C/1935 A1 (Johnson)
Comet Johnson photographed by George van Biesbroeck shortly after perihelion on 27 February 1935[1] | |
| Discovery[2] | |
|---|---|
| Discovered by | Ernest Leonard Johnson |
| Discovery site | Union Observatory |
| Discovery date | 7 January 1935 |
| Designations | |
| 1935a[3] 1935 I | |
| Orbital characteristics[4] | |
| Epoch | 28 February 1935 (JD 2427861.5) |
| Observation arc | 68 days |
| Number of observations | 34 |
| Aphelion | ~190 AU |
| Perihelion | 0.811 AU |
| Semi-major axis | 93.21 AU |
| Eccentricity | 0.99130 |
| Orbital period | ~900 years |
| Inclination | 65.424° |
| 92.445° | |
| Argument of periapsis | 18.399° |
| Mean anomaly | 0.002° |
| Last perihelion | 26 February 1935 |
| Next perihelion | ~2830s |
| TJupiter | 0.519 |
| Earth MOID | 0.149 AU |
| Jupiter MOID | 2.175 AU |
| Physical characteristics[5] | |
| Comet total magnitude (M1) | 9.5 |
| Comet nuclear magnitude (M2) | 12.5 |
| 8.4 (1935 apparition) | |
Johnson's Comet, formally designated as C/1935 A1, is a long-period comet with a 900-year orbit around the Sun. It is the first of four comets discovered by South African astronomer, Ernest Leonard Johnson.
Orbit
Between February and March 1936, Allan D. Maxwell calculated that the comet had an orbital period of 750 years, later revised to 896 years.[6][7] This is a follow-up to the preliminary parabolic solutions that were first calculated by J. P. Möller and H. Q. Rassumen a year prior.[5]
References
- ^ G. van Biesbroeck (1935). "Comet Notes". Popular Astronomy. 43: 254–255. Bibcode:1935PA.....43..254V.
- ^ "First Comet of 1935" (PDF). Nature. 135: 115. 1935. doi:10.1038/135115c0.
- ^ "Comet Names and Designations". International Comet Quarterly. Retrieved 27 January 2025.
- ^ "C/1935 A1 (Johnson) – JPL Small-Body Database Lookup". ssd.jpl.nasa.gov. Jet Propulsion Laboratory. Retrieved 27 January 2025.
- ^ a b G. W. Kronk (2009). Cometography: A Catalog of Comets. Vol. 4: 1933–1959. Cambridge University Press. pp. 20–25. ISBN 978-0-521-58507-1.
- ^ A. D. Maxwell (1936). "The Orbit of Comet 1935a". Astronomical Journal. 45 (1041): 49–54. Bibcode:1936AJ.....45...49M. doi:10.1086/105322.
- ^ A. D. Maxwell (1937). "Elements and Ephemeris of Comet 1935a (Johnson)". Publications of the Observatory of the University of Michigan. 6 (7): 63–65. Bibcode:1937POMic...6...63M.
External links
- C/1935 A1 at the JPL Small-Body Database