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 | 0.999 |
| 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) |
|---|---|---|---|---|
| 2026-09-20 00:00 | 17:46:22.55 | -21:54:25.4 | HIP 86931 | 18.61 |
| 2026-09-20 12:00 | 17:46:29.14 | -21:54:59.4 | HIP 86931 | 18.89 |
| 2026-09-21 00:00 | 17:46:35.87 | -21:55:33.4 | HIP 86931 | 19.33 |
| 2026-09-21 12:00 | 17:46:42.74 | -21:56:07.3 | HIP 86931 | 19.92 |
| 2026-09-22 00:00 | 17:46:49.76 | -21:56:41.2 | HIP 86931 | 20.66 |
| 2026-09-22 12:00 | 17:46:56.92 | -21:57:15.0 | HIP 86931 | 21.53 |
| 2026-09-23 00:00 | 17:47:04.23 | -21:57:48.7 | HIP 86931 | 22.54 |
| 2026-09-23 12:00 | 17:47:11.67 | -21:58:22.4 | HIP 86931 | 23.67 |
| 2026-09-24 00:00 | 17:47:19.26 | -21:58:56.0 | HIP 86931 | 24.90 |
| 2026-09-24 12:00 | 17:47:26.99 | -21:59:29.6 | HIP 86931 | 26.24 |
| 2026-09-25 00:00 | 17:47:34.85 | -22:00:03.1 | HIP 86931 | 27.67 |
| 2026-09-25 12:00 | 17:47:42.86 | -22:00:36.5 | HIP 87099 | 28.07 |
| 2026-09-26 00:00 | 17:47:51.01 | -22:01:09.9 | HIP 87099 | 27.53 |
| 2026-09-26 12:00 | 17:47:59.29 | -22:01:43.1 | HIP 87099 | 27.13 |
| 2026-09-27 00:00 | 17:48:07.71 | -22:02:16.4 | HIP 87099 | 26.88 |
| 2026-09-27 12:00 | 17:48:16.27 | -22:02:49.5 | HIP 87099 | 26.80 |
| 2026-09-28 00:00 | 17:48:24.96 | -22:03:22.6 | HIP 87099 | 26.88 |
| 2026-09-28 12:00 | 17:48:33.79 | -22:03:55.6 | HIP 87099 | 27.14 |
| 2026-09-29 00:00 | 17:48:42.76 | -22:04:28.5 | HIP 87099 | 27.57 |
| 2026-09-29 12:00 | 17:48:51.86 | -22:05:01.4 | HIP 87332 | 26.50 |
| 2026-09-30 00:00 | 17:49:01.09 | -22:05:34.2 | HIP 87332 | 24.71 |
| 2026-09-30 12:00 | 17:49:10.46 | -22:06:06.8 | HIP 87332 | 22.96 |
| 2026-10-01 00:00 | 17:49:19.96 | -22:06:39.5 | HIP 87332 | 21.29 |
| 2026-10-01 12:00 | 17:49:29.60 | -22:07:12.0 | HIP 87332 | 19.70 |
| 2026-10-02 00:00 | 17:49:39.36 | -22:07:44.4 | HIP 87332 | 18.24 |
| 2026-10-02 12:00 | 17:49:49.26 | -22:08:16.8 | HIP 87332 | 16.96 |
| 2026-10-03 00:00 | 17:49:59.29 | -22:08:49.1 | HIP 87332 | 15.91 |
| 2026-10-03 12:00 | 17:50:09.45 | -22:09:21.3 | HIP 87332 | 15.14 |
| 2026-10-04 00:00 | 17:50:19.74 | -22:09:53.3 | HIP 87332 | 14.73 |
| 2026-10-04 12:00 | 17:50:30.16 | -22:10:25.3 | HIP 87332 | 14.70 |
| 2026-10-05 00:00 | 17:50:40.71 | -22:10:57.2 | HIP 87332 | 15.09 |
| 2026-10-05 12:00 | 17:50:51.39 | -22:11:29.1 | HIP 87332 | 15.87 |
| 2026-10-06 00:00 | 17:51:02.20 | -22:12:00.8 | HIP 87458 | 16.61 |
| 2026-10-06 12:00 | 17:51:13.13 | -22:12:32.4 | HIP 87458 | 14.21 |
| 2026-10-07 00:00 | 17:51:24.19 | -22:13:03.9 | HIP 87458 | 11.85 |
| 2026-10-07 12:00 | 17:51:35.38 | -22:13:35.3 | HIP 87458 | 9.60 |
| 2026-10-08 00:00 | 17:51:46.70 | -22:14:06.6 | HIP 87458 | 7.58 |
| 2026-10-08 12:00 | 17:51:58.13 | -22:14:37.8 | HIP 87458 | 6.07 |
| 2026-10-09 00:00 | 17:52:09.70 | -22:15:08.9 | HIP 87458 | 5.54 |
| 2026-10-09 12:00 | 17:52:21.38 | -22:15:39.9 | HIP 87458 | 6.28 |
| 2026-10-10 00:00 | 17:52:33.19 | -22:16:10.7 | HIP 87458 | 7.98 |
| 2026-10-10 12:00 | 17:52:45.13 | -22:16:41.5 | HIP 87458 | 10.18 |
| 2026-10-11 00:00 | 17:52:57.18 | -22:17:12.1 | HIP 87458 | 12.65 |