J/A+A/633/A80 122 long-period comets non-gravitational param. (Krolikowska 2020)
Non-gravitational effects change the original 1/a-distribution of real
near-parabolic comets
Krolikowska M.
<Astron. Astrophys. 633, A80 (2020)>
=2020A&A...633A..80K 2020A&A...633A..80K (SIMBAD/NED BibCode)
ADC_Keywords: Solar system ; Comets
Keywords: comets: general - Oort Cloud
Abstract:
The original 1/a-distribution is the only observational basis for the
origin of long-period comets (LPCs) and the dynamical properties of
the Oort Cloud. Although they are very subtle in the motion of these
comets, non-gravitational effects can cause major changes in the
original semimajor axis, 1/aori We obtained reliable
non-gravitational orbits for as many LPCs with small perihelion
distances of q<3.1au as possible, and determined the corresponding
shape of the Oort spike.
We determined the osculating orbits of each comet using several
data-processing methods, and selected the preferred orbit using a few
specific criteria. The distribution of 1/aori for the whole comet
sample was constructed using the individual Gaussian distribution we
obtained for the preferred solution of each comet.
The derived distribution of 1/aori for almost all known
small-perihelion Oort spike comets was based on 64% of the
non-gravitational orbits. This was compared with the distribution
based on purely gravitational orbits, as well as with 1/aori
constructed earlier for LPCs with q>3.1 au. We present a statistical
analysis of the magnitudes of the non-gravitational acceleration for
about 100∼LPCs. The 1/aori-distribution, which is based mainly on
the non-gravitational orbits of small-perihelion Oort spike comets, is
shifted by about 10x10-6au-1 to higher values of 1/aori
compared with the distribution that is obtained when the
non-gravitational effects on comet motion are ignored. We show the
differences in the 1/aori-distributions between LPCs with q<3.1au
and those with q>3.1au. These findings indicate the important role of
non-gravitational∼acceleration in the motion and origin of LPCs and in
the formation of the Oort Cloud.
Description:
The Catalogue includes a non-gravitational parameters and original and
future reciprocals of semimajor axes for the sample of 122 long-period
comets with small perihelion distances (q<3.1au) and original
1/aori<0.000100au-1 for purely GR orbits. This is an almost
complete sample of such objects discovered in the period 1885-2012.
The orbits of the majority of these comets were presented in
Krolikowska, 2014A&A...567A.126K 2014A&A...567A.126K (Cat. J/A+A/567/A126), see below for
more references.
The full orbital parameters, that is, osculating orbits, original and
future orbits will be prepared in the middle of 2020.
Based on the diverse impact of the NG effects on the orbital fitting to
the positional data, the division of the whole sample of the LPCs into
four subgroups is given; for more see the source paper.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 42 122 *List of comets
table3.dat 142 107 Non-gravitational (NG) parameters for comets
with non-gravitational solutions taken as
preferred solutions
tablea1.dat 222 76 Description of observational material, orbit
quality assessment, and original and future
semimajor axis for Oort spike comets with
purely gravitational orbit determinable
(non-gravitational orbit is indeterminable)
tablea2.dat 225 52 Description of observational material, orbit
quality assessment, and original and future
semimajor axis for Oort spike comets with
non-gravitational orbit determinable (comets
lost close to perihelion or split comets)
tablea3.dat 192 120 Description of observational material, orbit
quality assessment, and original and future
semimajor axis for Oort spike comets with
non-gravitational orbit determinable (comets
with NG effects strongly manifested in
positional data fitting)
tablea4.dat 195 167 Description of observational material, orbit
quality assessment, and original and future
semimajor axis for Oort spike comets with
non-gravitational orbit determinable (comets
with determinable NG orbit - more or less
typical cases)
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Note on table1.dat: with the orbit quality assessment, type of solution (purely
gravitational or non-gravitational) and name of the tables where are original
and future semimajor axes with positional data description used for orbital
determination.
