| Parameter |
Value |
| Designation |
181P/Shoemaker-Levy 6 |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2014-06-10T07:49:11.971200Z |
| Orbit solution date (soln_date, UTC) |
2014-08-29T13:06:38Z |
| Obs used |
88 |
| NEO |
Yes |
| M1 |
16.300 |
| K1 |
17.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2014-09-08.0000000 |
| e |
0.70732283 |
| q (au) |
1.123593 |
| a (au) |
3.839018 |
| i (deg) |
16.981179 |
| Ω (om, deg) |
37.679458 |
| ω (w, deg) |
333.798849 |
| M (ma, deg) |
11.750089 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.941 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.941 |
| n |
2.000 |
| gf |
0.901 |
| gb |
-0.500 |
| k |
0.861 |
| δ90 |
4.048 |
| 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 |
13:21:14.22 |
-01:24:48.2 |
HIP 65083 |
19.12 |
| 2026-03-26 12:00 |
13:20:59.01 |
-01:23:26.7 |
HIP 65083 |
18.11 |
| 2026-03-27 00:00 |
13:20:43.73 |
-01:22:05.0 |
HIP 65083 |
17.96 |
| 2026-03-27 12:00 |
13:20:28.40 |
-01:20:43.4 |
HIP 65083 |
18.71 |
| 2026-03-28 00:00 |
13:20:13.01 |
-01:19:21.8 |
HIP 64968 |
18.94 |
| 2026-03-28 12:00 |
13:19:57.56 |
-01:18:00.1 |
HIP 64968 |
14.92 |
| 2026-03-29 00:00 |
13:19:42.07 |
-01:16:38.5 |
HIP 64968 |
10.94 |
| 2026-03-29 12:00 |
13:19:26.52 |
-01:15:16.9 |
HIP 64968 |
7.10 |
| 2026-03-30 00:00 |
13:19:10.93 |
-01:13:55.4 |
HIP 64968 |
3.86 |
| 2026-03-30 12:00 |
13:18:55.28 |
-01:12:33.9 |
HIP 64968 |
3.68 |
| 2026-03-31 00:00 |
13:18:39.60 |
-01:11:12.4 |
HIP 64968 |
6.82 |
| 2026-03-31 12:00 |
13:18:23.87 |
-01:09:51.1 |
HIP 64968 |
10.68 |
| 2026-04-01 00:00 |
13:18:08.10 |
-01:08:29.8 |
HIP 64968 |
14.71 |
| 2026-04-01 12:00 |
13:17:52.29 |
-01:07:08.7 |
HIP 64968 |
18.81 |
| 2026-04-02 00:00 |
13:17:36.45 |
-01:05:47.6 |
HIP 64968 |
22.94 |
| 2026-04-02 12:00 |
13:17:20.57 |
-01:04:26.7 |
HIP 64769 |
23.45 |
| 2026-04-03 00:00 |
13:17:04.66 |
-01:03:05.9 |
HIP 64769 |
22.56 |
| 2026-04-03 12:00 |
13:16:48.72 |
-01:01:45.2 |
HIP 64769 |
22.44 |
| 2026-04-04 00:00 |
13:16:32.75 |
-01:00:24.8 |
HIP 64769 |
23.09 |
| 2026-04-04 12:00 |
13:16:16.75 |
-00:59:04.5 |
HIP 64769 |
24.45 |
| 2026-04-05 00:00 |
13:16:00.73 |
-00:57:44.3 |
HIP 64769 |
26.42 |
| 2026-04-05 12:00 |
13:15:44.69 |
-00:56:24.4 |
HIP 64769 |
28.88 |
| 2026-04-06 00:00 |
13:15:28.62 |
-00:55:04.7 |
HIP 64769 |
31.72 |
| 2026-04-06 12:00 |
13:15:12.54 |
-00:53:45.2 |
HIP 64769 |
34.83 |
| 2026-04-07 00:00 |
13:14:56.44 |
-00:52:25.9 |
HIP 64769 |
38.16 |
| 2026-04-07 12:00 |
13:14:40.32 |
-00:51:06.9 |
HIP 64571 |
36.74 |
| 2026-04-08 00:00 |
13:14:24.20 |
-00:49:48.1 |
HIP 64571 |
34.71 |
| 2026-04-08 12:00 |
13:14:08.06 |
-00:48:29.6 |
HIP 64571 |
33.11 |
| 2026-04-09 00:00 |
13:13:51.92 |
-00:47:11.4 |
HIP 64571 |
31.99 |
| 2026-04-09 12:00 |
13:13:35.77 |
-00:45:53.5 |
HIP 64571 |
31.42 |
| 2026-04-10 00:00 |
13:13:19.61 |
-00:44:35.9 |
HIP 64571 |
31.42 |
| 2026-04-10 12:00 |
13:13:03.46 |
-00:43:18.6 |
HIP 64571 |
31.99 |
| 2026-04-11 00:00 |
13:12:47.30 |
-00:42:01.6 |
HIP 64571 |
33.11 |
| 2026-04-11 12:00 |
13:12:31.15 |
-00:40:45.0 |
HIP 64298 |
31.19 |
| 2026-04-12 00:00 |
13:12:15.00 |
-00:39:28.7 |
HIP 64298 |
27.08 |
| 2026-04-12 12:00 |
13:11:58.85 |
-00:38:12.8 |
HIP 64298 |
23.01 |
| 2026-04-13 00:00 |
13:11:42.72 |
-00:36:57.3 |
HIP 64298 |
19.02 |
| 2026-04-13 12:00 |
13:11:26.60 |
-00:35:42.2 |
HIP 64298 |
15.16 |
| 2026-04-14 00:00 |
13:11:10.49 |
-00:34:27.5 |
HIP 64298 |
11.56 |
| 2026-04-14 12:00 |
13:10:54.39 |
-00:33:13.2 |
HIP 64298 |
8.57 |
| 2026-04-15 00:00 |
13:10:38.31 |
-00:31:59.3 |
HIP 64298 |
6.97 |
| 2026-04-15 12:00 |
13:10:22.26 |
-00:30:45.9 |
HIP 64298 |
7.69 |
| 2026-04-16 00:00 |
13:10:06.22 |
-00:29:32.9 |
HIP 64247 |
7.47 |