Table 3
Molecular abundances.
| Molecule | Name | Abundance relative to water in% | ||
|---|---|---|---|---|
| C/2021 A1 (Leonard) | C/2022 E3 (ZTF) | All comets | ||
| HCN | Hydrogen cyanide | 0.09 ± 0.01 | 0.09 ± 0.01 | 0.08–0.25 |
| HNC | Hydrogen isocyanide | 0.005 ± 0.0005 | 0.0015 ± 0.0003 | 0.0015–0.035 |
| HNCd(a) | 0.006 ± 0.0007 | 0.0032 ± 0.0006 | ||
| CH3CN | Methyl cyanide | 0.016 ± 0.001 | 0.017 ± 0.001 | 0.008–0.054 |
| HC3N | Cyanoacetylene | 0.004 ± 0.001 | <0.0022 | 0.002–0.068 |
| HNCO | Isocyanic acid | 0.073 ± 0.008 | 0.042 ± 0.004 | <0.01–0.62 |
| NH2CHO | Formamide | 0.023 ± 0.002 | 0.019 ± 0.001 | 0.015–0.022 |
| CO | Carbon monoxide | <2.0 | 0.7 ± 0.3 | 0.4–35 |
| H2CO | Formaldehyde | 0.12 ± 0.01 | 0.12 ± 0.01 | |
| H2COd(b) | 0.26 ± 0.01 | 0.22 ± 0.01 | 0.13–1.4 | |
| CH3OH | Methanol | 0.88 ± 0.02 | 1.76 ± 0.01 | 0.7–6.1 |
| HCOOH | Formic acid | 0.19 ± 0.02 | 0.19 ± 0.01 | <0.04–0.58 |
| CH3CHO | Acetaldehyde | 0.036 ± 0.009 | 0.070 ± 0.004 | 0.05–0.08 |
| (CH2OH)2 | Ethylene-glycol | 0.13 ± 0.03 | 0.13 ± 0.02 | 0.07–0.35 |
| C2H5OH | Ethanol | 0.18 ± 0.04 | 0.17 ± 0.03 | 0.11–0.19 |
| CH2OHCHO | Glycolaldehyde | 0.051 ± 0.012 | <0.024 | 0.016–0.039 |
| CH2CO | Ketene | 0.033 ± 0.015 | <0.03 | ≤0.0078 |
| HCOOCH3 | Methyl formate | <0.15 | <0.10 | 0.06–0.08 |
| c-C2H4O | Ethylene-oxide | <0.024 | <0.017 | <0.029 |
| H2S | Hydrogen sulphide | 0.15 ± 0.02 | 0.18 ± 0.04 | 0.09–1.5 |
| CS | Carbon monosulphide | 0.06 ± 0.01 | 0.049 ± 0.004 | 0.05–0.20 |
| CSd(c) | 0.10 ± 0.01 | 0.075 ± 0.003 | 0.05–0.20 | |
| OCS | Carbonyl sulphide | 0.11 ± 0.03 | 0.068 ± 0.016 | 0.05–0.40 |
| SO | Sulphur monoxide | <0.04 | <0.03 | 0.04–0.30 |
| SO2 | Sulphur dioxide | <0.04 | <0.03 | 0.03–0.23 |
| H2CS | Thioformaldehyde | <0.03 | <0.02 | 0.009–0.090 |
| CH3SH | Methyl mercaptan | <0.08 | <0.06 | <0.06 |
| c-C3H2 | Cyclopropenylidene | <0.024 | <0.011 | <0.009 |
| l-C3H2 | Propadienylidene | <0.004 | <0.002 | <0.0026 |
| PH3 | Phosphine | <0.16 | <0.09 | <0.07 |
Notes. Molecules with a “d” are modelled with a daughter distribution with the following parent scale length: (a)Assuming a daughter distribution with Lp = 1000 and 2000 km (Cordiner et al. 2014, 2017). (b) Assuming a daughter distribution with Lp = 1500 and 1700 km (fitted values for C/2021 A1 and C/2022 E3).(c) Assuming a daughter distribution with Lp = 4 × L(CS2).
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.