| Parameter |
Value |
| Designation |
C/1986 E1 (Shoemaker) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1986-03-11T06:37:30.054720Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:33Z |
| Obs used |
37 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1986-06-17.0000000 |
| e |
0.94684032 |
| q (au) |
3.593858 |
| a (au) |
67.604972 |
| i (deg) |
159.808447 |
| Ω (om, deg) |
294.843600 |
| ω (w, deg) |
123.567998 |
| M (ma, deg) |
0.173276 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.195 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.195 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.502 |
| 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) |
| 2026-09-20 00:00 |
01:19:31.65 |
-13:21:43.0 |
HIP 6135 |
12.09 |
| 2026-09-20 12:00 |
01:19:29.67 |
-13:21:58.5 |
HIP 6135 |
11.58 |
| 2026-09-21 00:00 |
01:19:27.68 |
-13:22:14.0 |
HIP 6135 |
11.06 |
| 2026-09-21 12:00 |
01:19:25.69 |
-13:22:29.5 |
HIP 6135 |
10.54 |
| 2026-09-22 00:00 |
01:19:23.69 |
-13:22:44.8 |
HIP 6135 |
10.03 |
| 2026-09-22 12:00 |
01:19:21.68 |
-13:23:00.2 |
HIP 6135 |
9.52 |
| 2026-09-23 00:00 |
01:19:19.67 |
-13:23:15.4 |
HIP 6135 |
9.01 |
| 2026-09-23 12:00 |
01:19:17.65 |
-13:23:30.6 |
HIP 6135 |
8.51 |
| 2026-09-24 00:00 |
01:19:15.62 |
-13:23:45.8 |
HIP 6135 |
8.01 |
| 2026-09-24 12:00 |
01:19:13.59 |
-13:24:00.9 |
HIP 6135 |
7.52 |
| 2026-09-25 00:00 |
01:19:11.55 |
-13:24:15.9 |
HIP 6135 |
7.04 |
| 2026-09-25 12:00 |
01:19:09.50 |
-13:24:30.8 |
HIP 6135 |
6.56 |
| 2026-09-26 00:00 |
01:19:07.45 |
-13:24:45.7 |
HIP 6135 |
6.10 |
| 2026-09-26 12:00 |
01:19:05.39 |
-13:25:00.6 |
HIP 6135 |
5.65 |
| 2026-09-27 00:00 |
01:19:03.33 |
-13:25:15.3 |
HIP 6135 |
5.23 |
| 2026-09-27 12:00 |
01:19:01.26 |
-13:25:30.0 |
HIP 6135 |
4.83 |
| 2026-09-28 00:00 |
01:18:59.19 |
-13:25:44.6 |
HIP 6135 |
4.46 |
| 2026-09-28 12:00 |
01:18:57.11 |
-13:25:59.2 |
HIP 6135 |
4.13 |
| 2026-09-29 00:00 |
01:18:55.03 |
-13:26:13.6 |
HIP 6135 |
3.85 |
| 2026-09-29 12:00 |
01:18:52.94 |
-13:26:28.0 |
HIP 6135 |
3.64 |
| 2026-09-30 00:00 |
01:18:50.85 |
-13:26:42.4 |
HIP 6135 |
3.51 |
| 2026-09-30 12:00 |
01:18:48.75 |
-13:26:56.6 |
HIP 6135 |
3.46 |
| 2026-10-01 00:00 |
01:18:46.64 |
-13:27:10.8 |
HIP 6135 |
3.50 |
| 2026-10-01 12:00 |
01:18:44.54 |
-13:27:24.9 |
HIP 6135 |
3.63 |
| 2026-10-02 00:00 |
01:18:42.43 |
-13:27:38.9 |
HIP 6135 |
3.84 |
| 2026-10-02 12:00 |
01:18:40.31 |
-13:27:52.8 |
HIP 6135 |
4.11 |
| 2026-10-03 00:00 |
01:18:38.19 |
-13:28:06.7 |
HIP 6135 |
4.44 |
| 2026-10-03 12:00 |
01:18:36.07 |
-13:28:20.5 |
HIP 6135 |
4.81 |
| 2026-10-04 00:00 |
01:18:33.94 |
-13:28:34.2 |
HIP 6135 |
5.21 |
| 2026-10-04 12:00 |
01:18:31.82 |
-13:28:47.8 |
HIP 6135 |
5.64 |
| 2026-10-05 00:00 |
01:18:29.68 |
-13:29:01.3 |
HIP 6135 |
6.09 |
| 2026-10-05 12:00 |
01:18:27.55 |
-13:29:14.7 |
HIP 6135 |
6.56 |
| 2026-10-06 00:00 |
01:18:25.41 |
-13:29:28.1 |
HIP 6135 |
7.04 |
| 2026-10-06 12:00 |
01:18:23.27 |
-13:29:41.4 |
HIP 6135 |
7.54 |
| 2026-10-07 00:00 |
01:18:21.12 |
-13:29:54.5 |
HIP 6135 |
8.04 |
| 2026-10-07 12:00 |
01:18:18.97 |
-13:30:07.6 |
HIP 6135 |
8.55 |
| 2026-10-08 00:00 |
01:18:16.83 |
-13:30:20.6 |
HIP 6135 |
9.06 |
| 2026-10-08 12:00 |
01:18:14.67 |
-13:30:33.5 |
HIP 6135 |
9.58 |
| 2026-10-09 00:00 |
01:18:12.52 |
-13:30:46.3 |
HIP 6135 |
10.11 |
| 2026-10-09 12:00 |
01:18:10.37 |
-13:30:59.0 |
HIP 6135 |
10.64 |
| 2026-10-10 00:00 |
01:18:08.21 |
-13:31:11.6 |
HIP 6135 |
11.17 |
| 2026-10-10 12:00 |
01:18:06.05 |
-13:31:24.1 |
HIP 6135 |
11.70 |
| 2026-10-11 00:00 |
01:18:03.89 |
-13:31:36.5 |
HIP 6135 |
12.24 |