C/2006 P1 (McNaught)
Metadata
| Parameter | Value |
|---|---|
| Designation | C/2006 P1 (McNaught) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2007-01-12T19:10:20.087040Z |
| Orbit solution date (soln_date, UTC) | 2021-04-15T23:30:59Z |
| Obs used | 331 |
| NEO | - |
| M1 | 5.400 |
| K1 | 20.750 |
| PC | 0.030 |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2006-11-26.0000000 |
| e | 1.00001882 |
| q (au) | 0.170736 |
| a (au) | -9074.061069 |
| i (deg) | 77.837001 |
| Ω (om, deg) | 267.414803 |
| ω (w, deg) | 155.974968 |
| M (ma, deg) | -0.000055 |
Magnitude
Scatter + Global Linear
$$ M_a = (6.650 + 5.259\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 6.650 |
| n | 5.259 |
| gf | 0.800 |
| gb | -0.500 |
| k | 1.000 |
| 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 |
|---|---|---|---|
| 2006-08-07 | 2006-10-09 | +16.8994 | -5.727 |
| 2006-10-09 | 2006-12-24 | +2.3930 | -1.220 |
| 2006-12-24 | 2007-01-09 | -3.1120 | -1.827 |
| 2007-01-09 | 2007-01-12 | -0.3863 | +0.233 |
| 2007-01-12 | 2007-07-11 | -2.7439 | -1.992 |
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 | 16:52:42.04 | -53:17:08.7 | HIP 82555 | 17.34 |
| 2026-09-20 12:00 | 16:52:43.19 | -53:16:47.6 | HIP 82555 | 17.02 |
| 2026-09-21 00:00 | 16:52:44.39 | -53:16:26.7 | HIP 82555 | 16.70 |
| 2026-09-21 12:00 | 16:52:45.63 | -53:16:05.8 | HIP 82555 | 16.38 |
| 2026-09-22 00:00 | 16:52:46.90 | -53:15:45.0 | HIP 82555 | 16.07 |
| 2026-09-22 12:00 | 16:52:48.22 | -53:15:24.3 | HIP 82555 | 15.77 |
| 2026-09-23 00:00 | 16:52:49.57 | -53:15:03.7 | HIP 82555 | 15.47 |
| 2026-09-23 12:00 | 16:52:50.96 | -53:14:43.2 | HIP 82555 | 15.19 |
| 2026-09-24 00:00 | 16:52:52.39 | -53:14:22.8 | HIP 82555 | 14.90 |
| 2026-09-24 12:00 | 16:52:53.86 | -53:14:02.5 | HIP 82555 | 14.63 |
| 2026-09-25 00:00 | 16:52:55.37 | -53:13:42.3 | HIP 82555 | 14.37 |
| 2026-09-25 12:00 | 16:52:56.91 | -53:13:22.1 | HIP 82555 | 14.12 |
| 2026-09-26 00:00 | 16:52:58.49 | -53:13:02.1 | HIP 82555 | 13.88 |
| 2026-09-26 12:00 | 16:53:00.11 | -53:12:42.2 | HIP 82555 | 13.65 |
| 2026-09-27 00:00 | 16:53:01.77 | -53:12:22.4 | HIP 82555 | 13.43 |
| 2026-09-27 12:00 | 16:53:03.46 | -53:12:02.6 | HIP 82555 | 13.23 |
| 2026-09-28 00:00 | 16:53:05.19 | -53:11:43.0 | HIP 82555 | 13.04 |
| 2026-09-28 12:00 | 16:53:06.96 | -53:11:23.5 | HIP 82555 | 12.86 |
| 2026-09-29 00:00 | 16:53:08.77 | -53:11:04.1 | HIP 82555 | 12.70 |
| 2026-09-29 12:00 | 16:53:10.61 | -53:10:44.8 | HIP 82555 | 12.56 |
| 2026-09-30 00:00 | 16:53:12.49 | -53:10:25.6 | HIP 82555 | 12.43 |
| 2026-09-30 12:00 | 16:53:14.40 | -53:10:06.5 | HIP 82555 | 12.33 |
| 2026-10-01 00:00 | 16:53:16.35 | -53:09:47.6 | HIP 82555 | 12.24 |
| 2026-10-01 12:00 | 16:53:18.34 | -53:09:28.7 | HIP 82555 | 12.17 |
| 2026-10-02 00:00 | 16:53:20.37 | -53:09:10.0 | HIP 82555 | 12.12 |
| 2026-10-02 12:00 | 16:53:22.43 | -53:08:51.3 | HIP 82555 | 12.09 |
| 2026-10-03 00:00 | 16:53:24.52 | -53:08:32.8 | HIP 82555 | 12.09 |
| 2026-10-03 12:00 | 16:53:26.66 | -53:08:14.4 | HIP 82555 | 12.10 |
| 2026-10-04 00:00 | 16:53:28.82 | -53:07:56.2 | HIP 82555 | 12.14 |
| 2026-10-04 12:00 | 16:53:31.03 | -53:07:38.0 | HIP 82555 | 12.19 |
| 2026-10-05 00:00 | 16:53:33.27 | -53:07:20.0 | HIP 82555 | 12.27 |
| 2026-10-05 12:00 | 16:53:35.54 | -53:07:02.0 | HIP 82555 | 12.37 |
| 2026-10-06 00:00 | 16:53:37.85 | -53:06:44.2 | HIP 82555 | 12.49 |
| 2026-10-06 12:00 | 16:53:40.20 | -53:06:26.6 | HIP 82555 | 12.64 |
| 2026-10-07 00:00 | 16:53:42.57 | -53:06:09.0 | HIP 82555 | 12.80 |
| 2026-10-07 12:00 | 16:53:44.99 | -53:05:51.6 | HIP 82555 | 12.98 |
| 2026-10-08 00:00 | 16:53:47.44 | -53:05:34.3 | HIP 82555 | 13.19 |
| 2026-10-08 12:00 | 16:53:49.92 | -53:05:17.1 | HIP 82555 | 13.41 |
| 2026-10-09 00:00 | 16:53:52.44 | -53:05:00.1 | HIP 82555 | 13.65 |
| 2026-10-09 12:00 | 16:53:54.99 | -53:04:43.2 | HIP 82555 | 13.91 |
| 2026-10-10 00:00 | 16:53:57.57 | -53:04:26.4 | HIP 82555 | 14.18 |
| 2026-10-10 12:00 | 16:54:00.19 | -53:04:09.8 | HIP 82555 | 14.47 |
| 2026-10-11 00:00 | 16:54:02.84 | -53:03:53.3 | HIP 82555 | 14.78 |