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
$$ M_a = (7.292 + 4.602\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 7.292 |
| n | 4.602 |
| 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 | -2.0781 | +0.678 |
| 2002-01-22 | 2002-02-04 | -39.9944 | -10.010 |
| 2002-02-04 | 2002-05-18 | +3.0549 | -0.945 |
| 2002-05-18 | 2003-06-05 | +0.1428 | +0.246 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) | RA (J2000) | Dec (J2000) | Nearest HIP | Dist from HIP (arcmin) |
|---|---|---|---|---|
| 2026-09-20 00:00 | 19:06:35.94 | +51:05:14.3 | HIP 93943 | 13.16 |
| 2026-09-20 12:00 | 19:06:34.83 | +51:04:40.0 | HIP 93943 | 12.95 |
| 2026-09-21 00:00 | 19:06:33.76 | +51:04:05.6 | HIP 93943 | 12.77 |
| 2026-09-21 12:00 | 19:06:32.71 | +51:03:31.2 | HIP 93943 | 12.60 |
| 2026-09-22 00:00 | 19:06:31.70 | +51:02:56.7 | HIP 93943 | 12.45 |
| 2026-09-22 12:00 | 19:06:30.72 | +51:02:22.1 | HIP 93943 | 12.33 |
| 2026-09-23 00:00 | 19:06:29.78 | +51:01:47.5 | HIP 93943 | 12.23 |
| 2026-09-23 12:00 | 19:06:28.87 | +51:01:12.8 | HIP 93943 | 12.15 |
| 2026-09-24 00:00 | 19:06:27.99 | +51:00:38.0 | HIP 93943 | 12.10 |
| 2026-09-24 12:00 | 19:06:27.15 | +51:00:03.1 | HIP 93943 | 12.07 |
| 2026-09-25 00:00 | 19:06:26.34 | +50:59:28.2 | HIP 93943 | 12.06 |
| 2026-09-25 12:00 | 19:06:25.56 | +50:58:53.3 | HIP 93943 | 12.08 |
| 2026-09-26 00:00 | 19:06:24.81 | +50:58:18.3 | HIP 93943 | 12.12 |
| 2026-09-26 12:00 | 19:06:24.10 | +50:57:43.2 | HIP 93943 | 12.19 |
| 2026-09-27 00:00 | 19:06:23.42 | +50:57:08.1 | HIP 93943 | 12.28 |
| 2026-09-27 12:00 | 19:06:22.78 | +50:56:32.9 | HIP 93943 | 12.39 |
| 2026-09-28 00:00 | 19:06:22.17 | +50:55:57.7 | HIP 93943 | 12.52 |
| 2026-09-28 12:00 | 19:06:21.59 | +50:55:22.5 | HIP 93943 | 12.68 |
| 2026-09-29 00:00 | 19:06:21.05 | +50:54:47.2 | HIP 93943 | 12.85 |
| 2026-09-29 12:00 | 19:06:20.54 | +50:54:11.8 | HIP 93943 | 13.05 |
| 2026-09-30 00:00 | 19:06:20.06 | +50:53:36.5 | HIP 93943 | 13.26 |
| 2026-09-30 12:00 | 19:06:19.62 | +50:53:01.1 | HIP 93943 | 13.50 |
| 2026-10-01 00:00 | 19:06:19.21 | +50:52:25.7 | HIP 93943 | 13.75 |
| 2026-10-01 12:00 | 19:06:18.84 | +50:51:50.2 | HIP 93943 | 14.01 |
| 2026-10-02 00:00 | 19:06:18.49 | +50:51:14.7 | HIP 93943 | 14.29 |
| 2026-10-02 12:00 | 19:06:18.19 | +50:50:39.3 | HIP 93943 | 14.59 |
| 2026-10-03 00:00 | 19:06:17.91 | +50:50:03.7 | HIP 93943 | 14.89 |
| 2026-10-03 12:00 | 19:06:17.67 | +50:49:28.2 | HIP 93943 | 15.21 |
| 2026-10-04 00:00 | 19:06:17.47 | +50:48:52.7 | HIP 93943 | 15.55 |
| 2026-10-04 12:00 | 19:06:17.29 | +50:48:17.1 | HIP 93943 | 15.89 |
| 2026-10-05 00:00 | 19:06:17.16 | +50:47:41.5 | HIP 93943 | 16.24 |
| 2026-10-05 12:00 | 19:06:17.05 | +50:47:06.0 | HIP 93943 | 16.60 |
| 2026-10-06 00:00 | 19:06:16.98 | +50:46:30.4 | HIP 93943 | 16.97 |
| 2026-10-06 12:00 | 19:06:16.95 | +50:45:54.8 | HIP 93943 | 17.35 |
| 2026-10-07 00:00 | 19:06:16.94 | +50:45:19.2 | HIP 93943 | 17.74 |
| 2026-10-07 12:00 | 19:06:16.98 | +50:44:43.7 | HIP 93943 | 18.14 |
| 2026-10-08 00:00 | 19:06:17.04 | +50:44:08.1 | HIP 93943 | 18.54 |
| 2026-10-08 12:00 | 19:06:17.14 | +50:43:32.6 | HIP 93943 | 18.94 |
| 2026-10-09 00:00 | 19:06:17.28 | +50:42:57.0 | HIP 93943 | 19.36 |
| 2026-10-09 12:00 | 19:06:17.45 | +50:42:21.5 | HIP 93943 | 19.77 |
| 2026-10-10 00:00 | 19:06:17.65 | +50:41:46.0 | HIP 93943 | 20.20 |
| 2026-10-10 12:00 | 19:06:17.89 | +50:41:10.5 | HIP 93943 | 20.62 |
| 2026-10-11 00:00 | 19:06:18.16 | +50:40:35.1 | HIP 93943 | 21.06 |