| Parameter |
Value |
| Designation |
C/1992 U1 (Shoemaker) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1993-03-25T16:18:34.217280Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:44Z |
| Obs used |
212 |
| NEO |
- |
| M1 |
9.200 |
| K1 |
11.250 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1993-02-25.0000000 |
| e |
0.99944533 |
| q (au) |
2.313656 |
| a (au) |
4171.194372 |
| i (deg) |
65.985593 |
| Ω (om, deg) |
55.299020 |
| ω (w, deg) |
54.864153 |
| M (ma, deg) |
359.999895 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.951 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.951 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.664 |
| k |
0.800 |
| 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) |
| 2026-07-29 00:00 |
15:58:56.83 |
-50:08:57.1 |
HIP 78150 |
15.87 |
| 2026-07-29 12:00 |
15:58:55.48 |
-50:08:41.8 |
HIP 78150 |
15.79 |
| 2026-07-30 00:00 |
15:58:54.15 |
-50:08:26.6 |
HIP 78150 |
15.73 |
| 2026-07-30 12:00 |
15:58:52.85 |
-50:08:11.3 |
HIP 78150 |
15.68 |
| 2026-07-31 00:00 |
15:58:51.57 |
-50:07:56.0 |
HIP 78150 |
15.64 |
| 2026-07-31 12:00 |
15:58:50.32 |
-50:07:40.7 |
HIP 78150 |
15.60 |
| 2026-08-01 00:00 |
15:58:49.09 |
-50:07:25.4 |
HIP 78150 |
15.58 |
| 2026-08-01 12:00 |
15:58:47.89 |
-50:07:10.1 |
HIP 78150 |
15.57 |
| 2026-08-02 00:00 |
15:58:46.72 |
-50:06:54.8 |
HIP 78150 |
15.57 |
| 2026-08-02 12:00 |
15:58:45.56 |
-50:06:39.5 |
HIP 78150 |
15.57 |
| 2026-08-03 00:00 |
15:58:44.44 |
-50:06:24.2 |
HIP 78150 |
15.59 |
| 2026-08-03 12:00 |
15:58:43.34 |
-50:06:08.9 |
HIP 78150 |
15.62 |
| 2026-08-04 00:00 |
15:58:42.27 |
-50:05:53.5 |
HIP 78150 |
15.65 |
| 2026-08-04 12:00 |
15:58:41.22 |
-50:05:38.2 |
HIP 78150 |
15.70 |
| 2026-08-05 00:00 |
15:58:40.20 |
-50:05:22.9 |
HIP 78150 |
15.75 |
| 2026-08-05 12:00 |
15:58:39.20 |
-50:05:07.6 |
HIP 78150 |
15.81 |
| 2026-08-06 00:00 |
15:58:38.24 |
-50:04:52.3 |
HIP 78150 |
15.88 |
| 2026-08-06 12:00 |
15:58:37.29 |
-50:04:37.0 |
HIP 78150 |
15.96 |
| 2026-08-07 00:00 |
15:58:36.38 |
-50:04:21.7 |
HIP 78150 |
16.05 |
| 2026-08-07 12:00 |
15:58:35.48 |
-50:04:06.4 |
HIP 78150 |
16.14 |
| 2026-08-08 00:00 |
15:58:34.62 |
-50:03:51.2 |
HIP 78150 |
16.24 |
| 2026-08-08 12:00 |
15:58:33.78 |
-50:03:35.9 |
HIP 78150 |
16.35 |
| 2026-08-09 00:00 |
15:58:32.97 |
-50:03:20.6 |
HIP 78150 |
16.47 |
| 2026-08-09 12:00 |
15:58:32.19 |
-50:03:05.4 |
HIP 78150 |
16.59 |
| 2026-08-10 00:00 |
15:58:31.43 |
-50:02:50.2 |
HIP 78150 |
16.71 |
| 2026-08-10 12:00 |
15:58:30.70 |
-50:02:35.0 |
HIP 78150 |
16.85 |
| 2026-08-11 00:00 |
15:58:30.00 |
-50:02:19.8 |
HIP 78150 |
16.99 |
| 2026-08-11 12:00 |
15:58:29.32 |
-50:02:04.6 |
HIP 78150 |
17.13 |
| 2026-08-12 00:00 |
15:58:28.67 |
-50:01:49.4 |
HIP 78150 |
17.28 |
| 2026-08-12 12:00 |
15:58:28.04 |
-50:01:34.3 |
HIP 78150 |
17.44 |
| 2026-08-13 00:00 |
15:58:27.45 |
-50:01:19.2 |
HIP 78086 |
17.38 |
| 2026-08-13 12:00 |
15:58:26.88 |
-50:01:04.1 |
HIP 78086 |
17.33 |
| 2026-08-14 00:00 |
15:58:26.34 |
-50:00:49.0 |
HIP 78086 |
17.28 |
| 2026-08-14 12:00 |
15:58:25.82 |
-50:00:34.0 |
HIP 78086 |
17.24 |
| 2026-08-15 00:00 |
15:58:25.33 |
-50:00:19.0 |
HIP 78086 |
17.21 |
| 2026-08-15 12:00 |
15:58:24.87 |
-50:00:04.0 |
HIP 78086 |
17.19 |
| 2026-08-16 00:00 |
15:58:24.44 |
-49:59:49.1 |
HIP 78086 |
17.18 |
| 2026-08-16 12:00 |
15:58:24.03 |
-49:59:34.1 |
HIP 78086 |
17.17 |
| 2026-08-17 00:00 |
15:58:23.65 |
-49:59:19.3 |
HIP 78086 |
17.18 |
| 2026-08-17 12:00 |
15:58:23.30 |
-49:59:04.4 |
HIP 78086 |
17.19 |
| 2026-08-18 00:00 |
15:58:22.98 |
-49:58:49.6 |
HIP 78086 |
17.20 |
| 2026-08-18 12:00 |
15:58:22.68 |
-49:58:34.8 |
HIP 78086 |
17.23 |
| 2026-08-19 00:00 |
15:58:22.41 |
-49:58:20.1 |
HIP 78086 |
17.26 |