| Parameter |
Value |
| Designation |
P/2013 G4 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2013-02-09T16:30:18.377280Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:32Z |
| Obs used |
41 |
| NEO |
- |
| M1 |
15.100 |
| K1 |
10.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2013-04-25.0000000 |
| e |
0.41041543 |
| q (au) |
2.613194 |
| a (au) |
4.432263 |
| i (deg) |
5.925606 |
| Ω (om, deg) |
339.772839 |
| ω (w, deg) |
214.390935 |
| M (ma, deg) |
7.849220 |
Magnitude
Scatter + Global Linear
$$
M_a = (19.266 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
19.266 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.647 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
00:42:04.38 |
+07:23:24.7 |
HIP 3161 |
36.40 |
| 2026-07-29 12:00 |
00:42:02.02 |
+07:23:32.9 |
HIP 3161 |
35.87 |
| 2026-07-30 00:00 |
00:41:59.50 |
+07:23:40.1 |
HIP 3161 |
35.32 |
| 2026-07-30 12:00 |
00:41:56.83 |
+07:23:46.3 |
HIP 3161 |
34.77 |
| 2026-07-31 00:00 |
00:41:54.01 |
+07:23:51.6 |
HIP 3161 |
34.19 |
| 2026-07-31 12:00 |
00:41:51.04 |
+07:23:55.9 |
HIP 3161 |
33.61 |
| 2026-08-01 00:00 |
00:41:47.92 |
+07:23:59.3 |
HIP 3161 |
33.02 |
| 2026-08-01 12:00 |
00:41:44.65 |
+07:24:01.8 |
HIP 3161 |
32.42 |
| 2026-08-02 00:00 |
00:41:41.23 |
+07:24:03.2 |
HIP 3161 |
31.82 |
| 2026-08-02 12:00 |
00:41:37.66 |
+07:24:03.8 |
HIP 3161 |
31.22 |
| 2026-08-03 00:00 |
00:41:33.93 |
+07:24:03.3 |
HIP 3161 |
30.61 |
| 2026-08-03 12:00 |
00:41:30.06 |
+07:24:01.9 |
HIP 3161 |
30.02 |
| 2026-08-04 00:00 |
00:41:26.04 |
+07:23:59.6 |
HIP 3161 |
29.43 |
| 2026-08-04 12:00 |
00:41:21.87 |
+07:23:56.2 |
HIP 3161 |
28.86 |
| 2026-08-05 00:00 |
00:41:17.55 |
+07:23:52.0 |
HIP 3161 |
28.30 |
| 2026-08-05 12:00 |
00:41:13.07 |
+07:23:46.7 |
HIP 3161 |
27.77 |
| 2026-08-06 00:00 |
00:41:08.45 |
+07:23:40.5 |
HIP 3161 |
27.27 |
| 2026-08-06 12:00 |
00:41:03.68 |
+07:23:33.3 |
HIP 3161 |
26.80 |
| 2026-08-07 00:00 |
00:40:58.76 |
+07:23:25.1 |
HIP 3161 |
26.38 |
| 2026-08-07 12:00 |
00:40:53.69 |
+07:23:16.0 |
HIP 3161 |
26.02 |
| 2026-08-08 00:00 |
00:40:48.47 |
+07:23:05.9 |
HIP 3161 |
25.71 |
| 2026-08-08 12:00 |
00:40:43.11 |
+07:22:54.9 |
HIP 3161 |
25.47 |
| 2026-08-09 00:00 |
00:40:37.59 |
+07:22:42.8 |
HIP 3161 |
25.31 |
| 2026-08-09 12:00 |
00:40:31.93 |
+07:22:29.8 |
HIP 3161 |
25.23 |
| 2026-08-10 00:00 |
00:40:26.12 |
+07:22:15.9 |
HIP 3161 |
25.24 |
| 2026-08-10 12:00 |
00:40:20.16 |
+07:22:00.9 |
HIP 3161 |
25.35 |
| 2026-08-11 00:00 |
00:40:14.06 |
+07:21:45.0 |
HIP 3161 |
25.56 |
| 2026-08-11 12:00 |
00:40:07.81 |
+07:21:28.2 |
HIP 3161 |
25.88 |
| 2026-08-12 00:00 |
00:40:01.41 |
+07:21:10.3 |
HIP 3161 |
26.31 |
| 2026-08-12 12:00 |
00:39:54.87 |
+07:20:51.5 |
HIP 3161 |
26.86 |
| 2026-08-13 00:00 |
00:39:48.18 |
+07:20:31.8 |
HIP 3161 |
27.51 |
| 2026-08-13 12:00 |
00:39:41.35 |
+07:20:11.0 |
HIP 3161 |
28.28 |
| 2026-08-14 00:00 |
00:39:34.38 |
+07:19:49.4 |
HIP 3161 |
29.16 |
| 2026-08-14 12:00 |
00:39:27.26 |
+07:19:26.7 |
HIP 3161 |
30.14 |
| 2026-08-15 00:00 |
00:39:20.00 |
+07:19:03.1 |
HIP 3161 |
31.22 |
| 2026-08-15 12:00 |
00:39:12.60 |
+07:18:38.6 |
HIP 3161 |
32.41 |
| 2026-08-16 00:00 |
00:39:05.06 |
+07:18:13.1 |
HIP 3161 |
33.69 |
| 2026-08-16 12:00 |
00:38:57.38 |
+07:17:46.7 |
HIP 3161 |
35.05 |
| 2026-08-17 00:00 |
00:38:49.57 |
+07:17:19.3 |
HIP 3161 |
36.51 |
| 2026-08-17 12:00 |
00:38:41.61 |
+07:16:51.0 |
HIP 3161 |
38.05 |
| 2026-08-18 00:00 |
00:38:33.52 |
+07:16:21.7 |
HIP 2847 |
37.83 |
| 2026-08-18 12:00 |
00:38:25.29 |
+07:15:51.6 |
HIP 2847 |
35.73 |
| 2026-08-19 00:00 |
00:38:16.92 |
+07:15:20.5 |
HIP 2847 |
33.60 |