P/2020 S1 (PANSTARRS)
| 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 |
-0.905 |
| 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) |
| 2026-02-03 00:00 |
12:43:36.67 |
+08:05:15.8 |
HIP 62165 |
13.16 |
| 2026-02-03 12:00 |
12:43:32.69 |
+08:06:30.4 |
HIP 62165 |
14.59 |
| 2026-02-04 00:00 |
12:43:28.61 |
+08:07:45.4 |
HIP 62165 |
16.07 |
| 2026-02-04 12:00 |
12:43:24.41 |
+08:09:00.9 |
HIP 62165 |
17.60 |
| 2026-02-05 00:00 |
12:43:20.11 |
+08:10:17.0 |
HIP 61990 |
17.67 |
| 2026-02-05 12:00 |
12:43:15.69 |
+08:11:33.5 |
HIP 61990 |
17.33 |
| 2026-02-06 00:00 |
12:43:11.16 |
+08:12:50.6 |
HIP 61990 |
17.12 |
| 2026-02-06 12:00 |
12:43:06.52 |
+08:14:08.1 |
HIP 61990 |
17.07 |
| 2026-02-07 00:00 |
12:43:01.78 |
+08:15:26.1 |
HIP 61990 |
17.18 |
| 2026-02-07 12:00 |
12:42:56.92 |
+08:16:44.6 |
HIP 61990 |
17.46 |
| 2026-02-08 00:00 |
12:42:51.96 |
+08:18:03.5 |
HIP 61990 |
17.91 |
| 2026-02-08 12:00 |
12:42:46.88 |
+08:19:22.9 |
HIP 61990 |
18.51 |
| 2026-02-09 00:00 |
12:42:41.70 |
+08:20:42.7 |
HIP 61990 |
19.27 |
| 2026-02-09 12:00 |
12:42:36.42 |
+08:22:03.0 |
HIP 61990 |
20.17 |
| 2026-02-10 00:00 |
12:42:31.02 |
+08:23:23.7 |
HIP 61990 |
21.20 |
| 2026-02-10 12:00 |
12:42:25.52 |
+08:24:44.8 |
HIP 61990 |
22.35 |
| 2026-02-11 00:00 |
12:42:19.92 |
+08:26:06.3 |
HIP 61990 |
23.60 |
| 2026-02-11 12:00 |
12:42:14.21 |
+08:27:28.2 |
HIP 61990 |
24.95 |
| 2026-02-12 00:00 |
12:42:08.39 |
+08:28:50.5 |
HIP 61990 |
26.38 |
| 2026-02-12 12:00 |
12:42:02.47 |
+08:30:13.3 |
HIP 61889 |
25.83 |
| 2026-02-13 00:00 |
12:41:56.45 |
+08:31:36.3 |
HIP 61889 |
23.81 |
| 2026-02-13 12:00 |
12:41:50.33 |
+08:32:59.8 |
HIP 61889 |
21.77 |
| 2026-02-14 00:00 |
12:41:44.11 |
+08:34:23.6 |
HIP 61889 |
19.72 |
| 2026-02-14 12:00 |
12:41:37.78 |
+08:35:47.7 |
HIP 61889 |
17.65 |
| 2026-02-15 00:00 |
12:41:31.35 |
+08:37:12.2 |
HIP 61889 |
15.57 |
| 2026-02-15 12:00 |
12:41:24.83 |
+08:38:37.0 |
HIP 61889 |
13.48 |
| 2026-02-16 00:00 |
12:41:18.20 |
+08:40:02.2 |
HIP 61889 |
11.40 |
| 2026-02-16 12:00 |
12:41:11.48 |
+08:41:27.6 |
HIP 61889 |
9.34 |
| 2026-02-17 00:00 |
12:41:04.66 |
+08:42:53.4 |
HIP 61889 |
7.35 |
| 2026-02-17 12:00 |
12:40:57.75 |
+08:44:19.4 |
HIP 61889 |
5.51 |
| 2026-02-18 00:00 |
12:40:50.73 |
+08:45:45.7 |
HIP 61889 |
4.09 |
| 2026-02-18 12:00 |
12:40:43.63 |
+08:47:12.3 |
HIP 61889 |
3.65 |
| 2026-02-19 00:00 |
12:40:36.43 |
+08:48:39.1 |
HIP 61889 |
4.52 |
| 2026-02-19 12:00 |
12:40:29.14 |
+08:50:06.2 |
HIP 61889 |
6.19 |
| 2026-02-20 00:00 |
12:40:21.75 |
+08:51:33.5 |
HIP 61889 |
8.20 |
| 2026-02-20 12:00 |
12:40:14.28 |
+08:53:01.0 |
HIP 61889 |
10.37 |
| 2026-02-21 00:00 |
12:40:06.72 |
+08:54:28.8 |
HIP 61889 |
12.63 |
| 2026-02-21 12:00 |
12:39:59.06 |
+08:55:56.7 |
HIP 61889 |
14.94 |
| 2026-02-22 00:00 |
12:39:51.32 |
+08:57:24.9 |
HIP 61889 |
17.30 |
| 2026-02-22 12:00 |
12:39:43.49 |
+08:58:53.2 |
HIP 61889 |
19.69 |
| 2026-02-23 00:00 |
12:39:35.58 |
+09:00:21.7 |
HIP 61889 |
22.11 |
| 2026-02-23 12:00 |
12:39:27.58 |
+09:01:50.3 |
HIP 61889 |
24.55 |
| 2026-02-24 00:00 |
12:39:19.50 |
+09:03:19.2 |
HIP 61889 |
27.02 |