| 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) |
| 2026-07-29 00:00 |
12:03:35.65 |
-00:38:51.1 |
HIP 58800 |
12.94 |
| 2026-07-29 12:00 |
12:03:51.81 |
-00:41:00.6 |
HIP 58800 |
11.34 |
| 2026-07-30 00:00 |
12:04:08.05 |
-00:43:10.5 |
HIP 58800 |
11.49 |
| 2026-07-30 12:00 |
12:04:24.37 |
-00:45:20.9 |
HIP 58800 |
13.35 |
| 2026-07-31 00:00 |
12:04:40.77 |
-00:47:31.8 |
HIP 58800 |
16.36 |
| 2026-07-31 12:00 |
12:04:57.26 |
-00:49:43.1 |
HIP 58800 |
20.03 |
| 2026-08-01 00:00 |
12:05:13.82 |
-00:51:55.0 |
HIP 58904 |
18.98 |
| 2026-08-01 12:00 |
12:05:30.47 |
-00:54:07.2 |
HIP 58904 |
19.00 |
| 2026-08-02 00:00 |
12:05:47.19 |
-00:56:20.0 |
HIP 58904 |
20.17 |
| 2026-08-02 12:00 |
12:06:04.00 |
-00:58:33.2 |
HIP 58904 |
22.32 |
| 2026-08-03 00:00 |
12:06:20.88 |
-01:00:46.8 |
HIP 58904 |
25.20 |
| 2026-08-03 12:00 |
12:06:37.84 |
-01:03:00.9 |
HIP 59102 |
26.58 |
| 2026-08-04 00:00 |
12:06:54.88 |
-01:05:15.4 |
HIP 59102 |
27.77 |
| 2026-08-04 12:00 |
12:07:11.99 |
-01:07:30.4 |
HIP 59102 |
29.71 |
| 2026-08-05 00:00 |
12:07:29.18 |
-01:09:45.8 |
HIP 59102 |
32.27 |
| 2026-08-05 12:00 |
12:07:46.44 |
-01:12:01.7 |
HIP 59102 |
35.33 |
| 2026-08-06 00:00 |
12:08:03.78 |
-01:14:18.0 |
HIP 59102 |
38.78 |
| 2026-08-06 12:00 |
12:08:21.19 |
-01:16:34.7 |
HIP 59102 |
42.52 |
| 2026-08-07 00:00 |
12:08:38.68 |
-01:18:51.8 |
HIP 59102 |
46.50 |
| 2026-08-07 12:00 |
12:08:56.24 |
-01:21:09.4 |
HIP 59191 |
45.23 |
| 2026-08-08 00:00 |
12:09:13.87 |
-01:23:27.3 |
HIP 59191 |
44.14 |
| 2026-08-08 12:00 |
12:09:31.57 |
-01:25:45.7 |
HIP 59491 |
42.50 |
| 2026-08-09 00:00 |
12:09:49.34 |
-01:28:04.5 |
HIP 59412 |
39.12 |
| 2026-08-09 12:00 |
12:10:07.19 |
-01:30:23.7 |
HIP 59412 |
34.83 |
| 2026-08-10 00:00 |
12:10:25.10 |
-01:32:43.3 |
HIP 59412 |
30.74 |
| 2026-08-10 12:00 |
12:10:43.08 |
-01:35:03.3 |
HIP 59412 |
26.98 |
| 2026-08-11 00:00 |
12:11:01.13 |
-01:37:23.7 |
HIP 59412 |
23.69 |
| 2026-08-11 12:00 |
12:11:19.25 |
-01:39:44.5 |
HIP 59412 |
21.12 |
| 2026-08-12 00:00 |
12:11:37.44 |
-01:42:05.6 |
HIP 59412 |
19.56 |
| 2026-08-12 12:00 |
12:11:55.69 |
-01:44:27.2 |
HIP 59412 |
19.29 |
| 2026-08-13 00:00 |
12:12:14.00 |
-01:46:49.1 |
HIP 59412 |
20.36 |
| 2026-08-13 12:00 |
12:12:32.38 |
-01:49:11.4 |
HIP 59412 |
22.59 |
| 2026-08-14 00:00 |
12:12:50.83 |
-01:51:34.0 |
HIP 59669 |
23.81 |
| 2026-08-14 12:00 |
12:13:09.34 |
-01:53:57.0 |
HIP 59669 |
21.73 |
| 2026-08-15 00:00 |
12:13:27.91 |
-01:56:20.4 |
HIP 59669 |
20.76 |
| 2026-08-15 12:00 |
12:13:46.54 |
-01:58:44.1 |
HIP 59669 |
21.09 |
| 2026-08-16 00:00 |
12:14:05.23 |
-02:01:08.1 |
HIP 59669 |
22.66 |
| 2026-08-16 12:00 |
12:14:23.99 |
-02:03:32.5 |
HIP 59669 |
25.25 |
| 2026-08-17 00:00 |
12:14:42.80 |
-02:05:57.3 |
HIP 59669 |
28.60 |
| 2026-08-17 12:00 |
12:15:01.67 |
-02:08:22.3 |
HIP 59669 |
32.48 |
| 2026-08-18 00:00 |
12:15:20.60 |
-02:10:47.7 |
HIP 59669 |
36.72 |
| 2026-08-18 12:00 |
12:15:39.58 |
-02:13:13.4 |
HIP 59872 |
35.07 |
| 2026-08-19 00:00 |
12:15:58.63 |
-02:15:39.4 |
HIP 59872 |
30.88 |