| Parameter |
Value |
| Designation |
137P/Shoemaker-Levy 2 |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2018-12-14T01:43:47.254080Z |
| Orbit solution date (soln_date, UTC) |
2026-08-21T14:12:14Z |
| Obs used |
1233 |
| NEO |
- |
| M1 |
15.400 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2016-01-01.0000000 |
| e |
0.57204677 |
| q (au) |
1.933450 |
| a (au) |
4.517901 |
| i (deg) |
4.850290 |
| Ω (om, deg) |
233.073578 |
| ω (w, deg) |
140.984715 |
| M (ma, deg) |
249.351184 |
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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
15:14:17.88 |
-17:26:04.6 |
HIP 74568 |
5.19 |
| 2026-09-20 12:00 |
15:14:37.34 |
-17:27:13.4 |
HIP 74568 |
7.56 |
| 2026-09-21 00:00 |
15:14:56.93 |
-17:28:22.4 |
HIP 74568 |
11.56 |
| 2026-09-21 12:00 |
15:15:16.63 |
-17:29:31.9 |
HIP 74568 |
16.04 |
| 2026-09-22 00:00 |
15:15:36.45 |
-17:30:41.6 |
HIP 74568 |
20.71 |
| 2026-09-22 12:00 |
15:15:56.39 |
-17:31:51.6 |
HIP 74600 |
24.30 |
| 2026-09-23 00:00 |
15:16:16.44 |
-17:33:02.0 |
HIP 74600 |
27.74 |
| 2026-09-23 12:00 |
15:16:36.61 |
-17:34:12.6 |
HIP 74838 |
26.96 |
| 2026-09-24 00:00 |
15:16:56.90 |
-17:35:23.5 |
HIP 74838 |
25.68 |
| 2026-09-24 12:00 |
15:17:17.30 |
-17:36:34.7 |
HIP 74838 |
25.32 |
| 2026-09-25 00:00 |
15:17:37.82 |
-17:37:46.2 |
HIP 74838 |
25.95 |
| 2026-09-25 12:00 |
15:17:58.45 |
-17:38:58.0 |
HIP 74838 |
27.52 |
| 2026-09-26 00:00 |
15:18:19.19 |
-17:40:10.1 |
HIP 74838 |
29.88 |
| 2026-09-26 12:00 |
15:18:40.05 |
-17:41:22.4 |
HIP 74906 |
29.67 |
| 2026-09-27 00:00 |
15:19:01.01 |
-17:42:35.0 |
HIP 74906 |
29.30 |
| 2026-09-27 12:00 |
15:19:22.09 |
-17:43:47.8 |
HIP 74906 |
29.83 |
| 2026-09-28 00:00 |
15:19:43.28 |
-17:45:00.9 |
HIP 75110 |
29.67 |
| 2026-09-28 12:00 |
15:20:04.58 |
-17:46:14.2 |
HIP 75110 |
26.04 |
| 2026-09-29 00:00 |
15:20:25.98 |
-17:47:27.8 |
HIP 75110 |
23.01 |
| 2026-09-29 12:00 |
15:20:47.50 |
-17:48:41.6 |
HIP 75110 |
20.87 |
| 2026-09-30 00:00 |
15:21:09.12 |
-17:49:55.6 |
HIP 75110 |
19.92 |
| 2026-09-30 12:00 |
15:21:30.85 |
-17:51:09.9 |
HIP 75110 |
20.36 |
| 2026-10-01 00:00 |
15:21:52.69 |
-17:52:24.4 |
HIP 75110 |
22.12 |
| 2026-10-01 12:00 |
15:22:14.64 |
-17:53:39.1 |
HIP 75217 |
21.63 |
| 2026-10-02 00:00 |
15:22:36.69 |
-17:54:54.0 |
HIP 75217 |
21.10 |
| 2026-10-02 12:00 |
15:22:58.85 |
-17:56:09.2 |
HIP 75217 |
21.93 |
| 2026-10-03 00:00 |
15:23:21.11 |
-17:57:24.5 |
HIP 75217 |
24.01 |
| 2026-10-03 12:00 |
15:23:43.48 |
-17:58:40.0 |
HIP 75217 |
27.04 |
| 2026-10-04 00:00 |
15:24:05.95 |
-17:59:55.7 |
HIP 75217 |
30.78 |
| 2026-10-04 12:00 |
15:24:28.52 |
-18:01:11.6 |
HIP 75601 |
32.94 |
| 2026-10-05 00:00 |
15:24:51.20 |
-18:02:27.7 |
HIP 75601 |
27.63 |
| 2026-10-05 12:00 |
15:25:13.98 |
-18:03:44.0 |
HIP 75601 |
22.43 |
| 2026-10-06 00:00 |
15:25:36.86 |
-18:05:00.4 |
HIP 75601 |
17.41 |
| 2026-10-06 12:00 |
15:25:59.85 |
-18:06:17.0 |
HIP 75601 |
12.87 |
| 2026-10-07 00:00 |
15:26:22.93 |
-18:07:33.8 |
HIP 75601 |
9.52 |
| 2026-10-07 12:00 |
15:26:46.11 |
-18:08:50.7 |
HIP 75601 |
8.91 |
| 2026-10-08 00:00 |
15:27:09.39 |
-18:10:07.8 |
HIP 75601 |
11.50 |
| 2026-10-08 12:00 |
15:27:32.77 |
-18:11:25.0 |
HIP 75601 |
15.82 |
| 2026-10-09 00:00 |
15:27:56.25 |
-18:12:42.3 |
HIP 75601 |
20.83 |
| 2026-10-09 12:00 |
15:28:19.82 |
-18:13:59.8 |
HIP 75664 |
23.96 |
| 2026-10-10 00:00 |
15:28:43.50 |
-18:15:17.4 |
HIP 75664 |
26.02 |
| 2026-10-10 12:00 |
15:29:07.26 |
-18:16:35.1 |
HIP 75768 |
27.41 |
| 2026-10-11 00:00 |
15:29:31.12 |
-18:17:53.0 |
HIP 75768 |
27.93 |