15P/Finlay

From Wikipedia, the free encyclopedia
Jump to: navigation, search
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 in fact 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 seen in common binoculars with a 50mm objective lens.[7] On 23 December 2014, 15P and Mars were only 1/6th of a degree apart in the sky after sunset.[7] But by 23 December 2014 the comet had dimmed considerably since the outburst. On 16 January 2015, the comet outburst to magnitude 8.[8]

On 26 October 2060 the comet will pass roughly 0.047 AU (7,000,000 km; 4,400,000 mi) from the Earth.[9]

References[edit]

  1. ^ a b c "15P/Finlay Orbit". Minor Planet Center. Retrieved 2014-06-21. 
  2. ^ a b Syuichi Nakano (2011-11-05). "15P/Finlay (NK 2161)". OAA Computing and Minor Planet Sections. Retrieved 2012-02-18. 
  3. ^ Patrick Rocher (2009-03-20). "Note number : 0094 P/Finlay : 15P". Institut de mécanique céleste et de calcul des éphémérides. Retrieved 2012-02-19. 
  4. ^ Comet II (2004) pg 242
  5. ^ Seiichi Yoshida (2010-07-31). "15P/Finlay (2014)". Seiichi Yoshida's Comet Catalog. Retrieved 2012-02-22. 
  6. ^ Kronk, Gary W. "15P/Finlay". Cometography. Retrieved 2007-01-31. 
  7. ^ a b Bob King. "Comet Finlay in Bright Outburst, Visible in Small Telescopes". Universe Today. Retrieved 2014-12-20. 
  8. ^ Michael Mattiazzo. "24324Re: [comets-ml] Re: Possible another outburst of 15P/Finlay?". Yahoo: comet-ml. Retrieved 2015-01-17. 
  9. ^ "JPL Close-Approach Data: 15P/Finlay" (last observation: 2009-03-20; arc: 41.68 years). Retrieved 2014-11-01. 

External links[edit]

Periodic comets (by number)
Previous
14P/Wolf
15P/Finlay Next
16P/Brooks