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See also:
J/A+A/567/A126 : Warsaw Catalogue of cometary orbits (Krolikowska, 2014)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1 A1 --- Sample [ABC] Sample name (1)
3- 17 A15 --- Desig Comet's designation
18- 23 A6 --- or-t Type of model used to orbit determination (2)
24- 26 A3 --- or-qual orbital quality assessment based on
the method given in KD13 (Krolikowska and
Dybczynski, 2013MNRAS.435..440K 2013MNRAS.435..440K)
28- 38 A11 --- Table Table designation with data description used
for orbit determination, and original and
future reciprocals of semimajor axes
40- 42 A3 --- Pref Key informing whether original semimajor axis
is based on new orbital determination (new)
or on orbit previously published (old)
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Note (1): Sample as follows:
A = Comets discovered before 1900
B = Complete sample of small-perihelion Oort spike comets discovered in the
years 1901-1950 taken from Krolikowska et al. (2014, Cat. J/A+A/567/A126)
C = Comets discovered in the period 1951-2012; in the beginning objects with
purely GR orbits are listed
Note (2): Type of model used to orbit determination as follows:
GR = purely gravitational orbit
NG = non-gravitational (NG) orbit based on standard g(r)-function
NG(CO) = NG orbit based on CO-sublimation
NG2p = indicates that two solutions are preffered depending on whether we
assume water-ice sublimation or CO-ice sublimation
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 A2 --- Tab Table number (1)
4- 15 A12 --- Desig Comet's designation
16 A1 --- Type [SC] 'S' means g(r) function for water ice
sublimation, 'C' means CO sublimation
17- 18 A2 --- Model internal model name
20- 26 F7.5 au qosc Osculating perihelion distance
28- 37 F10.6 10-8au/d+2 A1 Radial component of NG parameter (2)
39- 48 F10.6 10-8au/d+2 e_A1 Uncertainty of the radial component of NG
parameter(2)
50- 59 F10.6 10-8au/d+2 A2 Transverse component of NG parameter (2)
61- 69 F9.6 10-8au/d+2 e_A2 Uncertainty of transverse component of
NG parameter(2)
71- 80 F10.6 10-8au/d+2 A3 Normal component of NG parameter (2)
82- 89 F8.6 10-8au/d+2 e_A3 Uncertainty of normal component of NG
parameter (2)
91- 95 F5.2 --- m m-exponent in g(r)-like function (3)
97-101 F5.3 --- n n-exponent in g(r)-like function (3)
103-109 F7.4 --- k k-exponent in g(r)-like function (3)
111-116 F6.3 au r0 Distant scale in g(r)-like function of
NG acceleration (3)
118-125 F8.6 --- alpha Normalization constant in g(r)-like
function of NG acceleration (3)
127-134 F8.4 d DT time shift of maximum g(r)-function
relative to perihelion passage
136-142 F7.4 d e_DT uncertainty of DT
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Note (1): Table number (A2-A4) where the small-perihelion comets are presented.
Preferred solution is in the first line for a given comet.
Note (2): in 10-8AU/day2 unit.
Note (3): standard g(r)-function (water sublimation):
alpha r0 m n k
0.1113 2.808 -2.15 5.093 -4.6142
standard g(r)-like function (CO sublimation):
alpha r0 m n k
0.01003 10.0 -2.0 3.0 -2.6
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Byte-by-byte Description of file: tablea?.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Desig Comet's designation
14- 33 A20 --- Cname Comet's designation
34- 40 F7.4 au qosc ? osculating perihelion distance
42- 43 A2 --- n3 The internal model name used in the database
45- 52 I8 "YYYYMMDD" Time ? Perihelion time [TT]
54 I1 -- z [1/4]? key for a qualitative description of
impact of NG effects on positional data
fitting (2)
56- 63 I8 "YYYYMMDD" arc1 Date of first observation taken for orbit
determination [TT]
65- 72 I8 "YYYYMMDD" arc2 Date of last observation taken for orbit
determination [TT]
74- 77 I4 --- Nobs ? Number of used (1)
79- 83 F5.3 yr arcy ? Interval of data taken for orbit
determination (arc in years)
85- 90 F6.3 au dh1 ? Heliocentric distance of first observation
taken to orbit determination
91- 96 F6.3 au dh2 ? Heliocentric distance of last observation
taken to orbit determination
