155P/Shoemaker 3
| Parameter |
Value |
| Designation |
155P/Shoemaker 3 |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2002-12-08T02:13:30.930240Z |
| Orbit solution date (soln_date, UTC) |
2022-12-31T16:13:39Z |
| Obs used |
1966 |
| NEO |
- |
| M1 |
10.000 |
| K1 |
12.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2011-05-21.0000000 |
| e |
0.72610716 |
| q (au) |
1.806142 |
| a (au) |
6.594337 |
| i (deg) |
6.398094 |
| Ω (om, deg) |
97.276219 |
| ω (w, deg) |
14.601886 |
| M (ma, deg) |
179.609901 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.890 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.890 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| 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) |
| 2026-02-03 00:00 |
18:57:15.30 |
-23:08:03.5 |
HIP 92980 |
9.51 |
| 2026-02-03 12:00 |
18:57:26.68 |
-23:07:51.2 |
HIP 92980 |
12.14 |
| 2026-02-04 00:00 |
18:57:38.02 |
-23:07:39.0 |
HIP 92980 |
14.75 |
| 2026-02-04 12:00 |
18:57:49.32 |
-23:07:26.7 |
HIP 92980 |
17.36 |
| 2026-02-05 00:00 |
18:58:00.57 |
-23:07:14.5 |
HIP 92980 |
19.95 |
| 2026-02-05 12:00 |
18:58:11.78 |
-23:07:02.3 |
HIP 93239 |
19.97 |
| 2026-02-06 00:00 |
18:58:22.94 |
-23:06:50.1 |
HIP 93239 |
17.82 |
| 2026-02-06 12:00 |
18:58:34.06 |
-23:06:38.0 |
HIP 93239 |
15.80 |
| 2026-02-07 00:00 |
18:58:45.13 |
-23:06:25.8 |
HIP 93239 |
13.96 |
| 2026-02-07 12:00 |
18:58:56.15 |
-23:06:13.7 |
HIP 93239 |
12.39 |
| 2026-02-08 00:00 |
18:59:07.13 |
-23:06:01.6 |
HIP 93239 |
11.19 |
| 2026-02-08 12:00 |
18:59:18.05 |
-23:05:49.6 |
HIP 93239 |
10.47 |
| 2026-02-09 00:00 |
18:59:28.93 |
-23:05:37.6 |
HIP 93288 |
8.31 |
| 2026-02-09 12:00 |
18:59:39.76 |
-23:05:25.6 |
HIP 93288 |
5.85 |
| 2026-02-10 00:00 |
18:59:50.53 |
-23:05:13.6 |
HIP 93288 |
3.46 |
| 2026-02-10 12:00 |
19:00:01.26 |
-23:05:01.7 |
HIP 93288 |
1.42 |
| 2026-02-11 00:00 |
19:00:11.93 |
-23:04:49.8 |
HIP 93288 |
2.07 |
| 2026-02-11 12:00 |
19:00:22.56 |
-23:04:38.0 |
HIP 93288 |
4.31 |
| 2026-02-12 00:00 |
19:00:33.13 |
-23:04:26.2 |
HIP 93288 |
6.69 |
| 2026-02-12 12:00 |
19:00:43.65 |
-23:04:14.4 |
HIP 93288 |
9.09 |
| 2026-02-13 00:00 |
19:00:54.11 |
-23:04:02.7 |
HIP 93288 |
11.49 |
| 2026-02-13 12:00 |
19:01:04.52 |
-23:03:51.0 |
HIP 93405 |
10.81 |
| 2026-02-14 00:00 |
19:01:14.87 |
-23:03:39.4 |
HIP 93405 |
10.25 |
| 2026-02-14 12:00 |
19:01:25.17 |
-23:03:27.8 |
HIP 93405 |
10.23 |
| 2026-02-15 00:00 |
19:01:35.41 |
-23:03:16.3 |
HIP 93405 |
10.75 |
| 2026-02-15 12:00 |
19:01:45.60 |
-23:03:04.8 |
HIP 93405 |
11.72 |
| 2026-02-16 00:00 |
19:01:55.73 |
-23:02:53.4 |
HIP 93405 |
13.04 |
| 2026-02-16 12:00 |
19:02:05.80 |
-23:02:42.0 |
HIP 93405 |
14.61 |
| 2026-02-17 00:00 |
19:02:15.81 |
-23:02:30.7 |
HIP 93405 |
16.35 |
| 2026-02-17 12:00 |
19:02:25.76 |
-23:02:19.4 |
HIP 93405 |
18.20 |
| 2026-02-18 00:00 |
19:02:35.65 |
-23:02:08.2 |
HIP 93405 |
20.13 |
| 2026-02-18 12:00 |
19:02:45.49 |
-23:01:57.1 |
HIP 93649 |
21.99 |
| 2026-02-19 00:00 |
19:02:55.26 |
-23:01:46.0 |
HIP 93649 |
19.84 |
| 2026-02-19 12:00 |
19:03:04.97 |
-23:01:35.0 |
HIP 93649 |
17.74 |
| 2026-02-20 00:00 |
19:03:14.61 |
-23:01:24.0 |
HIP 93649 |
15.69 |
| 2026-02-20 12:00 |
19:03:24.20 |
-23:01:13.1 |
HIP 93649 |
13.70 |
| 2026-02-21 00:00 |
19:03:33.72 |
-23:01:02.3 |
HIP 93649 |
11.81 |
| 2026-02-21 12:00 |
19:03:43.18 |
-23:00:51.6 |
HIP 93649 |
10.05 |
| 2026-02-22 00:00 |
19:03:52.57 |
-23:00:40.9 |
HIP 93649 |
8.50 |
| 2026-02-22 12:00 |
19:04:01.90 |
-23:00:30.3 |
HIP 93649 |
7.29 |
| 2026-02-23 00:00 |
19:04:11.16 |
-23:00:19.8 |
HIP 93649 |
6.58 |
| 2026-02-23 12:00 |
19:04:20.36 |
-23:00:09.3 |
HIP 93649 |
6.52 |
| 2026-02-24 00:00 |
19:04:29.49 |
-22:59:59.0 |
HIP 93649 |
7.12 |