52P/Harrington-Abell (0052P)
TRY AGAIN 2028
Type: Periodic
Perihelion date: 5 October 2021
Perihelion distance (q): 1.8
Aphelion distance (Q) : 5.9
Period (years): 7.6
Eccentricity (e): 0.54
Inclination (i): 10.2
JPL orbit diagram
COBS lightcurve
Robert G. Harrington and George O. Abell (Palomar Observatory, California, USA)
discovered this comet on a plate taken on 22 March 1955, with the 122-cm Schmidt
camera during the National Geographic Society-Palomar Sky Survey. The comet was
estimated as magnitude 17, and was described as diffuse, with a central
condensation, and a tail less than 1° long. The comet was confirmed on photographic
plates exposed on 27 and 30 March. On the latter date, the nucleus was magnitude
19.0 and was surrounded by a faint coma.
Leland E. Cunningham (Leuschner Observatory, Berkeley, California, USA) computed
the first orbit which was published on 25 April 1955. It used the three initial Palomar
positions and indicated the comet was moving in an elliptical orbit. The perihelion date
was given as 18 December 1954, while the orbital period was 7.01 years. Because of
the comet's faintness, it was not followed for a long time during its discovery
apparition. George van Biesbroeck photographed it twice with the 82-inch reflector at
McDonald Observatory during the latter half of April. He estimated the magnitude as
19.5 on each occasion, and said the coma was 5 arc seconds across. The comet was
last seen on 18 May, when Elizabeth Roemer (Lick Observatory) obtained exposures
of 120- and 100-minute durations, respectively, with the 36-inch f/5.8 Crossley
reflector. She determined the magnitude as 19.2, and said the comet appeared
slightly diffuse.
The comet has been seen at every apparition, beginning with its first recovery on 26
January 1962 by Alan McClure. It tends to remain a faint object. Further appearances
came in 1962, 1969, 1976, 1983, and 1991. K. Muraoka took positions from the years
1955-1990 and predicted the comet would next pass perihelion on 27 January 1999.
The comet was recovered on 21 July 1998 by A. Maury (l'Observatoire de la Côte
d'Azur, France). Using the 0.9-m Schmidt reflector and a CCD, he was expecting a
comet faintly shining at a magnitude of 21 or 22, but instead detected a comet of
magnitude 12.2. This unusual brightness was confirmed the next night by several
observers who estimated the visual magnitude as 10.9 to 11.8. The coma was
between 1 and 3 arc minutes across. The comet's enhanced brightness continued for
many months and observers were reporting total magnitudes of about 11 around the
time the comet passed perihelion on 27 January 1999. The coma diameter was then
about 3 arc minutes across. The comet slowly faded during February and as March
began most visual observers were estimating the magnitude as between 11.5 and 12.
The coma was then slightly larger than 2 arc minutes. For most of first half of 1999,
the comet continued to maintain its enhanced brightness for visual observers,
although it finally dropped below magnitude 12 by the end of March, while the coma
diameter had declined to 2 arc minutes. Observations continued throughout April and
May. By the middle of the latter month, when previous brightness prediction formulas
indicated the comet would be faintly shining at magnitude 19.5, most visual observers
were still reporting the comet was between 12.7 and 13.0.
Observations (VEMag = visual equivalent magnitude)
Date
10x10 mag
Error
VEmag
Coma '
04-Apr-14
16.88
0.04
15.9
0.2
12-Apr-14
17.05
0.13
16.3
0.2
15-Apr-14
16.95
0.10
15.8
0.2
21-Apr-14
16.81
0.07
15.9
0.2
03-May-14
17.43
0.04
15.6
0.2
27-May-14
17.89
0.14
16.7
0.2
08-Jun-14
18.05
0.16
17.4
0.2
10-Jun-14
18.12
0.12
17.8
0.2
18-Jun-14
18.36
0.11
18.1
0.2