| Parameter |
Value |
| Designation |
186P/Garradd |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2008-05-28T23:37:34.250880Z |
| Orbit solution date (soln_date, UTC) |
2022-12-08T23:43:24Z |
| Obs used |
880 |
| NEO |
- |
| M1 |
6.500 |
| K1 |
12.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2011-08-03.0000000 |
| e |
0.12684331 |
| q (au) |
4.321945 |
| a (au) |
4.949793 |
| i (deg) |
28.544006 |
| Ω (om, deg) |
327.580045 |
| ω (w, deg) |
287.339155 |
| M (ma, deg) |
103.910997 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.628 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.628 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.829 |
| k |
0.800 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2016-05-02 |
2022-11-04 |
+52.8866 |
-34.022 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
07:30:30.22 |
+35:08:24.9 |
HIP 36412 |
12.21 |
| 2026-06-01 12:00 |
07:30:57.17 |
+35:05:56.4 |
HIP 36412 |
18.06 |
| 2026-06-02 00:00 |
07:31:24.18 |
+35:03:28.0 |
HIP 36412 |
24.02 |
| 2026-06-02 12:00 |
07:31:51.25 |
+35:00:59.6 |
HIP 36694 |
18.63 |
| 2026-06-03 00:00 |
07:32:18.38 |
+34:58:31.2 |
HIP 36694 |
13.26 |
| 2026-06-03 12:00 |
07:32:45.58 |
+34:56:02.8 |
HIP 36694 |
8.85 |
| 2026-06-04 00:00 |
07:33:12.83 |
+34:53:34.6 |
HIP 36694 |
7.46 |
| 2026-06-04 12:00 |
07:33:40.14 |
+34:51:06.3 |
HIP 36694 |
10.39 |
| 2026-06-05 00:00 |
07:34:07.52 |
+34:48:38.1 |
HIP 36694 |
15.35 |
| 2026-06-05 12:00 |
07:34:34.94 |
+34:46:09.9 |
HIP 36904 |
19.27 |
| 2026-06-06 00:00 |
07:35:02.43 |
+34:43:41.7 |
HIP 36904 |
20.05 |
| 2026-06-06 12:00 |
07:35:29.97 |
+34:41:13.6 |
HIP 36974 |
22.40 |
| 2026-06-07 00:00 |
07:35:57.57 |
+34:38:45.5 |
HIP 36974 |
19.08 |
| 2026-06-07 12:00 |
07:36:25.22 |
+34:36:17.4 |
HIP 36974 |
17.41 |
| 2026-06-08 00:00 |
07:36:52.92 |
+34:33:49.3 |
HIP 36974 |
17.88 |
| 2026-06-08 12:00 |
07:37:20.68 |
+34:31:21.3 |
HIP 37177 |
12.98 |
| 2026-06-09 00:00 |
07:37:48.49 |
+34:28:53.3 |
HIP 37177 |
6.76 |
| 2026-06-09 12:00 |
07:38:16.35 |
+34:26:25.3 |
HIP 37177 |
0.91 |
| 2026-06-10 00:00 |
07:38:44.26 |
+34:23:57.3 |
HIP 37177 |
5.85 |
| 2026-06-10 12:00 |
07:39:12.22 |
+34:21:29.4 |
HIP 37177 |
12.09 |
| 2026-06-11 00:00 |
07:39:40.23 |
+34:19:01.4 |
HIP 37265 |
17.22 |
| 2026-06-11 12:00 |
07:40:08.29 |
+34:16:33.5 |
HIP 37236 |
20.33 |
| 2026-06-12 00:00 |
07:40:36.39 |
+34:14:05.6 |
HIP 37236 |
23.89 |
| 2026-06-12 12:00 |
07:41:04.55 |
+34:11:37.7 |
HIP 37580 |
23.57 |
| 2026-06-13 00:00 |
07:41:32.74 |
+34:09:09.8 |
HIP 37580 |
17.29 |
| 2026-06-13 12:00 |
07:42:00.98 |
+34:06:42.0 |
HIP 37580 |
11.07 |
| 2026-06-14 00:00 |
07:42:29.27 |
+34:04:14.1 |
HIP 37580 |
5.16 |
| 2026-06-14 12:00 |
07:42:57.60 |
+34:01:46.2 |
HIP 37580 |
3.39 |
| 2026-06-15 00:00 |
07:43:25.97 |
+33:59:18.4 |
HIP 37580 |
8.81 |
| 2026-06-15 12:00 |
07:43:54.38 |
+33:56:50.6 |
HIP 37580 |
15.01 |
| 2026-06-16 00:00 |
07:44:22.83 |
+33:54:22.7 |
HIP 37834 |
16.17 |
| 2026-06-16 12:00 |
07:44:51.32 |
+33:51:54.9 |
HIP 37834 |
10.19 |
| 2026-06-17 00:00 |
07:45:19.85 |
+33:49:27.1 |
HIP 37834 |
5.33 |
| 2026-06-17 12:00 |
07:45:48.41 |
+33:46:59.3 |
HIP 37834 |
5.96 |
| 2026-06-18 00:00 |
07:46:17.01 |
+33:44:31.5 |
HIP 37834 |
11.20 |
| 2026-06-18 12:00 |
07:46:45.65 |
+33:42:03.7 |
HIP 38004 |
11.19 |
| 2026-06-19 00:00 |
07:47:14.32 |
+33:39:36.0 |
HIP 38004 |
5.96 |
| 2026-06-19 12:00 |
07:47:43.03 |
+33:37:08.2 |
HIP 38004 |
5.41 |
| 2026-06-20 00:00 |
07:48:11.76 |
+33:34:40.4 |
HIP 38004 |
10.33 |
| 2026-06-20 12:00 |
07:48:40.53 |
+33:32:12.7 |
HIP 38016 |
16.34 |
| 2026-06-21 00:00 |
07:49:09.33 |
+33:29:44.9 |
HIP 38016 |
21.20 |
| 2026-06-21 12:00 |
07:49:38.16 |
+33:27:17.1 |
HIP 38319 |
22.03 |
| 2026-06-22 00:00 |
07:50:07.02 |
+33:24:49.4 |
HIP 38319 |
15.82 |