| Parameter |
Value |
| Designation |
P/2005 L1 (McNaught) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2005-12-13T02:11:41.599680Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:50Z |
| Obs used |
257 |
| NEO |
- |
| M1 |
10.300 |
| K1 |
10.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2005-07-03.0000000 |
| e |
0.20923826 |
| q (au) |
3.142854 |
| a (au) |
3.974464 |
| i (deg) |
7.736935 |
| Ω (om, deg) |
138.329197 |
| ω (w, deg) |
149.558655 |
| M (ma, deg) |
339.713017 |
Magnitude
Scatter + Global Linear
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
07:09:32.64 |
+21:24:08.9 |
HIP 34608 |
12.21 |
| 2026-03-26 12:00 |
07:09:37.21 |
+21:24:34.8 |
HIP 34608 |
11.89 |
| 2026-03-27 00:00 |
07:09:41.99 |
+21:25:00.3 |
HIP 34608 |
11.65 |
| 2026-03-27 12:00 |
07:09:46.99 |
+21:25:25.3 |
HIP 34608 |
11.50 |
| 2026-03-28 00:00 |
07:09:52.20 |
+21:25:49.8 |
HIP 34608 |
11.46 |
| 2026-03-28 12:00 |
07:09:57.62 |
+21:26:13.9 |
HIP 34608 |
11.54 |
| 2026-03-29 00:00 |
07:10:03.25 |
+21:26:37.5 |
HIP 34608 |
11.76 |
| 2026-03-29 12:00 |
07:10:09.09 |
+21:27:00.6 |
HIP 34608 |
12.13 |
| 2026-03-30 00:00 |
07:10:15.14 |
+21:27:23.3 |
HIP 34608 |
12.65 |
| 2026-03-30 12:00 |
07:10:21.40 |
+21:27:45.5 |
HIP 34690 |
11.19 |
| 2026-03-31 00:00 |
07:10:27.86 |
+21:28:07.3 |
HIP 34690 |
9.66 |
| 2026-03-31 12:00 |
07:10:34.53 |
+21:28:28.6 |
HIP 34690 |
8.11 |
| 2026-04-01 00:00 |
07:10:41.40 |
+21:28:49.4 |
HIP 34690 |
6.53 |
| 2026-04-01 12:00 |
07:10:48.48 |
+21:29:09.8 |
HIP 34690 |
4.95 |
| 2026-04-02 00:00 |
07:10:55.76 |
+21:29:29.8 |
HIP 34690 |
3.45 |
| 2026-04-02 12:00 |
07:11:03.24 |
+21:29:49.2 |
HIP 34690 |
2.28 |
| 2026-04-03 00:00 |
07:11:10.92 |
+21:30:08.2 |
HIP 34690 |
2.22 |
| 2026-04-03 12:00 |
07:11:18.80 |
+21:30:26.8 |
HIP 34690 |
3.39 |
| 2026-04-04 00:00 |
07:11:26.89 |
+21:30:44.9 |
HIP 34690 |
5.05 |
| 2026-04-04 12:00 |
07:11:35.16 |
+21:31:02.5 |
HIP 34690 |
6.88 |
| 2026-04-05 00:00 |
07:11:43.64 |
+21:31:19.7 |
HIP 34690 |
8.81 |
| 2026-04-05 12:00 |
07:11:52.31 |
+21:31:36.5 |
HIP 34690 |
10.81 |
| 2026-04-06 00:00 |
07:12:01.18 |
+21:31:52.7 |
HIP 34690 |
12.86 |
| 2026-04-06 12:00 |
07:12:10.25 |
+21:32:08.5 |
HIP 34856 |
13.83 |
| 2026-04-07 00:00 |
07:12:19.50 |
+21:32:23.9 |
HIP 34856 |
12.86 |
| 2026-04-07 12:00 |
07:12:28.95 |
+21:32:38.8 |
HIP 34856 |
12.18 |
| 2026-04-08 00:00 |
07:12:38.59 |
+21:32:53.2 |
HIP 34856 |
11.87 |
| 2026-04-08 12:00 |
07:12:48.42 |
+21:33:07.1 |
HIP 34856 |
11.97 |
| 2026-04-09 00:00 |
07:12:58.45 |
+21:33:20.7 |
HIP 34856 |
12.51 |
| 2026-04-09 12:00 |
07:13:08.66 |
+21:33:33.7 |
HIP 34856 |
13.45 |
| 2026-04-10 00:00 |
07:13:19.06 |
+21:33:46.3 |
HIP 34856 |
14.74 |
| 2026-04-10 12:00 |
07:13:29.64 |
+21:33:58.4 |
HIP 34856 |
16.31 |
| 2026-04-11 00:00 |
07:13:40.41 |
+21:34:10.0 |
HIP 34856 |
18.10 |
| 2026-04-11 12:00 |
07:13:51.37 |
+21:34:21.2 |
HIP 34856 |
20.08 |
| 2026-04-12 00:00 |
07:14:02.51 |
+21:34:31.9 |
HIP 34856 |
22.21 |
| 2026-04-12 12:00 |
07:14:13.84 |
+21:34:42.2 |
HIP 34856 |
24.46 |
| 2026-04-13 00:00 |
07:14:25.34 |
+21:34:52.0 |
HIP 34856 |
26.81 |
| 2026-04-13 12:00 |
07:14:37.03 |
+21:35:01.3 |
HIP 35106 |
26.48 |
| 2026-04-14 00:00 |
07:14:48.90 |
+21:35:10.2 |
HIP 35106 |
25.09 |
| 2026-04-14 12:00 |
07:15:00.95 |
+21:35:18.5 |
HIP 35106 |
23.93 |
| 2026-04-15 00:00 |
07:15:13.18 |
+21:35:26.5 |
HIP 35106 |
23.06 |
| 2026-04-15 12:00 |
07:15:25.58 |
+21:35:33.9 |
HIP 35106 |
22.51 |
| 2026-04-16 00:00 |
07:15:38.16 |
+21:35:40.9 |
HIP 35106 |
22.34 |