| Parameter |
Value |
| Designation |
C/2011 L2 (McNaught) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2011-11-01T06:33:18.060480Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:51Z |
| Obs used |
57 |
| NEO |
- |
| M1 |
11.800 |
| K1 |
13.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2011-09-08.0000000 |
| e |
1.00177257 |
| q (au) |
1.943449 |
| a (au) |
-1096.399619 |
| i (deg) |
104.257426 |
| Ω (om, deg) |
131.347725 |
| ω (w, deg) |
257.028128 |
| M (ma, deg) |
-0.001473 |
Magnitude
Scatter + Global Linear
$$
M_a = (18.228 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
18.228 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.800 |
| δ90 |
10.000 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
08:53:20.59 |
+66:37:02.2 |
HIP 43523 |
13.43 |
| 2026-03-26 12:00 |
08:53:15.17 |
+66:36:37.0 |
HIP 43523 |
12.76 |
| 2026-03-27 00:00 |
08:53:09.83 |
+66:36:11.5 |
HIP 43523 |
12.09 |
| 2026-03-27 12:00 |
08:53:04.55 |
+66:35:45.7 |
HIP 43523 |
11.42 |
| 2026-03-28 00:00 |
08:52:59.35 |
+66:35:19.6 |
HIP 43523 |
10.76 |
| 2026-03-28 12:00 |
08:52:54.21 |
+66:34:53.2 |
HIP 43523 |
10.10 |
| 2026-03-29 00:00 |
08:52:49.15 |
+66:34:26.6 |
HIP 43523 |
9.44 |
| 2026-03-29 12:00 |
08:52:44.16 |
+66:33:59.7 |
HIP 43523 |
8.78 |
| 2026-03-30 00:00 |
08:52:39.25 |
+66:33:32.5 |
HIP 43523 |
8.13 |
| 2026-03-30 12:00 |
08:52:34.40 |
+66:33:05.1 |
HIP 43523 |
7.48 |
| 2026-03-31 00:00 |
08:52:29.63 |
+66:32:37.4 |
HIP 43523 |
6.83 |
| 2026-03-31 12:00 |
08:52:24.93 |
+66:32:09.5 |
HIP 43523 |
6.19 |
| 2026-04-01 00:00 |
08:52:20.31 |
+66:31:41.3 |
HIP 43523 |
5.55 |
| 2026-04-01 12:00 |
08:52:15.75 |
+66:31:12.8 |
HIP 43523 |
4.91 |
| 2026-04-02 00:00 |
08:52:11.27 |
+66:30:44.1 |
HIP 43523 |
4.28 |
| 2026-04-02 12:00 |
08:52:06.87 |
+66:30:15.2 |
HIP 43523 |
3.65 |
| 2026-04-03 00:00 |
08:52:02.54 |
+66:29:46.0 |
HIP 43523 |
3.04 |
| 2026-04-03 12:00 |
08:51:58.28 |
+66:29:16.6 |
HIP 43523 |
2.44 |
| 2026-04-04 00:00 |
08:51:54.09 |
+66:28:47.0 |
HIP 43523 |
1.87 |
| 2026-04-04 12:00 |
08:51:49.98 |
+66:28:17.1 |
HIP 43523 |
1.38 |
| 2026-04-05 00:00 |
08:51:45.95 |
+66:27:47.0 |
HIP 43523 |
1.05 |
| 2026-04-05 12:00 |
08:51:41.99 |
+66:27:16.6 |
HIP 43523 |
1.05 |
| 2026-04-06 00:00 |
08:51:38.10 |
+66:26:46.0 |
HIP 43523 |
1.39 |
| 2026-04-06 12:00 |
08:51:34.29 |
+66:26:15.2 |
HIP 43523 |
1.88 |
| 2026-04-07 00:00 |
08:51:30.56 |
+66:25:44.2 |
HIP 43523 |
2.44 |
| 2026-04-07 12:00 |
08:51:26.90 |
+66:25:13.0 |
HIP 43523 |
3.02 |
| 2026-04-08 00:00 |
08:51:23.32 |
+66:24:41.6 |
HIP 43523 |
3.62 |
| 2026-04-08 12:00 |
08:51:19.81 |
+66:24:09.9 |
HIP 43523 |
4.23 |
| 2026-04-09 00:00 |
08:51:16.38 |
+66:23:38.1 |
HIP 43523 |
4.84 |
| 2026-04-09 12:00 |
08:51:13.02 |
+66:23:06.0 |
HIP 43523 |
5.45 |
| 2026-04-10 00:00 |
08:51:09.74 |
+66:22:33.8 |
HIP 43523 |
6.06 |
| 2026-04-10 12:00 |
08:51:06.54 |
+66:22:01.3 |
HIP 43523 |
6.68 |
| 2026-04-11 00:00 |
08:51:03.41 |
+66:21:28.7 |
HIP 43523 |
7.29 |
| 2026-04-11 12:00 |
08:51:00.36 |
+66:20:55.8 |
HIP 43523 |
7.91 |
| 2026-04-12 00:00 |
08:50:57.39 |
+66:20:22.8 |
HIP 43523 |
8.52 |
| 2026-04-12 12:00 |
08:50:54.49 |
+66:19:49.6 |
HIP 43523 |
9.13 |
| 2026-04-13 00:00 |
08:50:51.67 |
+66:19:16.2 |
HIP 43523 |
9.74 |
| 2026-04-13 12:00 |
08:50:48.93 |
+66:18:42.6 |
HIP 43523 |
10.35 |
| 2026-04-14 00:00 |
08:50:46.26 |
+66:18:08.8 |
HIP 43523 |
10.96 |
| 2026-04-14 12:00 |
08:50:43.67 |
+66:17:34.9 |
HIP 43523 |
11.57 |
| 2026-04-15 00:00 |
08:50:41.16 |
+66:17:00.8 |
HIP 43534 |
12.13 |
| 2026-04-15 12:00 |
08:50:38.73 |
+66:16:26.6 |
HIP 43534 |
11.87 |
| 2026-04-16 00:00 |
08:50:36.37 |
+66:15:52.1 |
HIP 43534 |
11.64 |