| Parameter |
Value |
| Designation |
C/2008 J6 (Hill) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2008-04-10T22:28:26.912640Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:20Z |
| Obs used |
385 |
| NEO |
- |
| M1 |
13.400 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2008-07-07.0000000 |
| e |
1.00213779 |
| q (au) |
2.003509 |
| a (au) |
-937.187180 |
| i (deg) |
44.988370 |
| Ω (om, deg) |
298.179314 |
| ω (w, deg) |
10.700067 |
| M (ma, deg) |
0.002991 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.018 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.018 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.997 |
| 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) |
| 2026-09-20 00:00 |
07:25:16.78 |
+33:24:57.4 |
HIP 36053 |
11.30 |
| 2026-09-20 12:00 |
07:25:18.25 |
+33:25:01.6 |
HIP 36053 |
11.07 |
| 2026-09-21 00:00 |
07:25:19.70 |
+33:25:05.9 |
HIP 36053 |
10.83 |
| 2026-09-21 12:00 |
07:25:21.12 |
+33:25:10.3 |
HIP 36053 |
10.61 |
| 2026-09-22 00:00 |
07:25:22.51 |
+33:25:14.7 |
HIP 36053 |
10.39 |
| 2026-09-22 12:00 |
07:25:23.87 |
+33:25:19.3 |
HIP 36053 |
10.18 |
| 2026-09-23 00:00 |
07:25:25.20 |
+33:25:23.9 |
HIP 36053 |
9.97 |
| 2026-09-23 12:00 |
07:25:26.50 |
+33:25:28.5 |
HIP 36053 |
9.77 |
| 2026-09-24 00:00 |
07:25:27.77 |
+33:25:33.3 |
HIP 36053 |
9.57 |
| 2026-09-24 12:00 |
07:25:29.02 |
+33:25:38.2 |
HIP 36053 |
9.38 |
| 2026-09-25 00:00 |
07:25:30.23 |
+33:25:43.1 |
HIP 36053 |
9.20 |
| 2026-09-25 12:00 |
07:25:31.41 |
+33:25:48.1 |
HIP 36053 |
9.02 |
| 2026-09-26 00:00 |
07:25:32.57 |
+33:25:53.2 |
HIP 36053 |
8.85 |
| 2026-09-26 12:00 |
07:25:33.69 |
+33:25:58.4 |
HIP 36053 |
8.68 |
| 2026-09-27 00:00 |
07:25:34.79 |
+33:26:03.6 |
HIP 36053 |
8.51 |
| 2026-09-27 12:00 |
07:25:35.85 |
+33:26:08.9 |
HIP 36053 |
8.36 |
| 2026-09-28 00:00 |
07:25:36.89 |
+33:26:14.3 |
HIP 36053 |
8.20 |
| 2026-09-28 12:00 |
07:25:37.89 |
+33:26:19.8 |
HIP 36053 |
8.05 |
| 2026-09-29 00:00 |
07:25:38.86 |
+33:26:25.4 |
HIP 36053 |
7.91 |
| 2026-09-29 12:00 |
07:25:39.81 |
+33:26:31.0 |
HIP 36053 |
7.76 |
| 2026-09-30 00:00 |
07:25:40.72 |
+33:26:36.7 |
HIP 36053 |
7.63 |
| 2026-09-30 12:00 |
07:25:41.60 |
+33:26:42.5 |
HIP 36053 |
7.49 |
| 2026-10-01 00:00 |
07:25:42.46 |
+33:26:48.3 |
HIP 36053 |
7.36 |
| 2026-10-01 12:00 |
07:25:43.28 |
+33:26:54.3 |
HIP 36053 |
7.23 |
| 2026-10-02 00:00 |
07:25:44.07 |
+33:27:00.3 |
HIP 36053 |
7.11 |
| 2026-10-02 12:00 |
07:25:44.83 |
+33:27:06.4 |
HIP 36053 |
6.99 |
| 2026-10-03 00:00 |
07:25:45.55 |
+33:27:12.5 |
HIP 36053 |
6.87 |
| 2026-10-03 12:00 |
07:25:46.25 |
+33:27:18.7 |
HIP 36053 |
6.75 |
| 2026-10-04 00:00 |
07:25:46.92 |
+33:27:25.0 |
HIP 36053 |
6.63 |
| 2026-10-04 12:00 |
07:25:47.55 |
+33:27:31.4 |
HIP 36053 |
6.52 |
| 2026-10-05 00:00 |
07:25:48.15 |
+33:27:37.9 |
HIP 36053 |
6.41 |
| 2026-10-05 12:00 |
07:25:48.73 |
+33:27:44.4 |
HIP 36053 |
6.30 |
| 2026-10-06 00:00 |
07:25:49.27 |
+33:27:51.0 |
HIP 36053 |
6.19 |
| 2026-10-06 12:00 |
07:25:49.77 |
+33:27:57.6 |
HIP 36053 |
6.08 |
| 2026-10-07 00:00 |
07:25:50.25 |
+33:28:04.4 |
HIP 36053 |
5.97 |
| 2026-10-07 12:00 |
07:25:50.70 |
+33:28:11.2 |
HIP 36053 |
5.86 |
| 2026-10-08 00:00 |
07:25:51.11 |
+33:28:18.0 |
HIP 36053 |
5.75 |
| 2026-10-08 12:00 |
07:25:51.49 |
+33:28:25.0 |
HIP 36053 |
5.64 |
| 2026-10-09 00:00 |
07:25:51.84 |
+33:28:32.0 |
HIP 36053 |
5.53 |
| 2026-10-09 12:00 |
07:25:52.15 |
+33:28:39.0 |
HIP 36053 |
5.42 |
| 2026-10-10 00:00 |
07:25:52.44 |
+33:28:46.2 |
HIP 36053 |
5.31 |
| 2026-10-10 12:00 |
07:25:52.69 |
+33:28:53.4 |
HIP 36053 |
5.20 |
| 2026-10-11 00:00 |
07:25:52.91 |
+33:29:00.6 |
HIP 36053 |
5.09 |