| Parameter |
Value |
| Designation |
310P/Hill |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2015-04-19T01:39:38.698560Z |
| Orbit solution date (soln_date, UTC) |
2025-02-28T13:42:32Z |
| Obs used |
587 |
| NEO |
- |
| M1 |
13.500 |
| K1 |
11.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2017-01-08.0000000 |
| e |
0.42601974 |
| q (au) |
2.388747 |
| a (au) |
4.161724 |
| i (deg) |
13.186071 |
| Ω (om, deg) |
8.960664 |
| ω (w, deg) |
31.658059 |
| M (ma, deg) |
73.128566 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.263 + 3.893\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.263 |
| n |
3.893 |
| gf |
0.885 |
| gb |
-0.839 |
| k |
0.996 |
| δ90 |
1.000 |
| 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) |
| 2026-09-20 00:00 |
12:37:47.82 |
-04:59:33.3 |
HIP 61581 |
22.63 |
| 2026-09-20 12:00 |
12:38:09.28 |
-05:02:11.9 |
HIP 61687 |
19.48 |
| 2026-09-21 00:00 |
12:38:30.75 |
-05:04:50.5 |
HIP 61687 |
15.17 |
| 2026-09-21 12:00 |
12:38:52.24 |
-05:07:29.3 |
HIP 61687 |
12.32 |
| 2026-09-22 00:00 |
12:39:13.74 |
-05:10:08.1 |
HIP 61687 |
12.04 |
| 2026-09-22 12:00 |
12:39:35.26 |
-05:12:46.9 |
HIP 61687 |
14.47 |
| 2026-09-23 00:00 |
12:39:56.80 |
-05:15:25.8 |
HIP 61687 |
18.58 |
| 2026-09-23 12:00 |
12:40:18.35 |
-05:18:04.8 |
HIP 61687 |
23.52 |
| 2026-09-24 00:00 |
12:40:39.91 |
-05:20:43.8 |
HIP 61971 |
21.20 |
| 2026-09-24 12:00 |
12:41:01.49 |
-05:23:22.8 |
HIP 61971 |
17.66 |
| 2026-09-25 00:00 |
12:41:23.08 |
-05:26:01.9 |
HIP 61971 |
15.69 |
| 2026-09-25 12:00 |
12:41:44.68 |
-05:28:41.0 |
HIP 62013 |
12.76 |
| 2026-09-26 00:00 |
12:42:06.29 |
-05:31:20.2 |
HIP 62013 |
8.05 |
| 2026-09-26 12:00 |
12:42:27.92 |
-05:33:59.4 |
HIP 62013 |
6.23 |
| 2026-09-27 00:00 |
12:42:49.56 |
-05:36:38.6 |
HIP 62057 |
9.10 |
| 2026-09-27 12:00 |
12:43:11.20 |
-05:39:17.8 |
HIP 62057 |
5.13 |
| 2026-09-28 00:00 |
12:43:32.86 |
-05:41:57.1 |
HIP 62057 |
6.47 |
| 2026-09-28 12:00 |
12:43:54.53 |
-05:44:36.3 |
HIP 62057 |
11.38 |
| 2026-09-29 00:00 |
12:44:16.21 |
-05:47:15.6 |
HIP 62057 |
17.02 |
| 2026-09-29 12:00 |
12:44:37.89 |
-05:49:54.9 |
HIP 62190 |
20.50 |
| 2026-09-30 00:00 |
12:44:59.58 |
-05:52:34.2 |
HIP 62190 |
18.24 |
| 2026-09-30 12:00 |
12:45:21.28 |
-05:55:13.5 |
HIP 62190 |
17.82 |
| 2026-10-01 00:00 |
12:45:42.99 |
-05:57:52.9 |
HIP 62190 |
19.36 |
| 2026-10-01 12:00 |
12:46:04.71 |
-06:00:32.2 |
HIP 62190 |
22.45 |
| 2026-10-02 00:00 |
12:46:26.43 |
-06:03:11.5 |
HIP 62419 |
18.99 |
| 2026-10-02 12:00 |
12:46:48.15 |
-06:05:50.8 |
HIP 62419 |
16.51 |
| 2026-10-03 00:00 |
12:47:09.89 |
-06:08:30.1 |
HIP 62421 |
11.24 |
| 2026-10-03 12:00 |
12:47:31.62 |
-06:11:09.4 |
HIP 62421 |
6.96 |
| 2026-10-04 00:00 |
12:47:53.36 |
-06:13:48.7 |
HIP 62421 |
6.55 |
| 2026-10-04 12:00 |
12:48:15.10 |
-06:16:27.9 |
HIP 62421 |
10.49 |
| 2026-10-05 00:00 |
12:48:36.85 |
-06:19:07.1 |
HIP 62421 |
15.79 |
| 2026-10-05 12:00 |
12:48:58.60 |
-06:21:46.3 |
HIP 62421 |
21.48 |
| 2026-10-06 00:00 |
12:49:20.35 |
-06:24:25.5 |
HIP 62421 |
27.31 |
| 2026-10-06 12:00 |
12:49:42.10 |
-06:27:04.6 |
HIP 62605 |
25.73 |
| 2026-10-07 00:00 |
12:50:03.85 |
-06:29:43.7 |
HIP 62605 |
23.67 |
| 2026-10-07 12:00 |
12:50:25.60 |
-06:32:22.8 |
HIP 62605 |
23.04 |
| 2026-10-08 00:00 |
12:50:47.35 |
-06:35:01.8 |
HIP 62727 |
22.69 |
| 2026-10-08 12:00 |
12:51:09.09 |
-06:37:40.7 |
HIP 62727 |
19.07 |
| 2026-10-09 00:00 |
12:51:30.84 |
-06:40:19.6 |
HIP 62727 |
16.87 |
| 2026-10-09 12:00 |
12:51:52.58 |
-06:42:58.4 |
HIP 62727 |
16.67 |
| 2026-10-10 00:00 |
12:52:14.32 |
-06:45:37.2 |
HIP 62727 |
18.54 |
| 2026-10-10 12:00 |
12:52:36.05 |
-06:48:15.9 |
HIP 62851 |
20.02 |
| 2026-10-11 00:00 |
12:52:57.78 |
-06:50:54.5 |
HIP 62851 |
16.64 |