Comet Dodwell–Forbes, formally designated as C/1932 Y1, is a long-period comet discovered independently by Alexander F. I. Forbes and George F. Dodwell in late 1932. It was Dodwell's only comet discovery, while it was Forbes's third overall.
Discovery[1] | |
---|---|
Discovered by | George F. Dodwell Alexander F. I. Forbes |
Discovery site | Adelaide, Australia Cape Colony, South Africa |
Discovery date | 15–17 December 1932 |
Designations | |
1932n[2] 1932 X | |
Orbital characteristics[3] | |
Epoch | 20 January 1933 (JD 2427092.5) |
Observation arc | 63 days |
Number of observations | 23 |
Aphelion | 80 AU |
Perihelion | 1.131 AU |
Semi-major axis | 40.6 AU |
Eccentricity | 0.97216 |
Orbital period | 259 years |
Max. orbital speed | 39.3 km/s |
Inclination | 24.502° |
78.589° | |
Argument of periapsis | 327.357° |
Last perihelion | 30 December 1932 |
Next perihelion | ~2191 |
TJupiter | 1.320 |
Earth MOID | 0.2040 AU |
Jupiter MOID | 0.7849 AU |
Physical characteristics | |
Comet total magnitude (M1) | 9.1 |
8.0 (1933 apparition) |
Discovery and observations
editThe comet was the brightest of thirteen comets observed in 1932, when George F. Dodwell reported his discovery on 17 December 1932. However, it was soon realized that Alexander F. I. Forbes first spotted the comet from his 8 in (20 cm) reflector two days earlier.[1] The comet was a 10th-magnitude object at the time of its discovery.[4]
In 1949, it was speculated that comet Dodwell–Forbes and eight known others were members of a "Neptune-family" of comets based on their similar aphelia (85 AU) and orbital periods ranging between 235 and 300 years.[5] However, it is now concluded that this comet family did not exist, and their apparent association with Neptune were a result of orbital resonances with Jupiter.[6]
References
edit- ^ a b G. van Biesbroeck (1933). "Comet Notes". Popular Astronomy. 41: 116–117. Bibcode:1933PA.....41..116V.
- ^ "Comet Names and Designations". International Comet Quarterly. Retrieved 11 December 2024.
- ^ "C/1932 Y1 (Dodwell–Forbes) – JPL Small-Body Database Browser". ssd.jpl.nasa.gov. Jet Propulsion Laboratory. Retrieved 11 December 2024.
- ^ C. D. Crommelin (1933). "Comets" (PDF). Monthly Notices of the Royal Astronomical Society. 93 (4): 272–275. doi:10.1093/mnras/93.4.272.
- ^ C. H. Schütte (1949). "Two New Families of Comets". Popular Astronomy. 57: 176–182. Bibcode:1949PA.....57..176S.
- ^ "Comet families". Oxford Reference. Oxford University Press. Retrieved 11 December 2024.
External links
edit- C/1932 Y1 at the JPL Small-Body Database