Table 3.1 Composition of the coma of 67P relative to water vapour obtained in October 2014,
10 km from the centre of mass (Le Roy et al. 2015)
Species
Northern summer
hemisphere
[H 2 O ¼ 100]
Southern winter
hemisphere
[H 2 O ¼ 100]
Selected derived bulk
abundance [H 2 O ¼ 100]
H 2 O
100
a
100
a
100
a
O 2
3.1 Æ 1.1
CO
2.7
20
3.1 Æ 0.9
CO 2
2.5
80
4.7 Æ 1.4
CH 4
0.13
0.56
0.34 Æ 0.07
C 2 H 2
0.045
0.55
C 2 H 6
0.32
3.3
0.29 Æ 0.06
CH 3 OH
0.31
0.55
0.21 Æ 0.06
C 2 H 5 OH
0.039 Æ 0.023
C 3 H 8
0.018 Æ 0.004
C 6 H 6
0.00069 Æ 0.00014
C 7 H 8
0.0062 Æ 0.0012
H 2 CO
0.33
0.53
0.32 Æ 0.10
HCOOH
0.008
0.03
0.013 Æ 0.008
CH 2 OHCH 2 OH 0.0008
2.5e-3
0.011 Æ 0.007
HCOOCH 3
0.004
0.023
0.0034 Æ 0.0020
CH 3 CHO
0.01
0.024
0.047 Æ 0.017
N 2
0.089 Æ 0.024
NH 2 CHO
<1e-4
<1e-3
NH 3
0.06
0.15
0.67 Æ 0.20
HCN
0.09
0.62
0.14 Æ 0.04
HNCO
0.016
0.031
0.027 Æ 0.016
HNC
b
b
CH 3 CN
0.006
0.016
0.0059 Æ 0.0034
HC 3 N
<2e-5
<5e-4
0.00040 Æ 0.00023
S
0.46 Æ 0.36
H 2 S
0.67
1.75
1.10 Æ 0.46
OCS
0.017
0.098
0:041
þ0:082
À0:020
SO
0.004
0.0014
0:071
þ0:142
À0:037
SO 2
0.011
0.041
0:127
þ0:254
À0:064
CS
c
c
CS 2
0.003
0.024
0:0057
þ0:0114
À0:0028
S 2
0.0004
0.0013
0:0020
þ0:0040
À0:0010
The list contains all species found at comets prior to Rosetta and the corresponding variation in
abundance measured by the ROSINA mass spectrometer above the northern and southern hemispheres of the comet. The right column provides the bulk abundance determined by Rubin et al.
(2019) and references therein
a Definition
b
Cannot be distinguished from HCN
c Cannot be resolved from CO 2
182
3 Gas Emissions Near the Nucleus
10 km from the centre of mass (Le Roy et al. 2015)
Species
Northern summer
hemisphere
[H 2 O ¼ 100]
Southern winter
hemisphere
[H 2 O ¼ 100]
Selected derived bulk
abundance [H 2 O ¼ 100]
H 2 O
100
a
100
a
100
a
O 2
3.1 Æ 1.1
CO
2.7
20
3.1 Æ 0.9
CO 2
2.5
80
4.7 Æ 1.4
CH 4
0.13
0.56
0.34 Æ 0.07
C 2 H 2
0.045
0.55
C 2 H 6
0.32
3.3
0.29 Æ 0.06
CH 3 OH
0.31
0.55
0.21 Æ 0.06
C 2 H 5 OH
0.039 Æ 0.023
C 3 H 8
0.018 Æ 0.004
C 6 H 6
0.00069 Æ 0.00014
C 7 H 8
0.0062 Æ 0.0012
H 2 CO
0.33
0.53
0.32 Æ 0.10
HCOOH
0.008
0.03
0.013 Æ 0.008
CH 2 OHCH 2 OH 0.0008
2.5e-3
0.011 Æ 0.007
HCOOCH 3
0.004
0.023
0.0034 Æ 0.0020
CH 3 CHO
0.01
0.024
0.047 Æ 0.017
N 2
0.089 Æ 0.024
NH 2 CHO
<1e-4
<1e-3
NH 3
0.06
0.15
0.67 Æ 0.20
HCN
0.09
0.62
0.14 Æ 0.04
HNCO
0.016
0.031
0.027 Æ 0.016
HNC
b
b
CH 3 CN
0.006
0.016
0.0059 Æ 0.0034
HC 3 N
<2e-5
<5e-4
0.00040 Æ 0.00023
S
0.46 Æ 0.36
H 2 S
0.67
1.75
1.10 Æ 0.46
OCS
0.017
0.098
0:041
þ0:082
À0:020
SO
0.004
0.0014
0:071
þ0:142
À0:037
SO 2
0.011
0.041
0:127
þ0:254
À0:064
CS
c
c
CS 2
0.003
0.024
0:0057
þ0:0114
À0:0028
S 2
0.0004
0.0013
0:0020
þ0:0040
À0:0010
The list contains all species found at comets prior to Rosetta and the corresponding variation in
abundance measured by the ROSINA mass spectrometer above the northern and southern hemispheres of the comet. The right column provides the bulk abundance determined by Rubin et al.
(2019) and references therein
a Definition
b
Cannot be distinguished from HCN
c Cannot be resolved from CO 2
182
3 Gas Emissions Near the Nucleus