| 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) |
| 2026-05-12 00:00 |
16:05:57.15 |
-50:33:55.2 |
HIP 78805 |
17.91 |
| 2026-05-12 12:00 |
16:05:53.96 |
-50:33:54.8 |
HIP 78805 |
17.75 |
| 2026-05-13 00:00 |
16:05:50.77 |
-50:33:54.3 |
HIP 78805 |
17.60 |
| 2026-05-13 12:00 |
16:05:47.57 |
-50:33:53.6 |
HIP 78805 |
17.46 |
| 2026-05-14 00:00 |
16:05:44.36 |
-50:33:52.7 |
HIP 78805 |
17.35 |
| 2026-05-14 12:00 |
16:05:41.15 |
-50:33:51.7 |
HIP 78805 |
17.24 |
| 2026-05-15 00:00 |
16:05:37.94 |
-50:33:50.6 |
HIP 78805 |
17.16 |
| 2026-05-15 12:00 |
16:05:34.72 |
-50:33:49.3 |
HIP 78805 |
17.09 |
| 2026-05-16 00:00 |
16:05:31.49 |
-50:33:47.9 |
HIP 78805 |
17.04 |
| 2026-05-16 12:00 |
16:05:28.26 |
-50:33:46.3 |
HIP 78805 |
17.01 |
| 2026-05-17 00:00 |
16:05:25.03 |
-50:33:44.6 |
HIP 78805 |
16.99 |
| 2026-05-17 12:00 |
16:05:21.79 |
-50:33:42.7 |
HIP 78805 |
16.99 |
| 2026-05-18 00:00 |
16:05:18.55 |
-50:33:40.7 |
HIP 78805 |
17.01 |
| 2026-05-18 12:00 |
16:05:15.30 |
-50:33:38.5 |
HIP 78805 |
17.05 |
| 2026-05-19 00:00 |
16:05:12.06 |
-50:33:36.2 |
HIP 78805 |
17.11 |
| 2026-05-19 12:00 |
16:05:08.81 |
-50:33:33.8 |
HIP 78805 |
17.18 |
| 2026-05-20 00:00 |
16:05:05.56 |
-50:33:31.2 |
HIP 78805 |
17.27 |
| 2026-05-20 12:00 |
16:05:02.30 |
-50:33:28.4 |
HIP 78805 |
17.38 |
| 2026-05-21 00:00 |
16:04:59.05 |
-50:33:25.5 |
HIP 78805 |
17.51 |
| 2026-05-21 12:00 |
16:04:55.79 |
-50:33:22.5 |
HIP 78805 |
17.65 |
| 2026-05-22 00:00 |
16:04:52.53 |
-50:33:19.3 |
HIP 78805 |
17.81 |
| 2026-05-22 12:00 |
16:04:49.27 |
-50:33:16.0 |
HIP 78805 |
17.98 |
| 2026-05-23 00:00 |
16:04:46.01 |
-50:33:12.6 |
HIP 78805 |
18.17 |
| 2026-05-23 12:00 |
16:04:42.75 |
-50:33:09.0 |
HIP 78805 |
18.38 |
| 2026-05-24 00:00 |
16:04:39.49 |
-50:33:05.2 |
HIP 78805 |
18.60 |
| 2026-05-24 12:00 |
16:04:36.23 |
-50:33:01.3 |
HIP 78694 |
18.70 |
| 2026-05-25 00:00 |
16:04:32.97 |
-50:32:57.3 |
HIP 78694 |
18.57 |
| 2026-05-25 12:00 |
16:04:29.71 |
-50:32:53.2 |
HIP 78694 |
18.47 |
| 2026-05-26 00:00 |
16:04:26.45 |
-50:32:48.9 |
HIP 78694 |
18.38 |
| 2026-05-26 12:00 |
16:04:23.19 |
-50:32:44.4 |
HIP 78694 |
18.31 |
| 2026-05-27 00:00 |
16:04:19.94 |
-50:32:39.8 |
HIP 78694 |
18.25 |
| 2026-05-27 12:00 |
16:04:16.68 |
-50:32:35.1 |
HIP 78694 |
18.22 |
| 2026-05-28 00:00 |
16:04:13.43 |
-50:32:30.3 |
HIP 78694 |
18.20 |
| 2026-05-28 12:00 |
16:04:10.17 |
-50:32:25.3 |
HIP 78694 |
18.19 |
| 2026-05-29 00:00 |
16:04:06.93 |
-50:32:20.2 |
HIP 78694 |
18.21 |
| 2026-05-29 12:00 |
16:04:03.68 |
-50:32:14.9 |
HIP 78694 |
18.24 |
| 2026-05-30 00:00 |
16:04:00.43 |
-50:32:09.5 |
HIP 78694 |
18.28 |
| 2026-05-30 12:00 |
16:03:57.19 |
-50:32:04.0 |
HIP 78694 |
18.35 |
| 2026-05-31 00:00 |
16:03:53.95 |
-50:31:58.3 |
HIP 78694 |
18.43 |
| 2026-05-31 12:00 |
16:03:50.72 |
-50:31:52.5 |
HIP 78694 |
18.53 |
| 2026-06-01 00:00 |
16:03:47.49 |
-50:31:46.6 |
HIP 78694 |
18.64 |
| 2026-06-01 12:00 |
16:03:44.26 |
-50:31:40.5 |
HIP 78694 |
18.77 |
| 2026-06-02 00:00 |
16:03:41.04 |
-50:31:34.3 |
HIP 78578 |
18.67 |