| Parameter |
Value |
| Designation |
326P/Hill |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2015-10-22T11:02:45.530880Z |
| Orbit solution date (soln_date, UTC) |
2024-06-14T15:42:23Z |
| Obs used |
301 |
| NEO |
- |
| M1 |
14.300 |
| K1 |
8.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2017-02-09.0000000 |
| e |
0.31693822 |
| q (au) |
2.779374 |
| a (au) |
4.068993 |
| i (deg) |
2.470614 |
| Ω (om, deg) |
99.811413 |
| ω (w, deg) |
278.793743 |
| M (ma, deg) |
57.103197 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.907 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.907 |
| n |
2.000 |
| gf |
0.828 |
| gb |
-0.500 |
| k |
0.946 |
| 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 |
10:24:36.40 |
+11:52:52.3 |
HIP 50802 |
36.80 |
| 2026-07-29 12:00 |
10:25:01.35 |
+11:50:27.8 |
HIP 50802 |
43.34 |
| 2026-07-30 00:00 |
10:25:26.33 |
+11:48:03.0 |
HIP 51179 |
38.93 |
| 2026-07-30 12:00 |
10:25:51.34 |
+11:45:38.0 |
HIP 51179 |
33.18 |
| 2026-07-31 00:00 |
10:26:16.38 |
+11:43:12.7 |
HIP 51179 |
27.79 |
| 2026-07-31 12:00 |
10:26:41.45 |
+11:40:47.2 |
HIP 51179 |
23.03 |
| 2026-08-01 00:00 |
10:27:06.54 |
+11:38:21.4 |
HIP 51179 |
19.38 |
| 2026-08-01 12:00 |
10:27:31.67 |
+11:35:55.3 |
HIP 51249 |
13.64 |
| 2026-08-02 00:00 |
10:27:56.82 |
+11:33:29.0 |
HIP 51249 |
8.72 |
| 2026-08-02 12:00 |
10:28:22.00 |
+11:31:02.4 |
HIP 51249 |
7.34 |
| 2026-08-03 00:00 |
10:28:47.21 |
+11:28:35.5 |
HIP 51249 |
10.95 |
| 2026-08-03 12:00 |
10:29:12.44 |
+11:26:08.4 |
HIP 51249 |
16.57 |
| 2026-08-04 00:00 |
10:29:37.70 |
+11:23:41.1 |
HIP 51249 |
22.76 |
| 2026-08-04 12:00 |
10:30:02.98 |
+11:21:13.5 |
HIP 51532 |
24.61 |
| 2026-08-05 00:00 |
10:30:28.29 |
+11:18:45.6 |
HIP 51532 |
17.97 |
| 2026-08-05 12:00 |
10:30:53.62 |
+11:16:17.6 |
HIP 51532 |
11.37 |
| 2026-08-06 00:00 |
10:31:18.97 |
+11:13:49.3 |
HIP 51532 |
4.99 |
| 2026-08-06 12:00 |
10:31:44.35 |
+11:11:20.7 |
HIP 51532 |
3.17 |
| 2026-08-07 00:00 |
10:32:09.75 |
+11:08:52.0 |
HIP 51532 |
9.22 |
| 2026-08-07 12:00 |
10:32:35.18 |
+11:06:23.0 |
HIP 51532 |
15.81 |
| 2026-08-08 00:00 |
10:33:00.62 |
+11:03:53.8 |
HIP 51532 |
22.49 |
| 2026-08-08 12:00 |
10:33:26.08 |
+11:01:24.3 |
HIP 51532 |
29.19 |
| 2026-08-09 00:00 |
10:33:51.57 |
+10:58:54.7 |
HIP 51720 |
34.70 |
| 2026-08-09 12:00 |
10:34:17.07 |
+10:56:24.8 |
HIP 51720 |
32.26 |
| 2026-08-10 00:00 |
10:34:42.60 |
+10:53:54.8 |
HIP 51945 |
30.46 |
| 2026-08-10 12:00 |
10:35:08.14 |
+10:51:24.5 |
HIP 51945 |
25.31 |
| 2026-08-11 00:00 |
10:35:33.70 |
+10:48:54.0 |
HIP 51945 |
21.07 |
| 2026-08-11 12:00 |
10:35:59.28 |
+10:46:23.4 |
HIP 51945 |
18.39 |
| 2026-08-12 00:00 |
10:36:24.87 |
+10:43:52.5 |
HIP 51997 |
14.88 |
| 2026-08-12 12:00 |
10:36:50.48 |
+10:41:21.5 |
HIP 51997 |
10.53 |
| 2026-08-13 00:00 |
10:37:16.10 |
+10:38:50.3 |
HIP 51997 |
9.60 |
| 2026-08-13 12:00 |
10:37:41.74 |
+10:36:18.9 |
HIP 51997 |
12.86 |
| 2026-08-14 00:00 |
10:38:07.40 |
+10:33:47.3 |
HIP 51997 |
18.19 |
| 2026-08-14 12:00 |
10:38:33.06 |
+10:31:15.6 |
HIP 52198 |
22.51 |
| 2026-08-15 00:00 |
10:38:58.74 |
+10:28:43.7 |
HIP 52198 |
15.82 |
| 2026-08-15 12:00 |
10:39:24.43 |
+10:26:11.6 |
HIP 52198 |
9.28 |
| 2026-08-16 00:00 |
10:39:50.14 |
+10:23:39.4 |
HIP 52198 |
3.86 |
| 2026-08-16 12:00 |
10:40:15.85 |
+10:21:07.1 |
HIP 52198 |
6.03 |
| 2026-08-17 00:00 |
10:40:41.57 |
+10:18:34.6 |
HIP 52198 |
12.28 |
| 2026-08-17 12:00 |
10:41:07.30 |
+10:16:01.9 |
HIP 52373 |
17.87 |
| 2026-08-18 00:00 |
10:41:33.05 |
+10:13:29.1 |
HIP 52373 |
13.30 |
| 2026-08-18 12:00 |
10:41:58.80 |
+10:10:56.2 |
HIP 52373 |
11.29 |
| 2026-08-19 00:00 |
10:42:24.55 |
+10:08:23.2 |
HIP 52373 |
13.09 |