173P/Mueller 5
Metadata
| Parameter | Value |
|---|---|
| Designation | 173P/Mueller 5 |
| Type | P |
| Perihelion (tp_cal, UTC) | 2008-05-15T15:31:24.496320Z |
| Orbit solution date (soln_date, UTC) | 2023-06-30T22:18:07Z |
| Obs used | 1194 |
| NEO | - |
| M1 | 12.100 |
| K1 | 4.500 |
| PC | - |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2012-02-21.0000000 |
| e | 0.26135639 |
| q (au) | 4.203777 |
| a (au) | 5.691211 |
| i (deg) | 16.505508 |
| Ω (om, deg) | 100.496504 |
| ω (w, deg) | 29.393323 |
| M (ma, deg) | 99.914136 |
Magnitude
Scatter + Global Linear
$$ M_a = (13.418 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 13.418 |
| n | 2.000 |
| gf | 0.983 |
| gb | -0.612 |
| k | 0.800 |
| δ90 | 9.998 |
| 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 |
|---|---|---|---|
| 2018-10-31 | 2020-03-17 | -28.6764 | +18.841 |
| 2020-03-17 | 2023-04-15 | +26.0210 | -18.793 |
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) |
|---|---|---|---|---|
| 2026-05-12 00:00 | 18:21:36.13 | -19:34:39.8 | HIP 89917 | 23.62 |
| 2026-05-12 12:00 | 18:21:28.05 | -19:35:00.4 | HIP 89917 | 22.53 |
| 2026-05-13 00:00 | 18:21:19.83 | -19:35:21.2 | HIP 89917 | 21.54 |
| 2026-05-13 12:00 | 18:21:11.47 | -19:35:42.2 | HIP 89917 | 20.69 |
| 2026-05-14 00:00 | 18:21:02.97 | -19:36:03.4 | HIP 89917 | 19.99 |
| 2026-05-14 12:00 | 18:20:54.34 | -19:36:24.8 | HIP 89917 | 19.47 |
| 2026-05-15 00:00 | 18:20:45.57 | -19:36:46.4 | HIP 89917 | 19.16 |
| 2026-05-15 12:00 | 18:20:36.67 | -19:37:08.2 | HIP 89917 | 19.08 |
| 2026-05-16 00:00 | 18:20:27.63 | -19:37:30.1 | HIP 89917 | 19.25 |
| 2026-05-16 12:00 | 18:20:18.47 | -19:37:52.3 | HIP 89917 | 19.66 |
| 2026-05-17 00:00 | 18:20:09.17 | -19:38:14.7 | HIP 89917 | 20.31 |
| 2026-05-17 12:00 | 18:19:59.74 | -19:38:37.2 | HIP 89917 | 21.19 |
| 2026-05-18 00:00 | 18:19:50.19 | -19:39:00.0 | HIP 89917 | 22.27 |
| 2026-05-18 12:00 | 18:19:40.51 | -19:39:22.9 | HIP 89917 | 23.55 |
| 2026-05-19 00:00 | 18:19:30.70 | -19:39:46.0 | HIP 89917 | 25.00 |
| 2026-05-19 12:00 | 18:19:20.77 | -19:40:09.3 | HIP 89647 | 23.73 |
| 2026-05-20 00:00 | 18:19:10.71 | -19:40:32.8 | HIP 89647 | 21.36 |
| 2026-05-20 12:00 | 18:19:00.54 | -19:40:56.5 | HIP 89647 | 18.97 |
| 2026-05-21 00:00 | 18:18:50.25 | -19:41:20.4 | HIP 89647 | 16.57 |
| 2026-05-21 12:00 | 18:18:39.83 | -19:41:44.4 | HIP 89647 | 14.16 |
| 2026-05-22 00:00 | 18:18:29.31 | -19:42:08.6 | HIP 89647 | 11.75 |
| 2026-05-22 12:00 | 18:18:18.66 | -19:42:33.0 | HIP 89647 | 9.37 |
| 2026-05-23 00:00 | 18:18:07.90 | -19:42:57.6 | HIP 89647 | 7.08 |
| 2026-05-23 12:00 | 18:17:57.03 | -19:43:22.3 | HIP 89647 | 5.04 |
| 2026-05-24 00:00 | 18:17:46.05 | -19:43:47.3 | HIP 89647 | 3.74 |
| 2026-05-24 12:00 | 18:17:34.96 | -19:44:12.3 | HIP 89647 | 4.05 |
| 2026-05-25 00:00 | 18:17:23.76 | -19:44:37.6 | HIP 89647 | 5.75 |
| 2026-05-25 12:00 | 18:17:12.46 | -19:45:03.0 | HIP 89647 | 8.01 |
| 2026-05-26 00:00 | 18:17:01.05 | -19:45:28.6 | HIP 89647 | 10.51 |
| 2026-05-26 12:00 | 18:16:49.54 | -19:45:54.4 | HIP 89647 | 13.12 |
| 2026-05-27 00:00 | 18:16:37.92 | -19:46:20.3 | HIP 89647 | 15.79 |
| 2026-05-27 12:00 | 18:16:26.21 | -19:46:46.3 | HIP 89647 | 18.52 |
| 2026-05-28 00:00 | 18:16:14.39 | -19:47:12.6 | HIP 89647 | 21.28 |
| 2026-05-28 12:00 | 18:16:02.48 | -19:47:38.9 | HIP 89647 | 24.08 |
| 2026-05-29 00:00 | 18:15:50.47 | -19:48:05.5 | HIP 89647 | 26.91 |
| 2026-05-29 12:00 | 18:15:38.37 | -19:48:32.2 | HIP 89647 | 29.77 |
| 2026-05-30 00:00 | 18:15:26.18 | -19:48:59.0 | HIP 89647 | 32.65 |
| 2026-05-30 12:00 | 18:15:13.89 | -19:49:26.0 | HIP 89262 | 32.74 |
| 2026-05-31 00:00 | 18:15:01.52 | -19:49:53.1 | HIP 89262 | 29.94 |
| 2026-05-31 12:00 | 18:14:49.05 | -19:50:20.4 | HIP 89262 | 27.15 |
| 2026-06-01 00:00 | 18:14:36.51 | -19:50:47.8 | HIP 89262 | 24.38 |
| 2026-06-01 12:00 | 18:14:23.87 | -19:51:15.4 | HIP 89262 | 21.65 |
| 2026-06-02 00:00 | 18:14:11.16 | -19:51:43.1 | HIP 89262 | 18.98 |