| Parameter |
Value |
| Designation |
P/2015 P4 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2016-01-19T00:45:47.321280Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:13Z |
| Obs used |
80 |
| NEO |
- |
| M1 |
6.500 |
| K1 |
28.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2015-09-21.0000000 |
| e |
0.58423891 |
| q (au) |
2.525162 |
| a (au) |
6.073589 |
| i (deg) |
8.713757 |
| Ω (om, deg) |
104.746924 |
| ω (w, deg) |
280.816811 |
| M (ma, deg) |
352.096266 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.240 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.240 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| k |
1.000 |
| 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 |
14:58:44.96 |
-09:30:21.6 |
HIP 73340 |
27.31 |
| 2026-07-29 12:00 |
14:58:45.34 |
-09:30:54.8 |
HIP 73340 |
26.75 |
| 2026-07-30 00:00 |
14:58:45.84 |
-09:31:28.6 |
HIP 73340 |
26.17 |
| 2026-07-30 12:00 |
14:58:46.46 |
-09:32:02.8 |
HIP 73340 |
25.58 |
| 2026-07-31 00:00 |
14:58:47.19 |
-09:32:37.5 |
HIP 73340 |
24.98 |
| 2026-07-31 12:00 |
14:58:48.03 |
-09:33:12.6 |
HIP 73340 |
24.36 |
| 2026-08-01 00:00 |
14:58:48.98 |
-09:33:48.2 |
HIP 73340 |
23.72 |
| 2026-08-01 12:00 |
14:58:50.05 |
-09:34:24.3 |
HIP 73340 |
23.07 |
| 2026-08-02 00:00 |
14:58:51.23 |
-09:35:00.9 |
HIP 73340 |
22.41 |
| 2026-08-02 12:00 |
14:58:52.53 |
-09:35:38.0 |
HIP 73340 |
21.73 |
| 2026-08-03 00:00 |
14:58:53.94 |
-09:36:15.5 |
HIP 73340 |
21.05 |
| 2026-08-03 12:00 |
14:58:55.46 |
-09:36:53.4 |
HIP 73340 |
20.34 |
| 2026-08-04 00:00 |
14:58:57.09 |
-09:37:31.9 |
HIP 73340 |
19.63 |
| 2026-08-04 12:00 |
14:58:58.84 |
-09:38:10.8 |
HIP 73340 |
18.91 |
| 2026-08-05 00:00 |
14:59:00.70 |
-09:38:50.1 |
HIP 73340 |
18.18 |
| 2026-08-05 12:00 |
14:59:02.67 |
-09:39:29.9 |
HIP 73340 |
17.44 |
| 2026-08-06 00:00 |
14:59:04.76 |
-09:40:10.2 |
HIP 73340 |
16.71 |
| 2026-08-06 12:00 |
14:59:06.96 |
-09:40:50.9 |
HIP 73340 |
15.97 |
| 2026-08-07 00:00 |
14:59:09.27 |
-09:41:32.0 |
HIP 73340 |
15.23 |
| 2026-08-07 12:00 |
14:59:11.69 |
-09:42:13.6 |
HIP 73340 |
14.51 |
| 2026-08-08 00:00 |
14:59:14.22 |
-09:42:55.6 |
HIP 73340 |
13.80 |
| 2026-08-08 12:00 |
14:59:16.87 |
-09:43:38.1 |
HIP 73340 |
13.11 |
| 2026-08-09 00:00 |
14:59:19.62 |
-09:44:21.0 |
HIP 73340 |
12.46 |
| 2026-08-09 12:00 |
14:59:22.49 |
-09:45:04.3 |
HIP 73340 |
11.85 |
| 2026-08-10 00:00 |
14:59:25.47 |
-09:45:48.1 |
HIP 73340 |
11.29 |
| 2026-08-10 12:00 |
14:59:28.57 |
-09:46:32.3 |
HIP 73340 |
10.81 |
| 2026-08-11 00:00 |
14:59:31.77 |
-09:47:16.9 |
HIP 73340 |
10.42 |
| 2026-08-11 12:00 |
14:59:35.08 |
-09:48:02.0 |
HIP 73340 |
10.15 |
| 2026-08-12 00:00 |
14:59:38.51 |
-09:48:47.4 |
HIP 73340 |
9.99 |
| 2026-08-12 12:00 |
14:59:42.04 |
-09:49:33.3 |
HIP 73340 |
9.98 |
| 2026-08-13 00:00 |
14:59:45.69 |
-09:50:19.6 |
HIP 73340 |
10.12 |
| 2026-08-13 12:00 |
14:59:49.45 |
-09:51:06.3 |
HIP 73340 |
10.42 |
| 2026-08-14 00:00 |
14:59:53.31 |
-09:51:53.4 |
HIP 73340 |
10.86 |
| 2026-08-14 12:00 |
14:59:57.28 |
-09:52:40.9 |
HIP 73340 |
11.44 |
| 2026-08-15 00:00 |
15:00:01.37 |
-09:53:28.8 |
HIP 73340 |
12.15 |
| 2026-08-15 12:00 |
15:00:05.56 |
-09:54:17.1 |
HIP 73340 |
12.97 |
| 2026-08-16 00:00 |
15:00:09.86 |
-09:55:05.7 |
HIP 73340 |
13.89 |
| 2026-08-16 12:00 |
15:00:14.27 |
-09:55:54.8 |
HIP 73340 |
14.90 |
| 2026-08-17 00:00 |
15:00:18.78 |
-09:56:44.3 |
HIP 73340 |
15.99 |
| 2026-08-17 12:00 |
15:00:23.41 |
-09:57:34.1 |
HIP 73340 |
17.15 |
| 2026-08-18 00:00 |
15:00:28.14 |
-09:58:24.3 |
HIP 73340 |
18.37 |
| 2026-08-18 12:00 |
15:00:32.97 |
-09:59:14.9 |
HIP 73340 |
19.65 |
| 2026-08-19 00:00 |
15:00:37.92 |
-10:00:05.8 |
HIP 73340 |
20.98 |