaxy as "extremely faint, pretty large, several extremely faint stars and nebulosity". He knows about the NGC designation but made a fault in the coordinates by using different offset stars and so measured the same galaxy twice. Both missed the PGC companion.
From the astrophysical aspect both galaxies seems to interact. NED gives distances of around 200 million light-years. Beside a recorded supernova in 2003 I could not find any scientific papers about the pair. Interestingly the fainter PGC also has a 2MFGC designation which stands for "2MASS Flat Galaxy Catalog".
In the telescope the main NGC is just visible in very small apertures. The PGC companion suggest a minimum aperture of around 16-inch. I recorded a "direct vision" and a "relative high surface brightness" in the 27-inch. Larger telescopes shows also a hint of the faint spiral structure of NGC 7102.
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