| 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) |
| 2026-06-01 00:00 |
07:45:00.84 |
+21:12:33.1 |
HIP 37909 |
16.49 |
| 2026-06-01 12:00 |
07:45:25.06 |
+21:11:55.9 |
HIP 37909 |
11.01 |
| 2026-06-02 00:00 |
07:45:49.35 |
+21:11:18.3 |
HIP 37909 |
5.89 |
| 2026-06-02 12:00 |
07:46:13.73 |
+21:10:40.3 |
HIP 37909 |
3.61 |
| 2026-06-03 00:00 |
07:46:38.18 |
+21:10:01.8 |
HIP 37909 |
7.55 |
| 2026-06-03 12:00 |
07:47:02.70 |
+21:09:22.8 |
HIP 37909 |
12.94 |
| 2026-06-04 00:00 |
07:47:27.31 |
+21:08:43.4 |
HIP 38046 |
9.40 |
| 2026-06-04 12:00 |
07:47:51.98 |
+21:08:03.4 |
HIP 38046 |
6.03 |
| 2026-06-05 00:00 |
07:48:16.73 |
+21:07:23.1 |
HIP 38046 |
7.18 |
| 2026-06-05 12:00 |
07:48:41.56 |
+21:06:42.3 |
HIP 38046 |
11.61 |
| 2026-06-06 00:00 |
07:49:06.45 |
+21:06:01.0 |
HIP 38046 |
16.92 |
| 2026-06-06 12:00 |
07:49:31.42 |
+21:05:19.2 |
HIP 38046 |
22.52 |
| 2026-06-07 00:00 |
07:49:56.46 |
+21:04:37.0 |
HIP 38352 |
24.04 |
| 2026-06-07 12:00 |
07:50:21.57 |
+21:03:54.3 |
HIP 38352 |
19.15 |
| 2026-06-08 00:00 |
07:50:46.74 |
+21:03:11.2 |
HIP 38352 |
14.99 |
| 2026-06-08 12:00 |
07:51:11.99 |
+21:02:27.6 |
HIP 38352 |
12.35 |
| 2026-06-09 00:00 |
07:51:37.30 |
+21:01:43.6 |
HIP 38352 |
12.29 |
| 2026-06-09 12:00 |
07:52:02.68 |
+21:00:59.1 |
HIP 38352 |
14.85 |
| 2026-06-10 00:00 |
07:52:28.13 |
+21:00:14.1 |
HIP 38528 |
16.28 |
| 2026-06-10 12:00 |
07:52:53.64 |
+20:59:28.7 |
HIP 38528 |
11.53 |
| 2026-06-11 00:00 |
07:53:19.22 |
+20:58:42.8 |
HIP 38528 |
8.53 |
| 2026-06-11 12:00 |
07:53:44.86 |
+20:57:56.5 |
HIP 38529 |
9.11 |
| 2026-06-12 00:00 |
07:54:10.56 |
+20:57:09.7 |
HIP 38601 |
9.18 |
| 2026-06-12 12:00 |
07:54:36.32 |
+20:56:22.5 |
HIP 38601 |
11.30 |
| 2026-06-13 00:00 |
07:55:02.15 |
+20:55:34.8 |
HIP 38601 |
15.66 |
| 2026-06-13 12:00 |
07:55:28.04 |
+20:54:46.6 |
HIP 38777 |
12.39 |
| 2026-06-14 00:00 |
07:55:53.99 |
+20:53:58.0 |
HIP 38777 |
6.96 |
| 2026-06-14 12:00 |
07:56:19.99 |
+20:53:09.0 |
HIP 38777 |
4.26 |
| 2026-06-15 00:00 |
07:56:46.06 |
+20:52:19.5 |
HIP 38856 |
7.32 |
| 2026-06-15 12:00 |
07:57:12.18 |
+20:51:29.6 |
HIP 38856 |
6.69 |
| 2026-06-16 00:00 |
07:57:38.36 |
+20:50:39.2 |
HIP 38856 |
10.59 |
| 2026-06-16 12:00 |
07:58:04.59 |
+20:49:48.4 |
HIP 38856 |
16.00 |
| 2026-06-17 00:00 |
07:58:30.88 |
+20:48:57.1 |
HIP 39064 |
14.81 |
| 2026-06-17 12:00 |
07:58:57.22 |
+20:48:05.4 |
HIP 39064 |
8.95 |
| 2026-06-18 00:00 |
07:59:23.61 |
+20:47:13.2 |
HIP 39064 |
4.23 |
| 2026-06-18 12:00 |
07:59:50.05 |
+20:46:20.6 |
HIP 39064 |
5.79 |
| 2026-06-19 00:00 |
08:00:16.55 |
+20:45:27.6 |
HIP 39064 |
11.28 |
| 2026-06-19 12:00 |
08:00:43.09 |
+20:44:34.2 |
HIP 39064 |
17.32 |
| 2026-06-20 00:00 |
08:01:09.69 |
+20:43:40.3 |
HIP 39260 |
18.49 |
| 2026-06-20 12:00 |
08:01:36.33 |
+20:42:46.0 |
HIP 39260 |
15.99 |
| 2026-06-21 00:00 |
08:02:03.02 |
+20:41:51.3 |
HIP 39260 |
15.78 |
| 2026-06-21 12:00 |
08:02:29.76 |
+20:40:56.1 |
HIP 39260 |
17.94 |
| 2026-06-22 00:00 |
08:02:56.54 |
+20:40:00.5 |
HIP 39428 |
21.57 |