Comet 38/P Stephan–Oterma on 9.12.2018

  Size: 1800 px      
© Velimir Popov & Emil Ivanov 2018

38P/Stephan–Oterma is a periodic comet in the Solar System. It is a Halley-type comet (the period is between 20 and 200 years), with a period of 38 years. The discovery of this comet had a strange story. First the comet was discovered by Jérôme Eugène Coggia on January 22nd 1867 from the Marseilles Observatory, who thought he had found an unclassified nebula. Due to bad weather conditions he could not continue the observations that were taken by Édouard Stephan two days later. Stephan noticed that the object had moved and communicated the discovery. Since he did not mention the name Coggia in the telegram, his name was assigned to the comet. Also worthy of note is the independent discovery of Ernst Tempel, who identified the comet on January 28 near the star π Arietis. Ludwig Becker calculated a definitive orbit in 1891 and predicted its return between 1902 and 1912. The comet, however, was not observed. It was rediscovered by Liisi Oterma on November 6, 1942. Fred L. Whipple calculated an orbit and proposed identification with Comet Stephan of 1867. This information allowed to estimate the orbital period between 38.84 and 38.88 years. The subsequent appearance was successfully predicted by D. K. Yeomans. The comet was recovered on June 13, 1980 by H.-E. Schuster of the European Southern Observatory. 38P/Stephan–Oterma next comes to perihelion on November 10, 2018. It was rediscovered by Pan-STARRS on June 24, 2017 while at 5.3 AU from the Sun. This image was taken on the night of December 9th at 00:30 UT.

Image details:


Center of field RA 08:20:05 (h:m:s)
Center of field DE +32:11:10 (deg:m:s)
Size 1.87 x 1.25 (deg)
Pixel scale: 2.99 (arcsec/pixel)
Orientation: Up is 246 degrees E of N
Charts and image details obtained from
Optic(s): ASA 12" Astrograph @ f/3.6 (Newton)
Mount: ASA DDM85 Standard
Camera: SBIG STL 11000 M
Filters: Luminance, Red, Green, Blue, Astronomik filters
Dates/Times: 9.Dec.2018
Location: IRIDA Observatory, BG, longitude: E 24 44' 18", latitude: N 41 41' 42"
Exp. Details: L:2x3 min,R:2x3 min, G:2x3 min, B:2x3 min, Bin 2, Total Exposure Time - 24 min.
More details: Dark and flat frames reduction
Processing: PixInsight / PS
Copyright: Velimir Popov and Emil Ivanov 2013 - 2018. All Rights Reserved
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