| Parameter |
Value |
| Designation |
C/2014 F1 (Hill) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2013-10-04T20:00:02.148480Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:50Z |
| Obs used |
190 |
| NEO |
- |
| M1 |
13.700 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2014-04-19.0000000 |
| e |
0.99907518 |
| q (au) |
3.496337 |
| a (au) |
3780.558013 |
| i (deg) |
108.253050 |
| Ω (om, deg) |
239.902413 |
| ω (w, deg) |
8.242943 |
| M (ma, deg) |
0.000832 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.874 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.874 |
| n |
2.000 |
| gf |
0.801 |
| gb |
-0.500 |
| k |
1.000 |
| 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 |
04:24:27.84 |
+52:48:31.3 |
HIP 20760 |
22.06 |
| 2026-07-29 12:00 |
04:24:31.20 |
+52:48:57.3 |
HIP 20760 |
21.50 |
| 2026-07-30 00:00 |
04:24:34.51 |
+52:49:23.3 |
HIP 20760 |
20.95 |
| 2026-07-30 12:00 |
04:24:37.77 |
+52:49:49.5 |
HIP 20760 |
20.42 |
| 2026-07-31 00:00 |
04:24:40.99 |
+52:50:15.7 |
HIP 20760 |
19.90 |
| 2026-07-31 12:00 |
04:24:44.17 |
+52:50:42.0 |
HIP 20760 |
19.40 |
| 2026-08-01 00:00 |
04:24:47.29 |
+52:51:08.4 |
HIP 20760 |
18.91 |
| 2026-08-01 12:00 |
04:24:50.37 |
+52:51:34.8 |
HIP 20760 |
18.44 |
| 2026-08-02 00:00 |
04:24:53.40 |
+52:52:01.3 |
HIP 20760 |
17.99 |
| 2026-08-02 12:00 |
04:24:56.38 |
+52:52:27.9 |
HIP 20760 |
17.56 |
| 2026-08-03 00:00 |
04:24:59.31 |
+52:52:54.6 |
HIP 20760 |
17.15 |
| 2026-08-03 12:00 |
04:25:02.20 |
+52:53:21.3 |
HIP 20760 |
16.76 |
| 2026-08-04 00:00 |
04:25:05.03 |
+52:53:48.1 |
HIP 20760 |
16.39 |
| 2026-08-04 12:00 |
04:25:07.82 |
+52:54:15.0 |
HIP 20760 |
16.04 |
| 2026-08-05 00:00 |
04:25:10.55 |
+52:54:41.9 |
HIP 20760 |
15.72 |
| 2026-08-05 12:00 |
04:25:13.24 |
+52:55:08.8 |
HIP 20760 |
15.42 |
| 2026-08-06 00:00 |
04:25:15.88 |
+52:55:35.9 |
HIP 20760 |
15.15 |
| 2026-08-06 12:00 |
04:25:18.46 |
+52:56:03.0 |
HIP 20760 |
14.90 |
| 2026-08-07 00:00 |
04:25:21.00 |
+52:56:30.1 |
HIP 20760 |
14.69 |
| 2026-08-07 12:00 |
04:25:23.48 |
+52:56:57.3 |
HIP 20760 |
14.50 |
| 2026-08-08 00:00 |
04:25:25.92 |
+52:57:24.5 |
HIP 20760 |
14.34 |
| 2026-08-08 12:00 |
04:25:28.30 |
+52:57:51.8 |
HIP 20760 |
14.21 |
| 2026-08-09 00:00 |
04:25:30.63 |
+52:58:19.2 |
HIP 20760 |
14.11 |
| 2026-08-09 12:00 |
04:25:32.91 |
+52:58:46.6 |
HIP 20760 |
14.04 |
| 2026-08-10 00:00 |
04:25:35.13 |
+52:59:14.0 |
HIP 20760 |
14.00 |
| 2026-08-10 12:00 |
04:25:37.31 |
+52:59:41.4 |
HIP 20760 |
13.99 |
| 2026-08-11 00:00 |
04:25:39.43 |
+53:00:08.9 |
HIP 20760 |
14.01 |
| 2026-08-11 12:00 |
04:25:41.49 |
+53:00:36.5 |
HIP 20760 |
14.06 |
| 2026-08-12 00:00 |
04:25:43.51 |
+53:01:04.0 |
HIP 20760 |
14.14 |
| 2026-08-12 12:00 |
04:25:45.47 |
+53:01:31.6 |
HIP 20760 |
14.24 |
| 2026-08-13 00:00 |
04:25:47.37 |
+53:01:59.2 |
HIP 20760 |
14.37 |
| 2026-08-13 12:00 |
04:25:49.23 |
+53:02:26.9 |
HIP 20760 |
14.53 |
| 2026-08-14 00:00 |
04:25:51.02 |
+53:02:54.6 |
HIP 20760 |
14.71 |
| 2026-08-14 12:00 |
04:25:52.77 |
+53:03:22.2 |
HIP 20760 |
14.91 |
| 2026-08-15 00:00 |
04:25:54.46 |
+53:03:50.0 |
HIP 20760 |
15.13 |
| 2026-08-15 12:00 |
04:25:56.09 |
+53:04:17.7 |
HIP 20760 |
15.37 |
| 2026-08-16 00:00 |
04:25:57.67 |
+53:04:45.4 |
HIP 20760 |
15.63 |
| 2026-08-16 12:00 |
04:25:59.19 |
+53:05:13.2 |
HIP 20760 |
15.91 |
| 2026-08-17 00:00 |
04:26:00.66 |
+53:05:40.9 |
HIP 20760 |
16.20 |
| 2026-08-17 12:00 |
04:26:02.07 |
+53:06:08.7 |
HIP 20760 |
16.51 |
| 2026-08-18 00:00 |
04:26:03.43 |
+53:06:36.5 |
HIP 20760 |
16.83 |
| 2026-08-18 12:00 |
04:26:04.73 |
+53:07:04.2 |
HIP 20760 |
17.16 |
| 2026-08-19 00:00 |
04:26:05.98 |
+53:07:32.0 |
HIP 20760 |
17.51 |