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) |
|---|---|---|---|---|
| 2026-07-29 00:00 | 17:49:11.65 | -20:52:56.7 | HIP 87235 | 4.78 |
| 2026-07-29 12:00 | 17:49:02.30 | -20:53:31.0 | HIP 87235 | 6.88 |
| 2026-07-30 00:00 | 17:48:53.08 | -20:54:05.4 | HIP 87235 | 9.03 |
| 2026-07-30 12:00 | 17:48:43.99 | -20:54:39.8 | HIP 87235 | 11.19 |
| 2026-07-31 00:00 | 17:48:35.03 | -20:55:14.2 | HIP 87235 | 13.33 |
| 2026-07-31 12:00 | 17:48:26.19 | -20:55:48.6 | HIP 87068 | 13.96 |
| 2026-08-01 00:00 | 17:48:17.49 | -20:56:23.1 | HIP 87068 | 12.40 |
| 2026-08-01 12:00 | 17:48:08.92 | -20:56:57.5 | HIP 87068 | 11.04 |
| 2026-08-02 00:00 | 17:48:00.48 | -20:57:32.0 | HIP 87068 | 9.97 |
| 2026-08-02 12:00 | 17:47:52.18 | -20:58:06.5 | HIP 87068 | 9.24 |
| 2026-08-03 00:00 | 17:47:44.01 | -20:58:41.0 | HIP 87064 | 7.89 |
| 2026-08-03 12:00 | 17:47:35.97 | -20:59:15.5 | HIP 87064 | 6.68 |
| 2026-08-04 00:00 | 17:47:28.07 | -20:59:50.1 | HIP 87064 | 5.88 |
| 2026-08-04 12:00 | 17:47:20.31 | -21:00:24.6 | HIP 87064 | 5.65 |
| 2026-08-05 00:00 | 17:47:12.69 | -21:00:59.2 | HIP 87064 | 6.02 |
| 2026-08-05 12:00 | 17:47:05.21 | -21:01:33.8 | HIP 87064 | 6.86 |
| 2026-08-06 00:00 | 17:46:57.87 | -21:02:08.4 | HIP 87064 | 8.02 |
| 2026-08-06 12:00 | 17:46:50.66 | -21:02:43.1 | HIP 87064 | 9.35 |
| 2026-08-07 00:00 | 17:46:43.60 | -21:03:17.7 | HIP 87064 | 10.78 |
| 2026-08-07 12:00 | 17:46:36.68 | -21:03:52.4 | HIP 87064 | 12.26 |
| 2026-08-08 00:00 | 17:46:29.91 | -21:04:27.1 | HIP 87064 | 13.75 |
| 2026-08-08 12:00 | 17:46:23.28 | -21:05:01.8 | HIP 87064 | 15.26 |
| 2026-08-09 00:00 | 17:46:16.80 | -21:05:36.5 | HIP 87064 | 16.75 |
| 2026-08-09 12:00 | 17:46:10.46 | -21:06:11.3 | HIP 87064 | 18.24 |
| 2026-08-10 00:00 | 17:46:04.26 | -21:06:46.1 | HIP 87060 | 19.57 |
| 2026-08-10 12:00 | 17:45:58.22 | -21:07:20.8 | HIP 87060 | 20.79 |
| 2026-08-11 00:00 | 17:45:52.32 | -21:07:55.6 | HIP 87060 | 22.02 |
| 2026-08-11 12:00 | 17:45:46.58 | -21:08:30.5 | HIP 87060 | 23.25 |
| 2026-08-12 00:00 | 17:45:40.98 | -21:09:05.3 | HIP 87060 | 24.46 |
| 2026-08-12 12:00 | 17:45:35.53 | -21:09:40.1 | HIP 87000 | 25.64 |
| 2026-08-13 00:00 | 17:45:30.24 | -21:10:15.0 | HIP 87000 | 25.93 |
| 2026-08-13 12:00 | 17:45:25.09 | -21:10:49.9 | HIP 87000 | 26.27 |
| 2026-08-14 00:00 | 17:45:20.10 | -21:11:24.8 | HIP 87000 | 26.65 |
| 2026-08-14 12:00 | 17:45:15.26 | -21:11:59.7 | HIP 87000 | 27.06 |
| 2026-08-15 00:00 | 17:45:10.57 | -21:12:34.6 | HIP 87000 | 27.49 |
| 2026-08-15 12:00 | 17:45:06.04 | -21:13:09.5 | HIP 87000 | 27.94 |
| 2026-08-16 00:00 | 17:45:01.66 | -21:13:44.5 | HIP 87000 | 28.41 |
| 2026-08-16 12:00 | 17:44:57.43 | -21:14:19.5 | HIP 87000 | 28.89 |
| 2026-08-17 00:00 | 17:44:53.36 | -21:14:54.4 | HIP 87000 | 29.37 |
| 2026-08-17 12:00 | 17:44:49.45 | -21:15:29.4 | HIP 87000 | 29.86 |
| 2026-08-18 00:00 | 17:44:45.69 | -21:16:04.4 | HIP 87000 | 30.34 |
| 2026-08-18 12:00 | 17:44:42.08 | -21:16:39.4 | HIP 86736 | 30.11 |
| 2026-08-19 00:00 | 17:44:38.63 | -21:17:14.4 | HIP 86736 | 29.16 |