| 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
$$
M_a = (6.197 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.197 |
| n |
6.000 |
| gf |
0.961 |
| gb |
-0.509 |
| k |
1.000 |
| δ90 |
9.900 |
| 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 |
01:20:14.92 |
-12:37:20.0 |
HIP 6305 |
13.27 |
| 2026-05-12 12:00 |
01:20:16.56 |
-12:37:16.4 |
HIP 6305 |
12.97 |
| 2026-05-13 00:00 |
01:20:18.19 |
-12:37:12.9 |
HIP 6305 |
12.68 |
| 2026-05-13 12:00 |
01:20:19.81 |
-12:37:09.5 |
HIP 6305 |
12.39 |
| 2026-05-14 00:00 |
01:20:21.43 |
-12:37:06.3 |
HIP 6305 |
12.11 |
| 2026-05-14 12:00 |
01:20:23.03 |
-12:37:03.2 |
HIP 6305 |
11.84 |
| 2026-05-15 00:00 |
01:20:24.63 |
-12:37:00.2 |
HIP 6305 |
11.57 |
| 2026-05-15 12:00 |
01:20:26.22 |
-12:36:57.3 |
HIP 6305 |
11.31 |
| 2026-05-16 00:00 |
01:20:27.80 |
-12:36:54.6 |
HIP 6305 |
11.06 |
| 2026-05-16 12:00 |
01:20:29.37 |
-12:36:52.0 |
HIP 6305 |
10.82 |
| 2026-05-17 00:00 |
01:20:30.94 |
-12:36:49.6 |
HIP 6305 |
10.59 |
| 2026-05-17 12:00 |
01:20:32.49 |
-12:36:47.3 |
HIP 6305 |
10.36 |
| 2026-05-18 00:00 |
01:20:34.03 |
-12:36:45.1 |
HIP 6305 |
10.14 |
| 2026-05-18 12:00 |
01:20:35.57 |
-12:36:43.0 |
HIP 6305 |
9.94 |
| 2026-05-19 00:00 |
01:20:37.09 |
-12:36:41.1 |
HIP 6305 |
9.74 |
| 2026-05-19 12:00 |
01:20:38.61 |
-12:36:39.3 |
HIP 6305 |
9.55 |
| 2026-05-20 00:00 |
01:20:40.11 |
-12:36:37.6 |
HIP 6305 |
9.38 |
| 2026-05-20 12:00 |
01:20:41.61 |
-12:36:36.1 |
HIP 6305 |
9.21 |
| 2026-05-21 00:00 |
01:20:43.09 |
-12:36:34.7 |
HIP 6305 |
9.06 |
| 2026-05-21 12:00 |
01:20:44.57 |
-12:36:33.4 |
HIP 6305 |
8.91 |
| 2026-05-22 00:00 |
01:20:46.03 |
-12:36:32.3 |
HIP 6305 |
8.78 |
| 2026-05-22 12:00 |
01:20:47.49 |
-12:36:31.3 |
HIP 6305 |
8.66 |
| 2026-05-23 00:00 |
01:20:48.93 |
-12:36:30.4 |
HIP 6305 |
8.55 |
| 2026-05-23 12:00 |
01:20:50.37 |
-12:36:29.7 |
HIP 6305 |
8.45 |
| 2026-05-24 00:00 |
01:20:51.79 |
-12:36:29.1 |
HIP 6305 |
8.37 |
| 2026-05-24 12:00 |
01:20:53.20 |
-12:36:28.6 |
HIP 6305 |
8.29 |
| 2026-05-25 00:00 |
01:20:54.60 |
-12:36:28.2 |
HIP 6305 |
8.23 |
| 2026-05-25 12:00 |
01:20:55.99 |
-12:36:28.0 |
HIP 6305 |
8.18 |
| 2026-05-26 00:00 |
01:20:57.37 |
-12:36:28.0 |
HIP 6305 |
8.15 |
| 2026-05-26 12:00 |
01:20:58.74 |
-12:36:28.0 |
HIP 6305 |
8.12 |
| 2026-05-27 00:00 |
01:21:00.09 |
-12:36:28.2 |
HIP 6305 |
8.11 |
| 2026-05-27 12:00 |
01:21:01.44 |
-12:36:28.5 |
HIP 6305 |
8.10 |
| 2026-05-28 00:00 |
01:21:02.77 |
-12:36:29.0 |
HIP 6305 |
8.11 |
| 2026-05-28 12:00 |
01:21:04.09 |
-12:36:29.6 |
HIP 6305 |
8.13 |
| 2026-05-29 00:00 |
01:21:05.40 |
-12:36:30.3 |
HIP 6305 |
8.16 |
| 2026-05-29 12:00 |
01:21:06.70 |
-12:36:31.1 |
HIP 6305 |
8.20 |
| 2026-05-30 00:00 |
01:21:07.99 |
-12:36:32.1 |
HIP 6305 |
8.25 |
| 2026-05-30 12:00 |
01:21:09.27 |
-12:36:33.2 |
HIP 6305 |
8.30 |
| 2026-05-31 00:00 |
01:21:10.53 |
-12:36:34.5 |
HIP 6305 |
8.37 |
| 2026-05-31 12:00 |
01:21:11.78 |
-12:36:35.8 |
HIP 6305 |
8.44 |
| 2026-06-01 00:00 |
01:21:13.02 |
-12:36:37.3 |
HIP 6305 |
8.52 |
| 2026-06-01 12:00 |
01:21:14.25 |
-12:36:39.0 |
HIP 6305 |
8.61 |
| 2026-06-02 00:00 |
01:21:15.46 |
-12:36:40.7 |
HIP 6305 |
8.70 |