- 35P/Herschel-Rigollet
Infobox Comet
name=35P/Herschel-Rigollet
caption=
discoverer=Caroline Herschel &Roger Rigollet
discovery_date=1788-12-21 &1939-07-28
designations=35P/1788 Y1, 1788II Herschel; 1939 O1, 1939 IX
epoch=1939-08-05
aphelion= 56,9386 AU
perihelion=1.20 AU
semimajor=28,8435 AU AU
semiminor=
orbital_circ=
eccentricity=0.9741
period=154.911 a
avg_speed=
max_speed=
min_speed=
inclination= 64,207°
last_p=1939-08-09
next_p=2092-03-16 35P/Herschel-Rigollet is a
periodic comet discovered byCaroline Herschel (Slough ,United Kingdom ) on1788-12-21 .1789 apparition
Caroline Herschel first observed the comet on 21 December 1788 and it was observed later that night by her brother
William Herschel who described it as looking like a brightnebula and about 5-6minute s in diameter, and much larger than theplanetary nebula M57.Through December and January the comet was observed by
Nevil Maskelyne at theGreenwich Observatory and byCharles Messier at theParis Observatory . Maskelyne was the last observer of the comet, his final observation taking place on1789-02-05 .Similar possible
orbit s for the comet were calculated in 1789 byPierre Méchain and in 1922 byMargaretta Palmer . Palmer considered that the orbit which best fitted the observations was an elliptical one with a period of 1,066 years.1939 apparition
Roger Rigollet (
Lagny ,France ) rediscovered the comet on1939-07-28 ; it was described as diffuse and with a magnitude of 8.0. The sighting was confirmed the next day byAlfonso Fresa of theObservatory of Turin (Italy ) andGeorge van Biesbroeck of theYerkes Observatory . The comet steadily faded after August, final (photographic) observations being obtained on1940-01-16 .Following the 1939 rediscovery, the comets orbit was calculated by
Jens P. Möller (Copenhagen ,Denmark ), andKatherine P. Kaster andThomas Bartlett (Berkeley , USA). Aperihelion date of1939-08-09 was indicated. Based on these early orbits,Leland E. Cunningham of theHarvard College Observatory suggested that the comet was likely identical with Herschel's comet of 1788.The final calculation of the orbit, by
Brian G. Marsden in 1974, used 75 positions from both apparitions of the comet in 1788 and 1939-40 in addition to perturbations by planets, and linked the two sightings, with a perihelion date of1939-08-09 and a period of 155 years.Closest approaches to Earth
*
1788-11-04 - 0.80 AU from Earth
*1939-07-30 - 0.82 AU from EarthReferences
*cite web | last = | first = | authorlink = | coauthors = | title = 35P/Herschel-Rigollet | work = Gary W. Kronk's Cometography | publisher = | date = | url = http://cometography.com/pcomets/035p.html | format = | doi = | accessdate = 2008-02-02
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