| Parameter |
Value |
| Designation |
P/2018 P4 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2018-11-07T08:17:57.094080Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:46Z |
| Obs used |
116 |
| NEO |
- |
| M1 |
11.600 |
| K1 |
10.000 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2018-08-08T12:01:59.232000Z |
| Discovery magnitude (MPC) |
20.60 w |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2018-09-13.0000000 |
| e |
0.44931114 |
| q (au) |
3.666142 |
| a (au) |
6.657375 |
| i (deg) |
23.112765 |
| Ω (om, deg) |
353.110347 |
| ω (w, deg) |
8.115551 |
| M (ma, deg) |
356.824339 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.263 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.263 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.852 |
| k |
0.999 |
| 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) |
| 2026-03-26 00:00 |
11:20:42.23 |
+05:35:41.6 |
HIP 55434 |
26.86 |
| 2026-03-26 12:00 |
11:20:32.24 |
+05:36:22.6 |
HIP 55434 |
26.92 |
| 2026-03-27 00:00 |
11:20:22.29 |
+05:37:03.2 |
HIP 55434 |
27.22 |
| 2026-03-27 12:00 |
11:20:12.37 |
+05:37:43.6 |
HIP 55434 |
27.76 |
| 2026-03-28 00:00 |
11:20:02.49 |
+05:38:23.7 |
HIP 55434 |
28.52 |
| 2026-03-28 12:00 |
11:19:52.66 |
+05:39:03.5 |
HIP 55434 |
29.48 |
| 2026-03-29 00:00 |
11:19:42.86 |
+05:39:43.0 |
HIP 55434 |
30.61 |
| 2026-03-29 12:00 |
11:19:33.11 |
+05:40:22.2 |
HIP 55323 |
31.20 |
| 2026-03-30 00:00 |
11:19:23.40 |
+05:41:01.1 |
HIP 55323 |
30.87 |
| 2026-03-30 12:00 |
11:19:13.74 |
+05:41:39.6 |
HIP 55323 |
30.75 |
| 2026-03-31 00:00 |
11:19:04.12 |
+05:42:17.9 |
HIP 55323 |
30.82 |
| 2026-03-31 12:00 |
11:18:54.55 |
+05:42:55.8 |
HIP 55323 |
31.09 |
| 2026-04-01 00:00 |
11:18:45.02 |
+05:43:33.4 |
HIP 55323 |
31.56 |
| 2026-04-01 12:00 |
11:18:35.54 |
+05:44:10.6 |
HIP 55323 |
32.20 |
| 2026-04-02 00:00 |
11:18:26.11 |
+05:44:47.6 |
HIP 55323 |
33.01 |
| 2026-04-02 12:00 |
11:18:16.74 |
+05:45:24.1 |
HIP 55323 |
33.96 |
| 2026-04-03 00:00 |
11:18:07.41 |
+05:46:00.3 |
HIP 55323 |
35.05 |
| 2026-04-03 12:00 |
11:17:58.13 |
+05:46:36.2 |
HIP 55323 |
36.27 |
| 2026-04-04 00:00 |
11:17:48.91 |
+05:47:11.7 |
HIP 55323 |
37.59 |
| 2026-04-04 12:00 |
11:17:39.75 |
+05:47:46.8 |
HIP 55323 |
39.00 |
| 2026-04-05 00:00 |
11:17:30.63 |
+05:48:21.6 |
HIP 55323 |
40.49 |
| 2026-04-05 12:00 |
11:17:21.58 |
+05:48:56.0 |
HIP 55323 |
42.05 |
| 2026-04-06 00:00 |
11:17:12.58 |
+05:49:30.0 |
HIP 54904 |
41.04 |
| 2026-04-06 12:00 |
11:17:03.63 |
+05:50:03.6 |
HIP 54904 |
38.75 |
| 2026-04-07 00:00 |
11:16:54.75 |
+05:50:36.8 |
HIP 54904 |
36.47 |
| 2026-04-07 12:00 |
11:16:45.93 |
+05:51:09.6 |
HIP 54904 |
34.21 |
| 2026-04-08 00:00 |
11:16:37.16 |
+05:51:42.0 |
HIP 54904 |
31.97 |
| 2026-04-08 12:00 |
11:16:28.46 |
+05:52:14.0 |
HIP 54904 |
29.74 |
| 2026-04-09 00:00 |
11:16:19.82 |
+05:52:45.6 |
HIP 54904 |
27.53 |
| 2026-04-09 12:00 |
11:16:11.25 |
+05:53:16.8 |
HIP 54904 |
25.33 |
| 2026-04-10 00:00 |
11:16:02.73 |
+05:53:47.6 |
HIP 54904 |
23.15 |
| 2026-04-10 12:00 |
11:15:54.29 |
+05:54:17.9 |
HIP 54904 |
20.99 |
| 2026-04-11 00:00 |
11:15:45.91 |
+05:54:47.8 |
HIP 54904 |
18.85 |
| 2026-04-11 12:00 |
11:15:37.59 |
+05:55:17.3 |
HIP 54904 |
16.73 |
| 2026-04-12 00:00 |
11:15:29.35 |
+05:55:46.3 |
HIP 54904 |
14.62 |
| 2026-04-12 12:00 |
11:15:21.17 |
+05:56:14.9 |
HIP 54904 |
12.53 |
| 2026-04-13 00:00 |
11:15:13.06 |
+05:56:43.0 |
HIP 54904 |
10.46 |
| 2026-04-13 12:00 |
11:15:05.02 |
+05:57:10.7 |
HIP 54904 |
8.42 |
| 2026-04-14 00:00 |
11:14:57.05 |
+05:57:37.9 |
HIP 54904 |
6.39 |
| 2026-04-14 12:00 |
11:14:49.16 |
+05:58:04.7 |
HIP 54904 |
4.39 |
| 2026-04-15 00:00 |
11:14:41.34 |
+05:58:31.0 |
HIP 54904 |
2.42 |
| 2026-04-15 12:00 |
11:14:33.59 |
+05:58:56.8 |
HIP 54904 |
0.67 |
| 2026-04-16 00:00 |
11:14:25.91 |
+05:59:22.1 |
HIP 54904 |
1.67 |