| Parameter |
Value |
| Designation |
232P/Hill |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2009-10-01T10:51:18.581760Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:28:01Z |
| Obs used |
297 |
| NEO |
- |
| M1 |
7.200 |
| K1 |
19.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2010-10-02.0000000 |
| e |
0.33492236 |
| q (au) |
2.982861 |
| a (au) |
4.484981 |
| i (deg) |
14.635076 |
| Ω (om, deg) |
56.129136 |
| ω (w, deg) |
53.417372 |
| M (ma, deg) |
37.932128 |
Magnitude
Scatter + Global Linear
$$
M_a = (9.156 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.156 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.998 |
| 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) |
| 2026-05-12 00:00 |
23:58:46.69 |
-14:02:45.8 |
HIP 118205 |
5.60 |
| 2026-05-12 12:00 |
23:59:07.83 |
-14:01:15.7 |
HIP 118205 |
10.23 |
| 2026-05-13 00:00 |
23:59:28.88 |
-13:59:46.5 |
HIP 118205 |
15.31 |
| 2026-05-13 12:00 |
23:59:49.86 |
-13:58:18.2 |
HIP 118205 |
20.48 |
| 2026-05-14 00:00 |
00:00:10.75 |
-13:56:50.8 |
HIP 118205 |
25.68 |
| 2026-05-14 12:00 |
00:00:31.55 |
-13:55:24.3 |
HIP 118205 |
30.88 |
| 2026-05-15 00:00 |
00:00:52.27 |
-13:53:58.6 |
HIP 26 |
31.36 |
| 2026-05-15 12:00 |
00:01:12.90 |
-13:52:34.0 |
HIP 26 |
31.67 |
| 2026-05-16 00:00 |
00:01:33.45 |
-13:51:10.2 |
HIP 179 |
28.70 |
| 2026-05-16 12:00 |
00:01:53.91 |
-13:49:47.3 |
HIP 179 |
25.93 |
| 2026-05-17 00:00 |
00:02:14.28 |
-13:48:25.4 |
HIP 179 |
23.98 |
| 2026-05-17 12:00 |
00:02:34.56 |
-13:47:04.4 |
HIP 179 |
23.04 |
| 2026-05-18 00:00 |
00:02:54.75 |
-13:45:44.4 |
HIP 179 |
23.23 |
| 2026-05-18 12:00 |
00:03:14.85 |
-13:44:25.2 |
HIP 179 |
24.49 |
| 2026-05-19 00:00 |
00:03:34.86 |
-13:43:07.1 |
HIP 179 |
26.66 |
| 2026-05-19 12:00 |
00:03:54.78 |
-13:41:49.9 |
HIP 287 |
28.71 |
| 2026-05-20 00:00 |
00:04:14.60 |
-13:40:33.6 |
HIP 287 |
28.80 |
| 2026-05-20 12:00 |
00:04:34.33 |
-13:39:18.3 |
HIP 287 |
29.74 |
| 2026-05-21 00:00 |
00:04:53.96 |
-13:38:04.0 |
HIP 554 |
28.14 |
| 2026-05-21 12:00 |
00:05:13.50 |
-13:36:50.6 |
HIP 554 |
23.95 |
| 2026-05-22 00:00 |
00:05:32.94 |
-13:35:38.2 |
HIP 554 |
20.10 |
| 2026-05-22 12:00 |
00:05:52.28 |
-13:34:26.8 |
HIP 554 |
16.80 |
| 2026-05-23 00:00 |
00:06:11.53 |
-13:33:16.4 |
HIP 554 |
14.39 |
| 2026-05-23 12:00 |
00:06:30.67 |
-13:32:06.9 |
HIP 554 |
13.36 |
| 2026-05-24 00:00 |
00:06:49.72 |
-13:30:58.4 |
HIP 554 |
13.97 |
| 2026-05-24 12:00 |
00:07:08.67 |
-13:29:51.0 |
HIP 554 |
16.02 |
| 2026-05-25 00:00 |
00:07:27.52 |
-13:28:44.5 |
HIP 554 |
19.03 |
| 2026-05-25 12:00 |
00:07:46.27 |
-13:27:39.0 |
HIP 554 |
22.59 |
| 2026-05-26 00:00 |
00:08:04.91 |
-13:26:34.5 |
HIP 554 |
26.48 |
| 2026-05-26 12:00 |
00:08:23.45 |
-13:25:31.0 |
HIP 554 |
30.55 |
| 2026-05-27 00:00 |
00:08:41.89 |
-13:24:28.5 |
HIP 554 |
34.74 |
| 2026-05-27 12:00 |
00:09:00.23 |
-13:23:27.1 |
HIP 554 |
38.99 |
| 2026-05-28 00:00 |
00:09:18.46 |
-13:22:26.7 |
HIP 887 |
39.24 |
| 2026-05-28 12:00 |
00:09:36.58 |
-13:21:27.2 |
HIP 887 |
37.67 |
| 2026-05-29 00:00 |
00:09:54.60 |
-13:20:28.8 |
HIP 887 |
36.60 |
| 2026-05-29 12:00 |
00:10:12.51 |
-13:19:31.5 |
HIP 887 |
36.05 |
| 2026-05-30 00:00 |
00:10:30.32 |
-13:18:35.2 |
HIP 1012 |
35.63 |
| 2026-05-30 12:00 |
00:10:48.01 |
-13:17:39.9 |
HIP 1012 |
32.52 |
| 2026-05-31 00:00 |
00:11:05.60 |
-13:16:45.6 |
HIP 1012 |
29.75 |
| 2026-05-31 12:00 |
00:11:23.08 |
-13:15:52.4 |
HIP 1012 |
27.40 |
| 2026-06-01 00:00 |
00:11:40.44 |
-13:15:00.3 |
HIP 1012 |
25.58 |
| 2026-06-01 12:00 |
00:11:57.69 |
-13:14:09.2 |
HIP 1012 |
24.38 |
| 2026-06-02 00:00 |
00:12:14.83 |
-13:13:19.2 |
HIP 1012 |
23.89 |