116P/Wild 4

Comet 116P/Wild 4 was the fourth and last of the periodic comets discovered on January 21st 1980 at Zimmerwald by Paul Wild of The Astronomical Institute of Berne University (Switzerland) . The comet was approximately magnitude 13.5 and strongly condensed, with a fanshaped tail extending about 1' to the northwest.

Calculations by Brian Marsden based on 6 positions covering an arc of just four days suggested that the comet was of short period. It is a measure of just how amateur CCD data has changed the way that comet orbits are calculated that there were just 6 positions in 4 days from discovery. These days such a bright ccomet would probably have at least many tens and possibly hundreds of astrometric observations in this amount of time. By February 14th 1990 with 14 observations spanning 21 days it was shown that the comet was of short period and a new member of the inner solar system. Prior to an encounter with Jupiter in July 1987 the comet had an almost circular orbit just inside that of Jupiter. Total visual magnitude observations made after discovery showed that Comet Wild 4 peaked at around magnitude 12 in February 1990.

The comet was recovered by Jim Scotti at Spacewatch on November 9th 1994 at magnitude 20.7. On this occasion some estimates put the comet as bright as magnitude 11. The comet showed a very rapid rate of brightening with heliocentric distance typical of an evolved object. The orbit is evolving rapidly and the perihelion distance has increased again from 1.99AU (1990 and 1996) to 2.17AU (2003)

The current orbital period is 6.48 years. Perihelion was reached on 2003 January 21st.

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The light curve here is made up of CCD photometry in R with a 10" aperture (shown as m(10)) and total visual and total CCD magnitude estimates. Peak brightness appears to have been reached in the CCD photometry in early May 2003, although the total visual magnitude has continued to increase well past then.

Photometrically the comet has shown a much slower rate of increase in brightness with decreasing heliocentric distance and a much fainter absolute magnitude than in 1996.

 

 

 

 

 

 

 

 

 

 

 

Observations from:

  • Isidro Almendros – MPC 212
  • Ramón Naves & Montse Campàs - MPC 213
  • Rolando Ligustri – MPC 235
  • Esteban Reina – MPC 232
  • Diego Rodríguez – MPC 458
  • Julio Castellano – MPC 939
  • José Ramón Vidal – MPC 945
  • Fernanda Artigue & Mark Kidger – MPC 954
  • Joseph Lluís Salto – MPC A02
  • Quim Moreno – MPC A03
  • Toni Climent – MPC J97

 

Visual observations by:

    • Rafael Benavides
    • Carlos Labordena
    • Joaquín Tapioles
    • Juan José González

 


Última actualización 12/06/2003
Por M.R.Kidger