| Parameter |
Value |
| Designation |
C/2010 H1 (Garradd) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2010-06-18T21:49:15.484800Z |
| Orbit solution date (soln_date, UTC) |
2022-07-06T03:12:21Z |
| Obs used |
46 |
| NEO |
- |
| M1 |
9.500 |
| K1 |
17.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2010-05-03.0000000 |
| e |
0.99965781 |
| q (au) |
2.745494 |
| a (au) |
8023.335869 |
| i (deg) |
36.531182 |
| Ω (om, deg) |
347.383773 |
| ω (w, deg) |
233.823547 |
| M (ma, deg) |
359.999936 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.811 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.811 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.996 |
| 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) |
| 2026-03-26 00:00 |
23:55:47.19 |
+12:09:20.9 |
HIP 117839 |
28.68 |
| 2026-03-26 12:00 |
23:55:50.60 |
+12:09:45.6 |
HIP 117839 |
29.60 |
| 2026-03-27 00:00 |
23:55:54.01 |
+12:10:10.4 |
HIP 117839 |
30.52 |
| 2026-03-27 12:00 |
23:55:57.41 |
+12:10:35.3 |
HIP 117839 |
31.45 |
| 2026-03-28 00:00 |
23:56:00.81 |
+12:11:00.2 |
HIP 117839 |
32.37 |
| 2026-03-28 12:00 |
23:56:04.21 |
+12:11:25.2 |
HIP 117839 |
33.29 |
| 2026-03-29 00:00 |
23:56:07.60 |
+12:11:50.3 |
HIP 117839 |
34.21 |
| 2026-03-29 12:00 |
23:56:10.99 |
+12:12:15.4 |
HIP 117839 |
35.13 |
| 2026-03-30 00:00 |
23:56:14.37 |
+12:12:40.6 |
HIP 117839 |
36.05 |
| 2026-03-30 12:00 |
23:56:17.75 |
+12:13:05.9 |
HIP 118047 |
36.57 |
| 2026-03-31 00:00 |
23:56:21.12 |
+12:13:31.2 |
HIP 118047 |
36.04 |
| 2026-03-31 12:00 |
23:56:24.49 |
+12:13:56.6 |
HIP 118047 |
35.52 |
| 2026-04-01 00:00 |
23:56:27.85 |
+12:14:22.0 |
HIP 118047 |
35.01 |
| 2026-04-01 12:00 |
23:56:31.21 |
+12:14:47.5 |
HIP 118047 |
34.52 |
| 2026-04-02 00:00 |
23:56:34.56 |
+12:15:13.1 |
HIP 118047 |
34.05 |
| 2026-04-02 12:00 |
23:56:37.90 |
+12:15:38.7 |
HIP 118047 |
33.60 |
| 2026-04-03 00:00 |
23:56:41.23 |
+12:16:04.3 |
HIP 118047 |
33.16 |
| 2026-04-03 12:00 |
23:56:44.56 |
+12:16:30.0 |
HIP 118047 |
32.75 |
| 2026-04-04 00:00 |
23:56:47.89 |
+12:16:55.8 |
HIP 118047 |
32.35 |
| 2026-04-04 12:00 |
23:56:51.20 |
+12:17:21.6 |
HIP 118047 |
31.97 |
| 2026-04-05 00:00 |
23:56:54.51 |
+12:17:47.4 |
HIP 118047 |
31.62 |
| 2026-04-05 12:00 |
23:56:57.81 |
+12:18:13.3 |
HIP 118047 |
31.29 |
| 2026-04-06 00:00 |
23:57:01.11 |
+12:18:39.2 |
HIP 118047 |
30.98 |
| 2026-04-06 12:00 |
23:57:04.39 |
+12:19:05.2 |
HIP 118047 |
30.69 |
| 2026-04-07 00:00 |
23:57:07.67 |
+12:19:31.2 |
HIP 118047 |
30.43 |
| 2026-04-07 12:00 |
23:57:10.94 |
+12:19:57.3 |
HIP 118047 |
30.19 |
| 2026-04-08 00:00 |
23:57:14.20 |
+12:20:23.4 |
HIP 118047 |
29.97 |
| 2026-04-08 12:00 |
23:57:17.45 |
+12:20:49.5 |
HIP 118047 |
29.78 |
| 2026-04-09 00:00 |
23:57:20.69 |
+12:21:15.7 |
HIP 118047 |
29.61 |
| 2026-04-09 12:00 |
23:57:23.93 |
+12:21:41.9 |
HIP 118047 |
29.47 |
| 2026-04-10 00:00 |
23:57:27.15 |
+12:22:08.1 |
HIP 118047 |
29.36 |
| 2026-04-10 12:00 |
23:57:30.37 |
+12:22:34.3 |
HIP 118047 |
29.27 |
| 2026-04-11 00:00 |
23:57:33.57 |
+12:23:00.6 |
HIP 118047 |
29.21 |
| 2026-04-11 12:00 |
23:57:36.77 |
+12:23:26.9 |
HIP 118047 |
29.17 |
| 2026-04-12 00:00 |
23:57:39.95 |
+12:23:53.3 |
HIP 118047 |
29.16 |
| 2026-04-12 12:00 |
23:57:43.13 |
+12:24:19.6 |
HIP 118047 |
29.18 |
| 2026-04-13 00:00 |
23:57:46.29 |
+12:24:46.0 |
HIP 118047 |
29.22 |
| 2026-04-13 12:00 |
23:57:49.44 |
+12:25:12.4 |
HIP 118047 |
29.28 |
| 2026-04-14 00:00 |
23:57:52.59 |
+12:25:38.9 |
HIP 118047 |
29.37 |
| 2026-04-14 12:00 |
23:57:55.72 |
+12:26:05.3 |
HIP 118047 |
29.48 |
| 2026-04-15 00:00 |
23:57:58.84 |
+12:26:31.8 |
HIP 118047 |
29.62 |
| 2026-04-15 12:00 |
23:58:01.95 |
+12:26:58.2 |
HIP 118047 |
29.78 |
| 2026-04-16 00:00 |
23:58:05.04 |
+12:27:24.7 |
HIP 118047 |
29.97 |