98-104 A7 --- datat Data type in the sense of time-distribution
around perihelion:
PRE/PRE+/FULL/POST/POST+ /POST++/PRE++
106-109 A4 --- Model Model type:
GR = gravitational, NG = non-gravitational
111-113 F3.1 --- Q*GR ? Accuracy of gravitational orbit
115-117 F3.1 --- Q*NG ? Accuracy of non-gravitational orbit
when determinable
119-121 A3 --- Qlnew Quality orbit assessment according to
Krolikowska and Dybczynski,
2013MNRAS.435..440K 2013MNRAS.435..440K
123-126 F4.2 arcsec RMS ? Root-mean-square error
128-132 I5 --- Nres ? Number of residuals taken for orbit
determination for a given model
134-139 A6 --- Ref References to the solution (3)
140-142 A3 --- arcS Type of data arc selection for orbit
determination (4)
144-147 A4 --- dataW [YES/NO+ ] Flag data weigthing, YES/NO
149-152 A4 --- orbP Flag of prefered orbit;
usually YES+/NO (for arc_s.eq.'STD') (5)
154-155 A2 --- ngType Type of NG solution (for NG only) (6)
157-164 F8.2 10-8/au 1/aori ? Inverse original semimajor axis
166-172 F7.2 10-8/au e_1/aori ? Uncertainty of inverse original
semimajoraxis
174-182 F9.2 10-8/au 1/afut ? Inverse future semimajor axis
184-191 F8.2 10-8/au e_1/afut ? Uncertainty of inverse future semimajor
axis
193-225 A33 --- Notes Additional Notes
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Note (1): Number of used (available-ejected) observations if arc_s.eq.'STD'
then all available observation were taken to selection procedure of orbit
determination
Note (2): z keys as follows:
1 = NG effects not determinable
2 = Comet lost close to perihelion or split comet
3 = Comet with NG effects strongly manifested in positional data fitting
4 = Comet with determinable NG orbit
Note (3): References as follows:
P1 = Krolikowska and Dybczynski, 2010MNRAS.404.1886K 2010MNRAS.404.1886K
P2 = Dybczynski and Krolikowska, 2011MNRAS.416...51D 2011MNRAS.416...51D
P3 = Krolikowska, Dybczynski and Sitarski, 2012A&A...544A.119K 2012A&A...544A.119K
P4 = Krolikowska and Dybczynski, 2013MNRAS.435..440K 2013MNRAS.435..440K
P5 = Krolikowska, 2014A&A...567A.126K 2014A&A...567A.126K, Cat. 2014A&A...567A.126K 2014A&A...567A.126K
P6 = Krolikowska et al., 2014A&A...571A..63K 2014A&A...571A..63K, J/A+A/571/A63
P7 = Krolikowska and Dybczynski, 2017MNRAS.472.4634K 2017MNRAS.472.4634K, Cat. J/MNRAS/472/4634
P8 = Dybczynski and Krolikowska, 2018/2019, in preparation
PB = Krolikowska and Dybczynski, 2016MNRAS.460.2905K 2016MNRAS.460.2905K
MPC = solution retrieved from the Minor Planet Center before 1 November 2019
(https://www.minorplanetcenter.net/db_search/)
NK**** = solution retrieved from the Nakano Notes before 1 November 2019
(http://www.oaa.gr.jp/~oaacs/nk.htm)
NL**** = number of Nakano Notes
S1 = Sekanina, 2019, arXiv:1903:6300
Note (4): type of data arc selection for orbit determination as follows:
STD = standard - all data included;
PRE = pre-perihelion data taken only
POS = post-perihelion data taken only
DIS = data in large heliocentric distances taken only,
NEA = around perihelion up to assumed upper limit of heliocentric distance
Note (5): Flag as follows:
YE1 = preffered for past evolution only, arc_s.eq.'PRE', lack of future orbit
YE2 = preffered for future evolution only, arc_s.eq.'POS',
lack of original orbit
YOS = dedicated g(r)-like function taking into account photometric data
(for arc_s.eq.'STD' or arc_s.eq.'DIS')
YO1 = dedicated g(r)-like function taking into account photometric data
(preffered for past evolution only, arc_s.eq.'PRE')
YO2 = dedicated g(r)-like function taking into account photometric data
(preffered for future evolution only, arc_s.eq.'POS')
Note (6): type of NG solution code as follows:
NS = standard symmetric g(r)-function,
NT = asymmetrical g(r-tau)-function, 4 NG-par
NN = dedicated form of g(r)-like function,
NC = symmetric g(r)-like function dedicated for CO-sublimation,
CT = asymmetric g(r)-like function dedicated for CO-sublimation.
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Acknowledgements:
Malgorzata Krolikowska, mkr(at)cbk.waw.pl,
Space Research Centre PAS, Poland
(End) M. Krolikowska [SRC PAS, Poland], P. Vannier [CDS] 29-Nov-2019