| Parameter |
Value |
| Designation |
P/2020 S1 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2021-01-16T21:13:40.255680Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:34:12Z |
| Obs used |
33 |
| NEO |
- |
| M1 |
17.500 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2020-09-16T09:59:30.048000Z |
| Discovery magnitude (MPC) |
21.70 w |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2020-09-10.0000000 |
| e |
0.50722330 |
| q (au) |
2.947362 |
| a (au) |
5.981132 |
| i (deg) |
13.733881 |
| Ω (om, deg) |
129.458525 |
| ω (w, deg) |
254.866187 |
| M (ma, deg) |
351.315802 |
Magnitude
Scatter + Global Linear
$$
M_a = (16.347 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
16.347 |
| n |
2.000 |
| 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 |
12:20:16.44 |
+09:40:49.6 |
HIP 60154 |
12.88 |
| 2026-07-29 12:00 |
12:20:25.63 |
+09:39:25.5 |
HIP 60154 |
14.76 |
| 2026-07-30 00:00 |
12:20:34.89 |
+09:38:01.1 |
HIP 60154 |
16.87 |
| 2026-07-30 12:00 |
12:20:44.22 |
+09:36:36.4 |
HIP 60154 |
19.13 |
| 2026-07-31 00:00 |
12:20:53.62 |
+09:35:11.5 |
HIP 60154 |
21.51 |
| 2026-07-31 12:00 |
12:21:03.09 |
+09:33:46.4 |
HIP 60154 |
23.97 |
| 2026-08-01 00:00 |
12:21:12.63 |
+09:32:21.0 |
HIP 60154 |
26.49 |
| 2026-08-01 12:00 |
12:21:22.23 |
+09:30:55.4 |
HIP 60154 |
29.07 |
| 2026-08-02 00:00 |
12:21:31.91 |
+09:29:29.6 |
HIP 60345 |
29.77 |
| 2026-08-02 12:00 |
12:21:41.65 |
+09:28:03.5 |
HIP 60345 |
30.21 |
| 2026-08-03 00:00 |
12:21:51.45 |
+09:26:37.2 |
HIP 60345 |
30.89 |
| 2026-08-03 12:00 |
12:22:01.32 |
+09:25:10.7 |
HIP 60345 |
31.80 |
| 2026-08-04 00:00 |
12:22:11.26 |
+09:23:44.0 |
HIP 60509 |
31.61 |
| 2026-08-04 12:00 |
12:22:21.27 |
+09:22:17.0 |
HIP 60509 |
29.57 |
| 2026-08-05 00:00 |
12:22:31.33 |
+09:20:49.9 |
HIP 60509 |
27.67 |
| 2026-08-05 12:00 |
12:22:41.47 |
+09:19:22.6 |
HIP 60509 |
25.93 |
| 2026-08-06 00:00 |
12:22:51.66 |
+09:17:55.0 |
HIP 60509 |
24.40 |
| 2026-08-06 12:00 |
12:23:01.92 |
+09:16:27.3 |
HIP 60509 |
23.13 |
| 2026-08-07 00:00 |
12:23:12.24 |
+09:14:59.3 |
HIP 60509 |
22.16 |
| 2026-08-07 12:00 |
12:23:22.63 |
+09:13:31.2 |
HIP 60509 |
21.54 |
| 2026-08-08 00:00 |
12:23:33.08 |
+09:12:02.9 |
HIP 60509 |
21.32 |
| 2026-08-08 12:00 |
12:23:43.59 |
+09:10:34.4 |
HIP 60509 |
21.50 |
| 2026-08-09 00:00 |
12:23:54.16 |
+09:09:05.8 |
HIP 60509 |
22.08 |
| 2026-08-09 12:00 |
12:24:04.79 |
+09:07:36.9 |
HIP 60509 |
23.05 |
| 2026-08-10 00:00 |
12:24:15.48 |
+09:06:07.9 |
HIP 60509 |
24.35 |
| 2026-08-10 12:00 |
12:24:26.23 |
+09:04:38.8 |
HIP 60509 |
25.95 |
| 2026-08-11 00:00 |
12:24:37.04 |
+09:03:09.4 |
HIP 60509 |
27.79 |
| 2026-08-11 12:00 |
12:24:47.91 |
+09:01:40.0 |
HIP 60509 |
29.84 |
| 2026-08-12 00:00 |
12:24:58.84 |
+09:00:10.3 |
HIP 60754 |
30.74 |
| 2026-08-12 12:00 |
12:25:09.83 |
+08:58:40.6 |
HIP 60754 |
27.96 |
| 2026-08-13 00:00 |
12:25:20.87 |
+08:57:10.6 |
HIP 60754 |
25.25 |
| 2026-08-13 12:00 |
12:25:31.97 |
+08:55:40.6 |
HIP 60754 |
22.63 |
| 2026-08-14 00:00 |
12:25:43.12 |
+08:54:10.4 |
HIP 60754 |
20.13 |
| 2026-08-14 12:00 |
12:25:54.33 |
+08:52:40.1 |
HIP 60754 |
17.83 |
| 2026-08-15 00:00 |
12:26:05.60 |
+08:51:09.7 |
HIP 60754 |
15.81 |
| 2026-08-15 12:00 |
12:26:16.92 |
+08:49:39.1 |
HIP 60754 |
14.21 |
| 2026-08-16 00:00 |
12:26:28.29 |
+08:48:08.4 |
HIP 60754 |
13.18 |
| 2026-08-16 12:00 |
12:26:39.72 |
+08:46:37.7 |
HIP 60754 |
12.88 |
| 2026-08-17 00:00 |
12:26:51.20 |
+08:45:06.8 |
HIP 60754 |
13.36 |
| 2026-08-17 12:00 |
12:27:02.73 |
+08:43:35.8 |
HIP 60804 |
11.97 |
| 2026-08-18 00:00 |
12:27:14.31 |
+08:42:04.7 |
HIP 60804 |
8.77 |
| 2026-08-18 12:00 |
12:27:25.95 |
+08:40:33.6 |
HIP 60804 |
5.60 |
| 2026-08-19 00:00 |
12:27:37.63 |
+08:39:02.3 |
HIP 60804 |
2.65 |