| Parameter |
Value |
| Designation |
386P/PANSTARRS |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2012-06-21T04:09:09.524160Z |
| Orbit solution date (soln_date, UTC) |
2021-05-31T22:43:09Z |
| Obs used |
118 |
| NEO |
- |
| M1 |
13.500 |
| K1 |
12.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2015-09-30.0000000 |
| e |
0.41776560 |
| q (au) |
2.359299 |
| a (au) |
4.052147 |
| i (deg) |
15.244307 |
| Ω (om, deg) |
134.979116 |
| ω (w, deg) |
353.350939 |
| M (ma, deg) |
144.492270 |
Magnitude
Scatter + Global Linear
$$
M_a = (16.415 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
16.415 |
| n |
2.000 |
| gf |
0.990 |
| gb |
-0.500 |
| k |
1.000 |
| δ90 |
9.998 |
| 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 |
00:10:01.21 |
-09:49:57.7 |
HIP 771 |
22.60 |
| 2026-07-29 12:00 |
00:09:58.00 |
-09:51:55.9 |
HIP 771 |
20.48 |
| 2026-07-30 00:00 |
00:09:54.60 |
-09:53:55.4 |
HIP 771 |
18.32 |
| 2026-07-30 12:00 |
00:09:51.01 |
-09:55:56.0 |
HIP 771 |
16.14 |
| 2026-07-31 00:00 |
00:09:47.22 |
-09:57:57.8 |
HIP 771 |
13.92 |
| 2026-07-31 12:00 |
00:09:43.24 |
-10:00:00.7 |
HIP 771 |
11.68 |
| 2026-08-01 00:00 |
00:09:39.07 |
-10:02:04.8 |
HIP 771 |
9.42 |
| 2026-08-01 12:00 |
00:09:34.70 |
-10:04:10.1 |
HIP 771 |
7.16 |
| 2026-08-02 00:00 |
00:09:30.14 |
-10:06:16.5 |
HIP 771 |
4.98 |
| 2026-08-02 12:00 |
00:09:25.38 |
-10:08:24.0 |
HIP 771 |
3.11 |
| 2026-08-03 00:00 |
00:09:20.44 |
-10:10:32.6 |
HIP 771 |
2.56 |
| 2026-08-03 12:00 |
00:09:15.30 |
-10:12:42.4 |
HIP 771 |
3.99 |
| 2026-08-04 00:00 |
00:09:09.96 |
-10:14:53.2 |
HIP 771 |
6.21 |
| 2026-08-04 12:00 |
00:09:04.43 |
-10:17:05.1 |
HIP 771 |
8.65 |
| 2026-08-05 00:00 |
00:08:58.71 |
-10:19:18.1 |
HIP 771 |
11.21 |
| 2026-08-05 12:00 |
00:08:52.80 |
-10:21:32.2 |
HIP 771 |
13.83 |
| 2026-08-06 00:00 |
00:08:46.70 |
-10:23:47.4 |
HIP 771 |
16.52 |
| 2026-08-06 12:00 |
00:08:40.40 |
-10:26:03.5 |
HIP 771 |
19.25 |
| 2026-08-07 00:00 |
00:08:33.91 |
-10:28:20.7 |
HIP 771 |
22.03 |
| 2026-08-07 12:00 |
00:08:27.23 |
-10:30:39.0 |
HIP 771 |
24.85 |
| 2026-08-08 00:00 |
00:08:20.36 |
-10:32:58.2 |
HIP 771 |
27.72 |
| 2026-08-08 12:00 |
00:08:13.29 |
-10:35:18.4 |
HIP 608 |
29.42 |
| 2026-08-09 00:00 |
00:08:06.04 |
-10:37:39.6 |
HIP 608 |
26.55 |
| 2026-08-09 12:00 |
00:07:58.60 |
-10:40:01.8 |
HIP 608 |
23.66 |
| 2026-08-10 00:00 |
00:07:50.97 |
-10:42:24.9 |
HIP 608 |
20.76 |
| 2026-08-10 12:00 |
00:07:43.14 |
-10:44:49.0 |
HIP 608 |
17.89 |
| 2026-08-11 00:00 |
00:07:35.14 |
-10:47:13.9 |
HIP 608 |
15.07 |
| 2026-08-11 12:00 |
00:07:26.94 |
-10:49:39.8 |
HIP 608 |
12.38 |
| 2026-08-12 00:00 |
00:07:18.56 |
-10:52:06.5 |
HIP 608 |
9.95 |
| 2026-08-12 12:00 |
00:07:09.99 |
-10:54:34.1 |
HIP 608 |
8.08 |
| 2026-08-13 00:00 |
00:07:01.24 |
-10:57:02.6 |
HIP 608 |
7.27 |
| 2026-08-13 12:00 |
00:06:52.30 |
-10:59:31.9 |
HIP 608 |
7.90 |
| 2026-08-14 00:00 |
00:06:43.19 |
-11:02:02.0 |
HIP 608 |
9.74 |
| 2026-08-14 12:00 |
00:06:33.89 |
-11:04:32.9 |
HIP 608 |
12.29 |
| 2026-08-15 00:00 |
00:06:24.41 |
-11:07:04.6 |
HIP 608 |
15.22 |
| 2026-08-15 12:00 |
00:06:14.75 |
-11:09:37.0 |
HIP 608 |
18.37 |
| 2026-08-16 00:00 |
00:06:04.92 |
-11:12:10.2 |
HIP 608 |
21.66 |
| 2026-08-16 12:00 |
00:05:54.91 |
-11:14:44.0 |
HIP 608 |
25.06 |
| 2026-08-17 00:00 |
00:05:44.72 |
-11:17:18.6 |
HIP 608 |
28.53 |
| 2026-08-17 12:00 |
00:05:34.36 |
-11:19:53.9 |
HIP 609 |
31.57 |
| 2026-08-18 00:00 |
00:05:23.82 |
-11:22:29.8 |
HIP 609 |
32.55 |
| 2026-08-18 12:00 |
00:05:13.12 |
-11:25:06.3 |
HIP 609 |
33.94 |
| 2026-08-19 00:00 |
00:05:02.25 |
-11:27:43.5 |
HIP 609 |
35.70 |