| Parameter |
Value |
| Designation |
259P/Garradd |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2013-01-25T10:23:26.102400Z |
| Orbit solution date (soln_date, UTC) |
2026-07-16T19:12:28Z |
| Obs used |
75 |
| NEO |
- |
| M1 |
14.100 |
| K1 |
21.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2012-02-18.0000000 |
| e |
0.34116076 |
| q (au) |
1.797413 |
| a (au) |
2.728150 |
| i (deg) |
15.899246 |
| Ω (om, deg) |
51.961498 |
| ω (w, deg) |
256.571095 |
| M (ma, deg) |
285.100808 |
Magnitude
Scatter + Global Linear
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
20:29:58.47 |
-52:30:02.1 |
HIP 101001 |
13.58 |
| 2026-07-29 12:00 |
20:29:34.84 |
-52:32:21.4 |
HIP 101001 |
11.94 |
| 2026-07-30 00:00 |
20:29:11.23 |
-52:34:32.5 |
HIP 101001 |
11.61 |
| 2026-07-30 12:00 |
20:28:47.67 |
-52:36:35.4 |
HIP 101001 |
12.61 |
| 2026-07-31 00:00 |
20:28:24.16 |
-52:38:30.1 |
HIP 101001 |
14.60 |
| 2026-07-31 12:00 |
20:28:00.72 |
-52:40:16.4 |
HIP 101001 |
17.19 |
| 2026-08-01 00:00 |
20:27:37.38 |
-52:41:54.6 |
HIP 101001 |
20.11 |
| 2026-08-01 12:00 |
20:27:14.16 |
-52:43:24.4 |
HIP 101001 |
23.20 |
| 2026-08-02 00:00 |
20:26:51.06 |
-52:44:46.0 |
HIP 100752 |
24.34 |
| 2026-08-02 12:00 |
20:26:28.11 |
-52:45:59.3 |
HIP 100752 |
21.85 |
| 2026-08-03 00:00 |
20:26:05.33 |
-52:47:04.4 |
HIP 100752 |
19.88 |
| 2026-08-03 12:00 |
20:25:42.74 |
-52:48:01.2 |
HIP 100752 |
18.55 |
| 2026-08-04 00:00 |
20:25:20.35 |
-52:48:49.7 |
HIP 100627 |
16.51 |
| 2026-08-04 12:00 |
20:24:58.17 |
-52:49:30.0 |
HIP 100627 |
14.17 |
| 2026-08-05 00:00 |
20:24:36.24 |
-52:50:02.1 |
HIP 100627 |
12.48 |
| 2026-08-05 12:00 |
20:24:14.56 |
-52:50:25.9 |
HIP 100627 |
11.67 |
| 2026-08-06 00:00 |
20:23:53.15 |
-52:50:41.6 |
HIP 100627 |
11.88 |
| 2026-08-06 12:00 |
20:23:32.03 |
-52:50:49.1 |
HIP 100627 |
13.02 |
| 2026-08-07 00:00 |
20:23:11.23 |
-52:50:48.4 |
HIP 100627 |
14.84 |
| 2026-08-07 12:00 |
20:22:50.74 |
-52:50:39.6 |
HIP 100627 |
17.10 |
| 2026-08-08 00:00 |
20:22:30.60 |
-52:50:22.7 |
HIP 100627 |
19.63 |
| 2026-08-08 12:00 |
20:22:10.82 |
-52:49:57.8 |
HIP 100627 |
22.32 |
| 2026-08-09 00:00 |
20:21:51.41 |
-52:49:24.8 |
HIP 100189 |
24.92 |
| 2026-08-09 12:00 |
20:21:32.39 |
-52:48:43.8 |
HIP 100189 |
22.63 |
| 2026-08-10 00:00 |
20:21:13.79 |
-52:47:54.9 |
HIP 100189 |
20.63 |
| 2026-08-10 12:00 |
20:20:55.60 |
-52:46:58.0 |
HIP 100189 |
19.00 |
| 2026-08-11 00:00 |
20:20:37.86 |
-52:45:53.3 |
HIP 100189 |
17.85 |
| 2026-08-11 12:00 |
20:20:20.57 |
-52:44:40.8 |
HIP 100137 |
16.07 |
| 2026-08-12 00:00 |
20:20:03.75 |
-52:43:20.5 |
HIP 100137 |
13.19 |
| 2026-08-12 12:00 |
20:19:47.42 |
-52:41:52.5 |
HIP 100137 |
10.32 |
| 2026-08-13 00:00 |
20:19:31.59 |
-52:40:16.9 |
HIP 100137 |
7.46 |
| 2026-08-13 12:00 |
20:19:16.27 |
-52:38:33.7 |
HIP 100137 |
4.66 |
| 2026-08-14 00:00 |
20:19:01.47 |
-52:36:43.0 |
HIP 100137 |
2.20 |
| 2026-08-14 12:00 |
20:18:47.21 |
-52:34:44.8 |
HIP 100137 |
2.32 |
| 2026-08-15 00:00 |
20:18:33.50 |
-52:32:39.3 |
HIP 100137 |
4.88 |
| 2026-08-15 12:00 |
20:18:20.35 |
-52:30:26.4 |
HIP 100137 |
7.78 |
| 2026-08-16 00:00 |
20:18:07.77 |
-52:28:06.3 |
HIP 100137 |
10.78 |
| 2026-08-16 12:00 |
20:17:55.78 |
-52:25:39.1 |
HIP 100137 |
13.84 |
| 2026-08-17 00:00 |
20:17:44.37 |
-52:23:04.8 |
HIP 100137 |
16.94 |
| 2026-08-17 12:00 |
20:17:33.56 |
-52:20:23.5 |
HIP 100207 |
20.05 |
| 2026-08-18 00:00 |
20:17:23.36 |
-52:17:35.2 |
HIP 100207 |
20.31 |
| 2026-08-18 12:00 |
20:17:13.78 |
-52:14:40.2 |
HIP 100035 |
20.19 |
| 2026-08-19 00:00 |
20:17:04.81 |
-52:11:38.4 |
HIP 100035 |
17.68 |