| Parameter |
Value |
| Designation |
135P/Shoemaker-Levy 8 |
| Type |
P |
| Perihelion (tp_cal, UTC) |
1999-12-10T12:02:32.936640Z |
| Orbit solution date (soln_date, UTC) |
2024-03-14T08:42:34Z |
| Obs used |
115 |
| NEO |
- |
| M1 |
7.000 |
| K1 |
17.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1997-02-21.0000000 |
| e |
0.29022851 |
| q (au) |
2.716890 |
| a (au) |
3.827837 |
| i (deg) |
6.050581 |
| Ω (om, deg) |
213.361982 |
| ω (w, deg) |
22.698035 |
| M (ma, deg) |
225.433199 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.084 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.084 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
1.000 |
| 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) |
| 2026-05-12 00:00 |
04:08:28.27 |
+18:08:57.2 |
HIP 19470 |
31.37 |
| 2026-05-12 12:00 |
04:08:56.39 |
+18:10:05.8 |
HIP 19470 |
25.65 |
| 2026-05-13 00:00 |
04:09:24.53 |
+18:11:14.1 |
HIP 19470 |
20.56 |
| 2026-05-13 12:00 |
04:09:52.71 |
+18:12:22.1 |
HIP 19470 |
16.73 |
| 2026-05-14 00:00 |
04:10:20.91 |
+18:13:29.8 |
HIP 19504 |
12.94 |
| 2026-05-14 12:00 |
04:10:49.15 |
+18:14:37.2 |
HIP 19549 |
9.97 |
| 2026-05-15 00:00 |
04:11:17.41 |
+18:15:44.2 |
HIP 19549 |
7.15 |
| 2026-05-15 12:00 |
04:11:45.70 |
+18:16:51.0 |
HIP 19549 |
9.77 |
| 2026-05-16 00:00 |
04:12:14.02 |
+18:17:57.4 |
HIP 19549 |
15.25 |
| 2026-05-16 12:00 |
04:12:42.36 |
+18:19:03.4 |
HIP 19549 |
21.51 |
| 2026-05-17 00:00 |
04:13:10.73 |
+18:20:09.2 |
HIP 19549 |
28.04 |
| 2026-05-17 12:00 |
04:13:39.12 |
+18:21:14.6 |
HIP 19847 |
28.43 |
| 2026-05-18 00:00 |
04:14:07.54 |
+18:22:19.6 |
HIP 19847 |
22.48 |
| 2026-05-18 12:00 |
04:14:35.98 |
+18:23:24.3 |
HIP 19847 |
17.20 |
| 2026-05-19 00:00 |
04:15:04.44 |
+18:24:28.7 |
HIP 19847 |
13.40 |
| 2026-05-19 12:00 |
04:15:32.92 |
+18:25:32.7 |
HIP 19847 |
12.53 |
| 2026-05-20 00:00 |
04:16:01.43 |
+18:26:36.4 |
HIP 19847 |
15.10 |
| 2026-05-20 12:00 |
04:16:29.95 |
+18:27:39.7 |
HIP 19847 |
19.82 |
| 2026-05-21 00:00 |
04:16:58.50 |
+18:28:42.7 |
HIP 20056 |
20.06 |
| 2026-05-21 12:00 |
04:17:27.06 |
+18:29:45.3 |
HIP 20056 |
16.54 |
| 2026-05-22 00:00 |
04:17:55.64 |
+18:30:47.5 |
HIP 20056 |
15.45 |
| 2026-05-22 12:00 |
04:18:24.24 |
+18:31:49.4 |
HIP 20056 |
17.25 |
| 2026-05-23 00:00 |
04:18:52.85 |
+18:32:50.9 |
HIP 20056 |
21.23 |
| 2026-05-23 12:00 |
04:19:21.48 |
+18:33:52.1 |
HIP 20255 |
18.47 |
| 2026-05-24 00:00 |
04:19:50.12 |
+18:34:52.8 |
HIP 20255 |
12.73 |
| 2026-05-24 12:00 |
04:20:18.78 |
+18:35:53.2 |
HIP 20255 |
8.80 |
| 2026-05-25 00:00 |
04:20:47.46 |
+18:36:53.2 |
HIP 20255 |
9.33 |
| 2026-05-25 12:00 |
04:21:16.14 |
+18:37:52.9 |
HIP 20350 |
13.38 |
| 2026-05-26 00:00 |
04:21:44.84 |
+18:38:52.2 |
HIP 20350 |
14.13 |
| 2026-05-26 12:00 |
04:22:13.55 |
+18:39:51.0 |
HIP 20350 |
17.74 |
| 2026-05-27 00:00 |
04:22:42.28 |
+18:40:49.6 |
HIP 20350 |
22.90 |
| 2026-05-27 12:00 |
04:23:11.01 |
+18:41:47.7 |
HIP 20600 |
25.34 |
| 2026-05-28 00:00 |
04:23:39.75 |
+18:42:45.4 |
HIP 20600 |
19.19 |
| 2026-05-28 12:00 |
04:24:08.51 |
+18:43:42.8 |
HIP 20600 |
13.75 |
| 2026-05-29 00:00 |
04:24:37.27 |
+18:44:39.7 |
HIP 20600 |
10.21 |
| 2026-05-29 12:00 |
04:25:06.04 |
+18:45:36.3 |
HIP 20646 |
9.07 |
| 2026-05-30 00:00 |
04:25:34.82 |
+18:46:32.4 |
HIP 20686 |
6.64 |
| 2026-05-30 12:00 |
04:26:03.61 |
+18:47:28.2 |
HIP 20686 |
5.21 |
| 2026-05-31 00:00 |
04:26:32.40 |
+18:48:23.6 |
HIP 20686 |
10.24 |
| 2026-05-31 12:00 |
04:27:01.21 |
+18:49:18.6 |
HIP 20686 |
16.65 |
| 2026-06-01 00:00 |
04:27:30.01 |
+18:50:13.2 |
HIP 20769 |
18.24 |
| 2026-06-01 12:00 |
04:27:58.83 |
+18:51:07.3 |
HIP 20769 |
21.08 |
| 2026-06-02 00:00 |
04:28:27.64 |
+18:52:01.1 |
HIP 20889 |
18.94 |