| 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) |
| 2026-07-29 00:00 |
07:20:29.65 |
+33:25:50.4 |
HIP 35526 |
13.09 |
| 2026-07-29 12:00 |
07:20:33.21 |
+33:25:45.3 |
HIP 35526 |
13.57 |
| 2026-07-30 00:00 |
07:20:36.77 |
+33:25:40.4 |
HIP 35526 |
14.08 |
| 2026-07-30 12:00 |
07:20:40.32 |
+33:25:35.5 |
HIP 35526 |
14.60 |
| 2026-07-31 00:00 |
07:20:43.86 |
+33:25:30.7 |
HIP 35526 |
15.14 |
| 2026-07-31 12:00 |
07:20:47.39 |
+33:25:25.9 |
HIP 35526 |
15.70 |
| 2026-08-01 00:00 |
07:20:50.92 |
+33:25:21.3 |
HIP 35526 |
16.26 |
| 2026-08-01 12:00 |
07:20:54.43 |
+33:25:16.7 |
HIP 35526 |
16.84 |
| 2026-08-02 00:00 |
07:20:57.93 |
+33:25:12.2 |
HIP 35526 |
17.42 |
| 2026-08-02 12:00 |
07:21:01.42 |
+33:25:07.8 |
HIP 35526 |
18.02 |
| 2026-08-03 00:00 |
07:21:04.89 |
+33:25:03.5 |
HIP 35526 |
18.62 |
| 2026-08-03 12:00 |
07:21:08.36 |
+33:24:59.3 |
HIP 35526 |
19.23 |
| 2026-08-04 00:00 |
07:21:11.82 |
+33:24:55.1 |
HIP 35748 |
19.13 |
| 2026-08-04 12:00 |
07:21:15.26 |
+33:24:51.1 |
HIP 35748 |
18.51 |
| 2026-08-05 00:00 |
07:21:18.70 |
+33:24:47.1 |
HIP 35748 |
17.91 |
| 2026-08-05 12:00 |
07:21:22.12 |
+33:24:43.2 |
HIP 35748 |
17.32 |
| 2026-08-06 00:00 |
07:21:25.53 |
+33:24:39.4 |
HIP 35748 |
16.74 |
| 2026-08-06 12:00 |
07:21:28.92 |
+33:24:35.7 |
HIP 35748 |
16.18 |
| 2026-08-07 00:00 |
07:21:32.31 |
+33:24:32.0 |
HIP 35748 |
15.63 |
| 2026-08-07 12:00 |
07:21:35.68 |
+33:24:28.5 |
HIP 35748 |
15.10 |
| 2026-08-08 00:00 |
07:21:39.04 |
+33:24:25.0 |
HIP 35748 |
14.58 |
| 2026-08-08 12:00 |
07:21:42.39 |
+33:24:21.6 |
HIP 35748 |
14.09 |
| 2026-08-09 00:00 |
07:21:45.72 |
+33:24:18.3 |
HIP 35748 |
13.61 |
| 2026-08-09 12:00 |
07:21:49.04 |
+33:24:15.1 |
HIP 35748 |
13.16 |
| 2026-08-10 00:00 |
07:21:52.34 |
+33:24:12.0 |
HIP 35748 |
12.73 |
| 2026-08-10 12:00 |
07:21:55.63 |
+33:24:08.9 |
HIP 35748 |
12.33 |
| 2026-08-11 00:00 |
07:21:58.91 |
+33:24:06.0 |
HIP 35748 |
11.96 |
| 2026-08-11 12:00 |
07:22:02.17 |
+33:24:03.1 |
HIP 35748 |
11.62 |
| 2026-08-12 00:00 |
07:22:05.42 |
+33:24:00.3 |
HIP 35748 |
11.32 |
| 2026-08-12 12:00 |
07:22:08.65 |
+33:23:57.6 |
HIP 35748 |
11.05 |
| 2026-08-13 00:00 |
07:22:11.86 |
+33:23:55.0 |
HIP 35748 |
10.81 |
| 2026-08-13 12:00 |
07:22:15.06 |
+33:23:52.5 |
HIP 35748 |
10.62 |
| 2026-08-14 00:00 |
07:22:18.25 |
+33:23:50.1 |
HIP 35748 |
10.47 |
| 2026-08-14 12:00 |
07:22:21.42 |
+33:23:47.7 |
HIP 35748 |
10.36 |
| 2026-08-15 00:00 |
07:22:24.57 |
+33:23:45.5 |
HIP 35748 |
10.29 |
| 2026-08-15 12:00 |
07:22:27.71 |
+33:23:43.3 |
HIP 35748 |
10.27 |
| 2026-08-16 00:00 |
07:22:30.83 |
+33:23:41.3 |
HIP 35748 |
10.29 |
| 2026-08-16 12:00 |
07:22:33.93 |
+33:23:39.3 |
HIP 35748 |
10.35 |
| 2026-08-17 00:00 |
07:22:37.01 |
+33:23:37.4 |
HIP 35748 |
10.45 |
| 2026-08-17 12:00 |
07:22:40.08 |
+33:23:35.6 |
HIP 35748 |
10.60 |
| 2026-08-18 00:00 |
07:22:43.13 |
+33:23:33.8 |
HIP 35748 |
10.77 |
| 2026-08-18 12:00 |
07:22:46.17 |
+33:23:32.2 |
HIP 35748 |
10.99 |
| 2026-08-19 00:00 |
07:22:49.18 |
+33:23:30.7 |
HIP 35748 |
11.23 |