15P/Finlay
| Discovery | |
|---|---|
| Discovered by | William Henry Finlay |
| Discovery date | September 26, 1886 |
| Alternative designations |
1886 S1; 1886 VII; 1886e; 1893 K1; 1893 III; 1893a; 1906 V; 1906d; 1919 II; 1919d; 1926 V; 1926d; 1953 VII; 1953i; 1960 VIII; 1960d; 1967 IX; 1967g; 1974 X; 1974d; 1981 XII; 1981e; 1988 IX; 1988f |
| Orbital characteristics A | |
| Epoch | 2014-Dec-09 (JD 2457000.5) |
| Aphelion | 6.019 AU |
| Perihelion | 0.976 AU |
| Semi-major axis | 3.488 AU |
| Eccentricity | 0.7202 |
| Orbital period | 6.51 a |
| Inclination | 6.799° |
| Dimensions | 1.8 km (uncertain)[4] |
| Last perihelion | December 27, 2014[1][2][3] June 22, 2008 |
| Next perihelion | July 13, 2021[1] |
| Perihelion distance at different epochs[1] |
|||||||
| Epoch | Perihelion (AU) |
||||||
|---|---|---|---|---|---|---|---|
| 1866 | 1.0 | ||||||
| 1906 | 0.96 | ||||||
| 1919 | 1.0 | ||||||
| 1981 | 1.1 | ||||||
| 2008 | 0.97 | ||||||
| 2021 | 0.99 | ||||||
Comet Finlay is a periodic comet in the solar system discovered by William Henry Finlay (Royal Observatory, Cape of Good Hope, South Africa) on September 26, 1886. It came to perihelion (closest approach to the Sun) on December 27, 2014,[2] at around apparent magnitude 10.[5]
When the first parabolic orbit calculations were made in 1886, there was a similarity between this orbit and that of Francesco de Vico's lost periodic comet of 1844 (54P/de Vico-Swift-NEAT). Lewis Boss (Dudley Observatory, Schenectady, USA) noted large discrepancies between the orbits and after further observations concluded that de Vico's comet could not be the same as Finlay's.[6]
The 1899 apparition was missed, in 1910 a close pass with Jupiter increased the orbital period, in 1919 the path was off predictions and a new comet discovered by Sasaki (Kyoto Observatory, Japan) on October 25, 1919, was discovered to be Finlay's.
The magnitude of the comet declined after 1926, and it was not until 1953 that it has been observed on every return.
During the 2015 perihelion passage the comet outburst on 16 December 2014 from magnitude 11 to magnitude 9 becoming bright enough to be seen in common binoculars with a 50 mm objective lens.[7] On December 23, 2014, 15P and Mars were only 1/6 of a degree apart in the sky after sunset.[7] But by December 23, 2014, the comet had dimmed considerably since the outburst. On 16 January 2015, the comet outburst to magnitude 8.[8]
The comet currently has an Earth-MOID of 0.01 AU (1,500,000 km; 930,000 mi).[9] On October 25, 2060, the comet will pass roughly 0.04 AU (6,000,000 km; 3,700,000 mi) from the Earth.[9]
References
- ↑ 1.0 1.1 1.2 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 2.0 2.1 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Comet II (2004) pg 242
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 7.0 7.1 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 9.0 9.1 Lua error in package.lua at line 80: module 'strict' not found.
External links
- Orbital simulation from JPL (Java) / Horizons Ephemeris
- Elements and Ephemeris for 15P/Finlay – Minor Planet Center
- 15P at Kronk's Cometography
- 15P at Kazuo Kinoshita's Comets
- 15P at Seiichi Yoshida's Comet Catalog
- 15P at CometBase database
- 2014 June 22 recovery at apmag 20 (comets-ml)
- 15P/Finlay on 18 Dec 2014 (200mm lens F5.6 / Rob Kaufman of Australia)
- Animation of 15P/Finlay by FRAM (0.3-m f/10 reflector + CCD, MPC I47), 17th and 18th Dec 2014 (Martin Masek)
| Periodic comets (by number) | ||
|---|---|---|
| Previous 14P/Wolf |
15P/Finlay | Next 16P/Brooks |
