49P/Arend-Rigaux
Metadata
| Parameter | Value |
|---|---|
| Designation | 49P/Arend-Rigaux |
| Type | P |
| Perihelion (tp_cal, UTC) | 2011-10-19T07:09:47.998080Z |
| Orbit solution date (soln_date, UTC) | 2026-07-07T05:51:46Z |
| Obs used | 4486 |
| NEO | - |
| M1 | 13.900 |
| K1 | 6.500 |
| PC | - |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2015-02-02.0000000 |
| e | 0.60017016 |
| q (au) | 1.426129 |
| a (au) | 3.566839 |
| i (deg) | 19.056641 |
| Ω (om, deg) | 118.831084 |
| ω (w, deg) | 332.927303 |
| M (ma, deg) | 175.822888 |
Magnitude
Scatter + Global Linear
$$ M_a = (11.888 + 5.474\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 11.888 |
| n | 5.474 |
| gf | 0.983 |
| gb | -0.920 |
| k | 0.986 |
| 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 |
|---|---|---|---|
| 2023-05-02 | 2024-11-21 | +7.2269 | -1.762 |
| 2024-11-21 | 2024-08-28 | -0.4935 | +0.400 |
| 2024-08-28 | 2023-10-24 | -10.9208 | +4.536 |
| 2023-10-24 | 2026-03-18 | +46.5140 | -31.880 |
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 | 15:02:31.78 | -01:23:11.3 | HIP 73498 | 22.16 |
| 2026-09-20 12:00 | 15:02:55.49 | -01:26:17.5 | HIP 73498 | 28.78 |
| 2026-09-21 00:00 | 15:03:19.28 | -01:29:23.1 | HIP 73498 | 35.44 |
| 2026-09-21 12:00 | 15:03:43.15 | -01:32:28.3 | HIP 73852 | 31.36 |
| 2026-09-22 00:00 | 15:04:07.09 | -01:35:33.1 | HIP 73852 | 27.81 |
| 2026-09-22 12:00 | 15:04:31.12 | -01:38:37.3 | HIP 73852 | 25.55 |
| 2026-09-23 00:00 | 15:04:55.22 | -01:41:41.0 | HIP 73862 | 21.11 |
| 2026-09-23 12:00 | 15:05:19.39 | -01:44:44.2 | HIP 73862 | 15.53 |
| 2026-09-24 00:00 | 15:05:43.64 | -01:47:46.9 | HIP 73908 | 9.29 |
| 2026-09-24 12:00 | 15:06:07.96 | -01:50:49.1 | HIP 73908 | 2.51 |
| 2026-09-25 00:00 | 15:06:32.36 | -01:53:50.8 | HIP 73908 | 4.33 |
| 2026-09-25 12:00 | 15:06:56.83 | -01:56:52.0 | HIP 73908 | 11.14 |
| 2026-09-26 00:00 | 15:07:21.37 | -01:59:52.6 | HIP 73982 | 17.26 |
| 2026-09-26 12:00 | 15:07:45.99 | -02:02:52.8 | HIP 73982 | 16.80 |
| 2026-09-27 00:00 | 15:08:10.67 | -02:05:52.4 | HIP 73982 | 18.99 |
| 2026-09-27 12:00 | 15:08:35.42 | -02:08:51.5 | HIP 73982 | 23.11 |
| 2026-09-28 00:00 | 15:09:00.24 | -02:11:50.1 | HIP 73982 | 28.33 |
| 2026-09-28 12:00 | 15:09:25.13 | -02:14:48.1 | HIP 74338 | 32.47 |
| 2026-09-29 00:00 | 15:09:50.09 | -02:17:45.6 | HIP 74338 | 26.32 |
| 2026-09-29 12:00 | 15:10:15.12 | -02:20:42.6 | HIP 74338 | 20.62 |
| 2026-09-30 00:00 | 15:10:40.21 | -02:23:39.0 | HIP 74338 | 15.90 |
| 2026-09-30 12:00 | 15:11:05.37 | -02:26:34.9 | HIP 74338 | 13.26 |
| 2026-10-01 00:00 | 15:11:30.60 | -02:29:30.2 | HIP 74338 | 13.95 |
| 2026-10-01 12:00 | 15:11:55.89 | -02:32:25.0 | HIP 74338 | 17.60 |
| 2026-10-02 00:00 | 15:12:21.24 | -02:35:19.3 | HIP 74338 | 22.84 |
| 2026-10-02 12:00 | 15:12:46.66 | -02:38:13.0 | HIP 74554 | 22.48 |
| 2026-10-03 00:00 | 15:13:12.14 | -02:41:06.1 | HIP 74554 | 19.97 |
| 2026-10-03 12:00 | 15:13:37.68 | -02:43:58.6 | HIP 74554 | 19.74 |
| 2026-10-04 00:00 | 15:14:03.29 | -02:46:50.7 | HIP 74648 | 18.14 |
| 2026-10-04 12:00 | 15:14:28.96 | -02:49:42.1 | HIP 74648 | 11.14 |
| 2026-10-05 00:00 | 15:14:54.69 | -02:52:32.9 | HIP 74648 | 4.20 |
| 2026-10-05 12:00 | 15:15:20.47 | -02:55:23.2 | HIP 74648 | 3.16 |
| 2026-10-06 00:00 | 15:15:46.32 | -02:58:12.9 | HIP 74648 | 10.07 |
| 2026-10-06 12:00 | 15:16:12.23 | -03:01:02.0 | HIP 74648 | 17.10 |
| 2026-10-07 00:00 | 15:16:38.19 | -03:03:50.6 | HIP 74648 | 24.16 |
| 2026-10-07 12:00 | 15:17:04.22 | -03:06:38.5 | HIP 74871 | 24.44 |
| 2026-10-08 00:00 | 15:17:30.30 | -03:09:25.8 | HIP 74871 | 18.63 |
| 2026-10-08 12:00 | 15:17:56.43 | -03:12:12.6 | HIP 74871 | 14.06 |
| 2026-10-09 00:00 | 15:18:22.62 | -03:14:58.7 | HIP 74871 | 12.21 |
| 2026-10-09 12:00 | 15:18:48.87 | -03:17:44.2 | HIP 74871 | 14.20 |
| 2026-10-10 00:00 | 15:19:15.16 | -03:20:29.1 | HIP 74871 | 18.86 |
| 2026-10-10 12:00 | 15:19:41.52 | -03:23:13.4 | HIP 75089 | 16.38 |
| 2026-10-11 00:00 | 15:20:07.92 | -03:25:57.1 | HIP 75089 | 9.33 |