67P/Churyumov-Gerasimenko
Metadata
| Parameter | Value |
|---|---|
| Designation | 67P/Churyumov-Gerasimenko |
| Type | P |
| Perihelion (tp_cal, UTC) | 2015-08-13T02:07:40.042560Z |
| Orbit solution date (soln_date, UTC) | 2024-02-01T08:49:50Z |
| Obs used | 8608 |
| NEO | Yes |
| M1 | 12.900 |
| K1 | 7.500 |
| PC | - |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2015-10-10.0000000 |
| e | 0.64090813 |
| q (au) | 1.243266 |
| a (au) | 3.462249 |
| i (deg) | 7.040295 |
| Ω (om, deg) | 50.135574 |
| ω (w, deg) | 12.798250 |
| M (ma, deg) | 8.859927 |
Magnitude
Scatter + Global Linear
$$ M_a = (12.809 + 3.261\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 12.809 |
| n | 3.261 |
| gf | 0.959 |
| gb | -0.500 |
| k | 0.800 |
| δ90 | 1.384 |
| Parameter | Symbol | Range | Description |
|---|---|---|---|
| Absolute magnitude at 1 AU from Sun and Earth | H0 | -5 to 20 | Intrinsic brightness of the comet |
| Photometric slope parameter | n | 2 to 6 | Rate of brightness change with heliocentric distance |
| Forward scattering asymmetry factor | gf |
0.8 to 1 | Degree of forward scattering |
| Backward scattering asymmetry factor | gb |
-1 to -0.5 | Degree of backward scattering |
| Partitioning coefficient | k | 0.8 to 1 | Ratio between forward/backward scattering contributions |
| Dust-to-gas brightness ratio | δ90 | 1 to 10 | Relative contribution of dust scattering to gas emission |
Reference: EPSC-DPS2025-160
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) | End (UTC) | a | b |
|---|---|---|---|
| 2021-02-02 | 2023-04-26 | -0.2979 | -0.513 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Finding Chart
Ephemeris
| Date/Time (UTC) | RA (J2000) | Dec (J2000) | Nearest HIP | Dist from HIP (arcmin) |
|---|---|---|---|---|
| 2026-06-01 00:00 | 17:36:32.34 | -26:46:49.3 | HIP 86265 | 14.28 |
| 2026-06-01 12:00 | 17:36:10.31 | -26:46:50.6 | HIP 86110 | 17.70 |
| 2026-06-02 00:00 | 17:35:48.17 | -26:46:51.5 | HIP 86020 | 14.04 |
| 2026-06-02 12:00 | 17:35:25.93 | -26:46:51.8 | HIP 86020 | 9.19 |
| 2026-06-03 00:00 | 17:35:03.59 | -26:46:51.7 | HIP 86020 | 4.59 |
| 2026-06-03 12:00 | 17:34:41.15 | -26:46:51.2 | HIP 86020 | 2.72 |
| 2026-06-04 00:00 | 17:34:18.62 | -26:46:50.1 | HIP 86020 | 6.64 |
| 2026-06-04 12:00 | 17:33:56.00 | -26:46:48.6 | HIP 86020 | 11.48 |
| 2026-06-05 00:00 | 17:33:33.29 | -26:46:46.5 | HIP 86020 | 16.47 |
| 2026-06-05 12:00 | 17:33:10.50 | -26:46:44.0 | HIP 86020 | 21.51 |
| 2026-06-06 00:00 | 17:32:47.63 | -26:46:41.0 | HIP 86020 | 26.59 |
| 2026-06-06 12:00 | 17:32:24.68 | -26:46:37.6 | HIP 86020 | 31.69 |
| 2026-06-07 00:00 | 17:32:01.65 | -26:46:33.6 | HIP 85783 | 30.63 |
| 2026-06-07 12:00 | 17:31:38.56 | -26:46:29.2 | HIP 85681 | 29.50 |
| 2026-06-08 00:00 | 17:31:15.40 | -26:46:24.2 | HIP 85681 | 27.42 |
| 2026-06-08 12:00 | 17:30:52.17 | -26:46:18.8 | HIP 85681 | 26.21 |
| 2026-06-09 00:00 | 17:30:28.89 | -26:46:12.8 | HIP 85538 | 22.22 |
| 2026-06-09 12:00 | 17:30:05.55 | -26:46:06.4 | HIP 85538 | 17.04 |
| 2026-06-10 00:00 | 17:29:42.16 | -26:45:59.5 | HIP 85538 | 11.87 |
| 2026-06-10 12:00 | 17:29:18.72 | -26:45:52.1 | HIP 85538 | 6.76 |
| 2026-06-11 00:00 | 17:28:55.23 | -26:45:44.2 | HIP 85538 | 2.29 |
| 2026-06-11 12:00 | 17:28:31.70 | -26:45:35.8 | HIP 85538 | 4.46 |
| 2026-06-12 00:00 | 17:28:08.14 | -26:45:26.9 | HIP 85538 | 9.48 |
| 2026-06-12 12:00 | 17:27:44.54 | -26:45:17.5 | HIP 85538 | 14.68 |
| 2026-06-13 00:00 | 17:27:20.91 | -26:45:07.7 | HIP 85538 | 19.92 |
| 2026-06-13 12:00 | 17:26:57.26 | -26:44:57.3 | HIP 85292 | 21.94 |
| 2026-06-14 00:00 | 17:26:33.58 | -26:44:46.5 | HIP 85292 | 18.47 |
| 2026-06-14 12:00 | 17:26:09.89 | -26:44:35.2 | HIP 85292 | 16.02 |
| 2026-06-15 00:00 | 17:25:46.18 | -26:44:23.4 | HIP 85292 | 15.11 |
| 2026-06-15 12:00 | 17:25:22.46 | -26:44:11.1 | HIP 85189 | 15.51 |
| 2026-06-16 00:00 | 17:24:58.74 | -26:43:58.3 | HIP 85189 | 12.69 |
| 2026-06-16 12:00 | 17:24:35.01 | -26:43:45.0 | HIP 85189 | 11.73 |
| 2026-06-17 00:00 | 17:24:11.29 | -26:43:31.3 | HIP 85189 | 13.06 |
| 2026-06-17 12:00 | 17:23:47.58 | -26:43:17.1 | HIP 85189 | 16.12 |
| 2026-06-18 00:00 | 17:23:23.87 | -26:43:02.5 | HIP 85189 | 20.13 |
| 2026-06-18 12:00 | 17:23:00.18 | -26:42:47.3 | HIP 84931 | 24.60 |
| 2026-06-19 00:00 | 17:22:36.50 | -26:42:31.7 | HIP 84931 | 20.09 |
| 2026-06-19 12:00 | 17:22:12.85 | -26:42:15.7 | HIP 84931 | 16.07 |
| 2026-06-20 00:00 | 17:21:49.23 | -26:41:59.2 | HIP 84931 | 13.00 |
| 2026-06-20 12:00 | 17:21:25.63 | -26:41:42.2 | HIP 84931 | 11.63 |
| 2026-06-21 00:00 | 17:21:02.07 | -26:41:24.8 | HIP 84851 | 10.96 |
| 2026-06-21 12:00 | 17:20:38.54 | -26:41:07.0 | HIP 84851 | 8.32 |
| 2026-06-22 00:00 | 17:20:15.06 | -26:40:48.7 | HIP 84851 | 8.57 |