| Parameter |
Value |
| Designation |
C/1991 B1 (Shoemaker-Levy) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1991-12-31T04:34:48.403200Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:40Z |
| Obs used |
429 |
| NEO |
- |
| M1 |
6.500 |
| K1 |
9.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1992-05-14.0000000 |
| e |
0.99357570 |
| q (au) |
2.265069 |
| a (au) |
352.578443 |
| i (deg) |
77.287941 |
| Ω (om, deg) |
145.130159 |
| ω (w, deg) |
74.368785 |
| M (ma, deg) |
0.020070 |
Magnitude
Scatter + Global Linear
$$
M_a = (3.371 + 5.121\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
3.371 |
| n |
5.121 |
| gf |
0.999 |
| gb |
-0.836 |
| k |
1.000 |
| δ90 |
9.998 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 1991-01-13 |
1991-04-17 |
+6.2454 |
-3.858 |
| 1991-04-17 |
1991-12-31 |
-2.7201 |
+1.245 |
| 1992-01-01 |
1992-06-26 |
+4.1272 |
-1.528 |
| 1992-06-26 |
1993-10-08 |
-3.5694 |
+1.839 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
00:49:27.34 |
-52:14:36.5 |
HIP 3656 |
28.09 |
| 2026-07-29 12:00 |
00:49:26.23 |
-52:15:03.9 |
HIP 3656 |
28.18 |
| 2026-07-30 00:00 |
00:49:25.09 |
-52:15:31.3 |
HIP 3656 |
28.26 |
| 2026-07-30 12:00 |
00:49:23.93 |
-52:15:58.7 |
HIP 3656 |
28.36 |
| 2026-07-31 00:00 |
00:49:22.75 |
-52:16:26.0 |
HIP 3656 |
28.45 |
| 2026-07-31 12:00 |
00:49:21.54 |
-52:16:53.3 |
HIP 3656 |
28.55 |
| 2026-08-01 00:00 |
00:49:20.31 |
-52:17:20.6 |
HIP 3656 |
28.66 |
| 2026-08-01 12:00 |
00:49:19.05 |
-52:17:47.8 |
HIP 3656 |
28.77 |
| 2026-08-02 00:00 |
00:49:17.77 |
-52:18:15.0 |
HIP 3656 |
28.89 |
| 2026-08-02 12:00 |
00:49:16.46 |
-52:18:42.1 |
HIP 3656 |
29.01 |
| 2026-08-03 00:00 |
00:49:15.13 |
-52:19:09.2 |
HIP 3656 |
29.13 |
| 2026-08-03 12:00 |
00:49:13.77 |
-52:19:36.2 |
HIP 3656 |
29.26 |
| 2026-08-04 00:00 |
00:49:12.40 |
-52:20:03.2 |
HIP 3656 |
29.39 |
| 2026-08-04 12:00 |
00:49:10.99 |
-52:20:30.1 |
HIP 3656 |
29.53 |
| 2026-08-05 00:00 |
00:49:09.56 |
-52:20:57.0 |
HIP 3656 |
29.68 |
| 2026-08-05 12:00 |
00:49:08.11 |
-52:21:23.8 |
HIP 3656 |
29.82 |
| 2026-08-06 00:00 |
00:49:06.64 |
-52:21:50.6 |
HIP 3656 |
29.97 |
| 2026-08-06 12:00 |
00:49:05.14 |
-52:22:17.2 |
HIP 3656 |
30.13 |
| 2026-08-07 00:00 |
00:49:03.62 |
-52:22:43.9 |
HIP 3656 |
30.29 |
| 2026-08-07 12:00 |
00:49:02.07 |
-52:23:10.4 |
HIP 3656 |
30.45 |
| 2026-08-08 00:00 |
00:49:00.50 |
-52:23:36.9 |
HIP 3656 |
30.62 |
| 2026-08-08 12:00 |
00:48:58.91 |
-52:24:03.3 |
HIP 3656 |
30.79 |
| 2026-08-09 00:00 |
00:48:57.29 |
-52:24:29.6 |
HIP 3656 |
30.97 |
| 2026-08-09 12:00 |
00:48:55.65 |
-52:24:55.9 |
HIP 3656 |
31.15 |
| 2026-08-10 00:00 |
00:48:53.99 |
-52:25:22.1 |
HIP 3656 |
31.34 |
| 2026-08-10 12:00 |
00:48:52.30 |
-52:25:48.2 |
HIP 3656 |
31.52 |
| 2026-08-11 00:00 |
00:48:50.59 |
-52:26:14.2 |
HIP 3656 |
31.72 |
| 2026-08-11 12:00 |
00:48:48.86 |
-52:26:40.2 |
HIP 3656 |
31.91 |
| 2026-08-12 00:00 |
00:48:47.10 |
-52:27:06.0 |
HIP 3656 |
32.11 |
| 2026-08-12 12:00 |
00:48:45.33 |
-52:27:31.8 |
HIP 3656 |
32.31 |
| 2026-08-13 00:00 |
00:48:43.53 |
-52:27:57.5 |
HIP 3656 |
32.52 |
| 2026-08-13 12:00 |
00:48:41.71 |
-52:28:23.1 |
HIP 3656 |
32.73 |
| 2026-08-14 00:00 |
00:48:39.86 |
-52:28:48.6 |
HIP 3656 |
32.95 |
| 2026-08-14 12:00 |
00:48:38.00 |
-52:29:13.9 |
HIP 3656 |
33.16 |
| 2026-08-15 00:00 |
00:48:36.11 |
-52:29:39.2 |
HIP 3656 |
33.38 |
| 2026-08-15 12:00 |
00:48:34.20 |
-52:30:04.4 |
HIP 3656 |
33.61 |
| 2026-08-16 00:00 |
00:48:32.27 |
-52:30:29.5 |
HIP 3656 |
33.84 |
| 2026-08-16 12:00 |
00:48:30.32 |
-52:30:54.5 |
HIP 3656 |
34.07 |
| 2026-08-17 00:00 |
00:48:28.34 |
-52:31:19.4 |
HIP 3656 |
34.30 |
| 2026-08-17 12:00 |
00:48:26.35 |
-52:31:44.2 |
HIP 3656 |
34.54 |
| 2026-08-18 00:00 |
00:48:24.33 |
-52:32:08.9 |
HIP 3656 |
34.78 |
| 2026-08-18 12:00 |
00:48:22.30 |
-52:32:33.4 |
HIP 3656 |
35.02 |
| 2026-08-19 00:00 |
00:48:20.24 |
-52:32:57.9 |
HIP 3656 |
35.27 |