| Parameter |
Value |
| Designation |
C/2008 J5 (Garradd) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2008-04-01T01:47:02.302080Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:19Z |
| Obs used |
128 |
| NEO |
- |
| M1 |
10.600 |
| K1 |
17.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2008-06-25.0000000 |
| e |
0.97288948 |
| q (au) |
1.963842 |
| a (au) |
72.438378 |
| i (deg) |
93.270724 |
| Ω (om, deg) |
287.075696 |
| ω (w, deg) |
313.376402 |
| M (ma, deg) |
0.135766 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.954 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.954 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.798 |
| k |
0.998 |
| 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 |
13:50:39.02 |
+78:25:25.0 |
HIP 67959 |
13.30 |
| 2026-09-20 12:00 |
13:50:51.36 |
+78:24:59.4 |
HIP 67959 |
12.64 |
| 2026-09-21 00:00 |
13:51:03.75 |
+78:24:34.1 |
HIP 67959 |
12.00 |
| 2026-09-21 12:00 |
13:51:16.21 |
+78:24:09.1 |
HIP 67959 |
11.36 |
| 2026-09-22 00:00 |
13:51:28.71 |
+78:23:44.5 |
HIP 67959 |
10.74 |
| 2026-09-22 12:00 |
13:51:41.28 |
+78:23:20.2 |
HIP 67959 |
10.13 |
| 2026-09-23 00:00 |
13:51:53.89 |
+78:22:56.2 |
HIP 67959 |
9.53 |
| 2026-09-23 12:00 |
13:52:06.56 |
+78:22:32.6 |
HIP 67959 |
8.96 |
| 2026-09-24 00:00 |
13:52:19.29 |
+78:22:09.3 |
HIP 67959 |
8.41 |
| 2026-09-24 12:00 |
13:52:32.06 |
+78:21:46.3 |
HIP 67959 |
7.88 |
| 2026-09-25 00:00 |
13:52:44.89 |
+78:21:23.7 |
HIP 67959 |
7.39 |
| 2026-09-25 12:00 |
13:52:57.76 |
+78:21:01.4 |
HIP 67959 |
6.94 |
| 2026-09-26 00:00 |
13:53:10.69 |
+78:20:39.5 |
HIP 67959 |
6.53 |
| 2026-09-26 12:00 |
13:53:23.66 |
+78:20:17.8 |
HIP 67959 |
6.19 |
| 2026-09-27 00:00 |
13:53:36.68 |
+78:19:56.6 |
HIP 67959 |
5.91 |
| 2026-09-27 12:00 |
13:53:49.75 |
+78:19:35.7 |
HIP 67959 |
5.72 |
| 2026-09-28 00:00 |
13:54:02.87 |
+78:19:15.1 |
HIP 67959 |
5.60 |
| 2026-09-28 12:00 |
13:54:16.04 |
+78:18:54.8 |
HIP 67959 |
5.58 |
| 2026-09-29 00:00 |
13:54:29.25 |
+78:18:34.9 |
HIP 67959 |
5.66 |
| 2026-09-29 12:00 |
13:54:42.50 |
+78:18:15.4 |
HIP 67959 |
5.82 |
| 2026-09-30 00:00 |
13:54:55.80 |
+78:17:56.2 |
HIP 67959 |
6.06 |
| 2026-09-30 12:00 |
13:55:09.14 |
+78:17:37.4 |
HIP 67959 |
6.37 |
| 2026-10-01 00:00 |
13:55:22.53 |
+78:17:18.9 |
HIP 67959 |
6.75 |
| 2026-10-01 12:00 |
13:55:35.96 |
+78:17:00.7 |
HIP 67959 |
7.18 |
| 2026-10-02 00:00 |
13:55:49.43 |
+78:16:43.0 |
HIP 67959 |
7.65 |
| 2026-10-02 12:00 |
13:56:02.95 |
+78:16:25.5 |
HIP 67959 |
8.16 |
| 2026-10-03 00:00 |
13:56:16.50 |
+78:16:08.5 |
HIP 67959 |
8.70 |
| 2026-10-03 12:00 |
13:56:30.09 |
+78:15:51.8 |
HIP 67959 |
9.26 |
| 2026-10-04 00:00 |
13:56:43.73 |
+78:15:35.4 |
HIP 67959 |
9.84 |
| 2026-10-04 12:00 |
13:56:57.40 |
+78:15:19.4 |
HIP 67959 |
10.44 |
| 2026-10-05 00:00 |
13:57:11.11 |
+78:15:03.8 |
HIP 67959 |
11.05 |
| 2026-10-05 12:00 |
13:57:24.86 |
+78:14:48.5 |
HIP 67959 |
11.67 |
| 2026-10-06 00:00 |
13:57:38.64 |
+78:14:33.6 |
HIP 67959 |
12.31 |
| 2026-10-06 12:00 |
13:57:52.46 |
+78:14:19.1 |
HIP 67959 |
12.95 |
| 2026-10-07 00:00 |
13:58:06.31 |
+78:14:05.0 |
HIP 67959 |
13.60 |
| 2026-10-07 12:00 |
13:58:20.20 |
+78:13:51.2 |
HIP 67959 |
14.25 |
| 2026-10-08 00:00 |
13:58:34.13 |
+78:13:37.8 |
HIP 67959 |
14.91 |
| 2026-10-08 12:00 |
13:58:48.08 |
+78:13:24.7 |
HIP 67959 |
15.58 |
| 2026-10-09 00:00 |
13:59:02.07 |
+78:13:12.0 |
HIP 67959 |
16.25 |
| 2026-10-09 12:00 |
13:59:16.09 |
+78:12:59.7 |
HIP 68719 |
16.62 |
| 2026-10-10 00:00 |
13:59:30.13 |
+78:12:47.8 |
HIP 68719 |
15.89 |
| 2026-10-10 12:00 |
13:59:44.21 |
+78:12:36.3 |
HIP 68719 |
15.17 |
| 2026-10-11 00:00 |
13:59:58.32 |
+78:12:25.1 |
HIP 68719 |
14.45 |