C/2000 WM1 (LINEAR)
Metadata
| Parameter | Value |
|---|---|
| Designation | C/2000 WM1 (LINEAR) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2002-01-22T16:09:23.857920Z |
| Orbit solution date (soln_date, UTC) | 2021-04-15T23:30:08Z |
| Obs used | 2130 |
| NEO | - |
| M1 | 11.200 |
| K1 | 4.750 |
| PC | - |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2002-01-24.0000000 |
| e | 1.00024278 |
| q (au) | 0.555348 |
| a (au) | -2287.433616 |
| i (deg) | 72.550229 |
| Ω (om, deg) | 237.895729 |
| ω (w, deg) | 276.770906 |
| M (ma, deg) | 0.000012 |
Magnitude
Scatter + Global Linear
$$ M_a = (7.292 + 4.603\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 7.292 |
| n | 4.603 |
| gf | 0.800 |
| gb | -0.500 |
| k | 0.800 |
| δ90 | 1.000 |
| 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 |
|---|---|---|---|
| 2000-12-22 | 2002-01-22 | -2.0803 | +0.679 |
| 2002-01-22 | 2002-02-04 | -40.7720 | -10.195 |
| 2002-02-04 | 2002-06-20 | +3.2210 | -0.942 |
| 2002-06-20 | 2002-07-26 | -7.7856 | +3.852 |
| 2002-07-26 | 2003-06-05 | +0.8114 | -0.125 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) | RA (J2000) | Dec (J2000) | Nearest HIP | Dist from HIP (arcmin) |
|---|---|---|---|---|
| 2026-02-03 00:00 | 19:16:42.59 | +49:38:52.7 | HIP 94798 | 13.46 |
| 2026-02-03 12:00 | 19:16:46.19 | +49:39:10.8 | HIP 94798 | 12.94 |
| 2026-02-04 00:00 | 19:16:49.78 | +49:39:29.2 | HIP 94798 | 12.43 |
| 2026-02-04 12:00 | 19:16:53.35 | +49:39:47.8 | HIP 94798 | 11.94 |
| 2026-02-05 00:00 | 19:16:56.90 | +49:40:06.7 | HIP 94798 | 11.45 |
| 2026-02-05 12:00 | 19:17:00.45 | +49:40:25.9 | HIP 94798 | 10.98 |
| 2026-02-06 00:00 | 19:17:03.97 | +49:40:45.3 | HIP 94798 | 10.53 |
| 2026-02-06 12:00 | 19:17:07.48 | +49:41:05.0 | HIP 94798 | 10.10 |
| 2026-02-07 00:00 | 19:17:10.97 | +49:41:25.0 | HIP 94798 | 9.68 |
| 2026-02-07 12:00 | 19:17:14.45 | +49:41:45.2 | HIP 94798 | 9.29 |
| 2026-02-08 00:00 | 19:17:17.91 | +49:42:05.7 | HIP 94798 | 8.93 |
| 2026-02-08 12:00 | 19:17:21.35 | +49:42:26.5 | HIP 94798 | 8.59 |
| 2026-02-09 00:00 | 19:17:24.78 | +49:42:47.5 | HIP 94798 | 8.29 |
| 2026-02-09 12:00 | 19:17:28.19 | +49:43:08.7 | HIP 94798 | 8.03 |
| 2026-02-10 00:00 | 19:17:31.58 | +49:43:30.2 | HIP 94798 | 7.81 |
| 2026-02-10 12:00 | 19:17:34.95 | +49:43:52.0 | HIP 94798 | 7.63 |
| 2026-02-11 00:00 | 19:17:38.31 | +49:44:14.1 | HIP 94798 | 7.51 |
| 2026-02-11 12:00 | 19:17:41.64 | +49:44:36.3 | HIP 94798 | 7.43 |
| 2026-02-12 00:00 | 19:17:44.96 | +49:44:58.9 | HIP 94798 | 7.40 |
| 2026-02-12 12:00 | 19:17:48.26 | +49:45:21.6 | HIP 94798 | 7.43 |
| 2026-02-13 00:00 | 19:17:51.54 | +49:45:44.7 | HIP 94798 | 7.51 |
| 2026-02-13 12:00 | 19:17:54.80 | +49:46:07.9 | HIP 94798 | 7.63 |
| 2026-02-14 00:00 | 19:17:58.04 | +49:46:31.4 | HIP 94798 | 7.81 |
| 2026-02-14 12:00 | 19:18:01.26 | +49:46:55.2 | HIP 94798 | 8.03 |
| 2026-02-15 00:00 | 19:18:04.47 | +49:47:19.2 | HIP 94798 | 8.29 |
| 2026-02-15 12:00 | 19:18:07.65 | +49:47:43.4 | HIP 94798 | 8.59 |
| 2026-02-16 00:00 | 19:18:10.81 | +49:48:07.9 | HIP 94922 | 8.15 |
| 2026-02-16 12:00 | 19:18:13.94 | +49:48:32.6 | HIP 94922 | 7.51 |
| 2026-02-17 00:00 | 19:18:17.06 | +49:48:57.5 | HIP 94922 | 6.89 |
| 2026-02-17 12:00 | 19:18:20.16 | +49:49:22.7 | HIP 94922 | 6.27 |
| 2026-02-18 00:00 | 19:18:23.23 | +49:49:48.1 | HIP 94922 | 5.66 |
| 2026-02-18 12:00 | 19:18:26.29 | +49:50:13.7 | HIP 94922 | 5.06 |
| 2026-02-19 00:00 | 19:18:29.32 | +49:50:39.5 | HIP 94922 | 4.48 |
| 2026-02-19 12:00 | 19:18:32.33 | +49:51:05.6 | HIP 94922 | 3.93 |
| 2026-02-20 00:00 | 19:18:35.31 | +49:51:31.9 | HIP 94922 | 3.42 |
| 2026-02-20 12:00 | 19:18:38.28 | +49:51:58.4 | HIP 94922 | 2.97 |
| 2026-02-21 00:00 | 19:18:41.22 | +49:52:25.1 | HIP 94922 | 2.60 |
| 2026-02-21 12:00 | 19:18:44.14 | +49:52:52.1 | HIP 94922 | 2.37 |
| 2026-02-22 00:00 | 19:18:47.03 | +49:53:19.2 | HIP 94922 | 2.31 |
| 2026-02-22 12:00 | 19:18:49.90 | +49:53:46.6 | HIP 94922 | 2.43 |
| 2026-02-23 00:00 | 19:18:52.75 | +49:54:14.1 | HIP 94922 | 2.71 |
| 2026-02-23 12:00 | 19:18:55.57 | +49:54:41.9 | HIP 94922 | 3.11 |
| 2026-02-24 00:00 | 19:18:58.37 | +49:55:09.9 | HIP 94922 | 3.58 |