| Parameter |
Value |
| Designation |
178P/Hug-Bell |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2013-07-23T00:23:50.688960Z |
| Orbit solution date (soln_date, UTC) |
2024-08-25T21:12:14Z |
| Obs used |
1037 |
| NEO |
- |
| M1 |
13.200 |
| K1 |
11.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2012-11-23.0000000 |
| e |
0.47299053 |
| q (au) |
1.933838 |
| a (au) |
3.669456 |
| i (deg) |
10.975306 |
| Ω (om, deg) |
103.574883 |
| ω (w, deg) |
296.946648 |
| M (ma, deg) |
326.065091 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.018 + 4.996\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.018 |
| n |
4.996 |
| gf |
1.000 |
| gb |
-0.833 |
| k |
0.999 |
| 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 |
20:17:44.32 |
-20:26:43.5 |
HIP 100000 |
29.84 |
| 2026-05-12 12:00 |
20:17:53.92 |
-20:27:14.4 |
HIP 100000 |
30.92 |
| 2026-05-13 00:00 |
20:18:03.25 |
-20:27:46.5 |
HIP 100000 |
32.13 |
| 2026-05-13 12:00 |
20:18:12.33 |
-20:28:19.8 |
HIP 100000 |
33.43 |
| 2026-05-14 00:00 |
20:18:21.14 |
-20:28:54.3 |
HIP 100201 |
31.95 |
| 2026-05-14 12:00 |
20:18:29.69 |
-20:29:29.9 |
HIP 100201 |
30.51 |
| 2026-05-15 00:00 |
20:18:37.97 |
-20:30:06.8 |
HIP 100201 |
29.16 |
| 2026-05-15 12:00 |
20:18:45.98 |
-20:30:44.9 |
HIP 100201 |
27.90 |
| 2026-05-16 00:00 |
20:18:53.72 |
-20:31:24.2 |
HIP 100201 |
26.72 |
| 2026-05-16 12:00 |
20:19:01.20 |
-20:32:04.8 |
HIP 100201 |
25.62 |
| 2026-05-17 00:00 |
20:19:08.40 |
-20:32:46.6 |
HIP 100201 |
24.61 |
| 2026-05-17 12:00 |
20:19:15.33 |
-20:33:29.6 |
HIP 100201 |
23.68 |
| 2026-05-18 00:00 |
20:19:21.98 |
-20:34:13.9 |
HIP 100201 |
22.83 |
| 2026-05-18 12:00 |
20:19:28.35 |
-20:34:59.5 |
HIP 100201 |
22.06 |
| 2026-05-19 00:00 |
20:19:34.45 |
-20:35:46.4 |
HIP 100201 |
21.37 |
| 2026-05-19 12:00 |
20:19:40.27 |
-20:36:34.5 |
HIP 100201 |
20.75 |
| 2026-05-20 00:00 |
20:19:45.81 |
-20:37:23.9 |
HIP 100201 |
20.20 |
| 2026-05-20 12:00 |
20:19:51.07 |
-20:38:14.6 |
HIP 100201 |
19.71 |
| 2026-05-21 00:00 |
20:19:56.05 |
-20:39:06.6 |
HIP 100201 |
19.28 |
| 2026-05-21 12:00 |
20:20:00.74 |
-20:39:59.9 |
HIP 100201 |
18.90 |
| 2026-05-22 00:00 |
20:20:05.15 |
-20:40:54.5 |
HIP 100201 |
18.57 |
| 2026-05-22 12:00 |
20:20:09.27 |
-20:41:50.4 |
HIP 100201 |
18.29 |
| 2026-05-23 00:00 |
20:20:13.11 |
-20:42:47.6 |
HIP 100201 |
18.04 |
| 2026-05-23 12:00 |
20:20:16.66 |
-20:43:46.1 |
HIP 100201 |
17.82 |
| 2026-05-24 00:00 |
20:20:19.92 |
-20:44:46.0 |
HIP 100201 |
17.63 |
| 2026-05-24 12:00 |
20:20:22.89 |
-20:45:47.2 |
HIP 100201 |
17.46 |
| 2026-05-25 00:00 |
20:20:25.57 |
-20:46:49.7 |
HIP 100201 |
17.30 |
| 2026-05-25 12:00 |
20:20:27.96 |
-20:47:53.6 |
HIP 100201 |
17.16 |
| 2026-05-26 00:00 |
20:20:30.05 |
-20:48:58.8 |
HIP 100201 |
17.04 |
| 2026-05-26 12:00 |
20:20:31.85 |
-20:50:05.4 |
HIP 100201 |
16.92 |
| 2026-05-27 00:00 |
20:20:33.36 |
-20:51:13.3 |
HIP 100201 |
16.82 |
| 2026-05-27 12:00 |
20:20:34.57 |
-20:52:22.5 |
HIP 100201 |
16.73 |
| 2026-05-28 00:00 |
20:20:35.48 |
-20:53:33.1 |
HIP 100201 |
16.64 |
| 2026-05-28 12:00 |
20:20:36.09 |
-20:54:45.1 |
HIP 100201 |
16.57 |
| 2026-05-29 00:00 |
20:20:36.41 |
-20:55:58.4 |
HIP 100201 |
16.52 |
| 2026-05-29 12:00 |
20:20:36.42 |
-20:57:13.1 |
HIP 100201 |
16.49 |
| 2026-05-30 00:00 |
20:20:36.13 |
-20:58:29.2 |
HIP 100201 |
16.48 |
| 2026-05-30 12:00 |
20:20:35.54 |
-20:59:46.6 |
HIP 100201 |
16.51 |
| 2026-05-31 00:00 |
20:20:34.64 |
-21:01:05.4 |
HIP 100201 |
16.57 |
| 2026-05-31 12:00 |
20:20:33.44 |
-21:02:25.6 |
HIP 100201 |
16.68 |
| 2026-06-01 00:00 |
20:20:31.93 |
-21:03:47.1 |
HIP 100201 |
16.84 |
| 2026-06-01 12:00 |
20:20:30.11 |
-21:05:10.1 |
HIP 100201 |
17.07 |
| 2026-06-02 00:00 |
20:20:27.99 |
-21:06:34.4 |
HIP 100201 |
17.36 |