| 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) |
| 2026-03-26 00:00 |
12:29:25.07 |
+10:30:03.1 |
HIP 61090 |
28.85 |
| 2026-03-26 12:00 |
12:29:14.16 |
+10:31:21.1 |
HIP 61090 |
31.82 |
| 2026-03-27 00:00 |
12:29:03.24 |
+10:32:38.6 |
HIP 61090 |
34.79 |
| 2026-03-27 12:00 |
12:28:52.33 |
+10:33:55.5 |
HIP 60943 |
35.52 |
| 2026-03-28 00:00 |
12:28:41.41 |
+10:35:12.0 |
HIP 60943 |
35.07 |
| 2026-03-28 12:00 |
12:28:30.49 |
+10:36:27.9 |
HIP 60943 |
34.88 |
| 2026-03-29 00:00 |
12:28:19.58 |
+10:37:43.3 |
HIP 60784 |
32.77 |
| 2026-03-29 12:00 |
12:28:08.66 |
+10:38:58.1 |
HIP 60784 |
30.69 |
| 2026-03-30 00:00 |
12:27:57.76 |
+10:40:12.4 |
HIP 60784 |
28.77 |
| 2026-03-30 12:00 |
12:27:46.86 |
+10:41:26.1 |
HIP 60784 |
27.05 |
| 2026-03-31 00:00 |
12:27:35.97 |
+10:42:39.3 |
HIP 60784 |
25.56 |
| 2026-03-31 12:00 |
12:27:25.08 |
+10:43:51.9 |
HIP 60784 |
24.35 |
| 2026-04-01 00:00 |
12:27:14.21 |
+10:45:03.9 |
HIP 60784 |
23.45 |
| 2026-04-01 12:00 |
12:27:03.35 |
+10:46:15.4 |
HIP 60784 |
22.90 |
| 2026-04-02 00:00 |
12:26:52.50 |
+10:47:26.2 |
HIP 60784 |
22.73 |
| 2026-04-02 12:00 |
12:26:41.67 |
+10:48:36.5 |
HIP 60784 |
22.93 |
| 2026-04-03 00:00 |
12:26:30.85 |
+10:49:46.1 |
HIP 60784 |
23.50 |
| 2026-04-03 12:00 |
12:26:20.05 |
+10:50:55.1 |
HIP 60784 |
24.40 |
| 2026-04-04 00:00 |
12:26:09.27 |
+10:52:03.5 |
HIP 60784 |
25.60 |
| 2026-04-04 12:00 |
12:25:58.51 |
+10:53:11.3 |
HIP 60784 |
27.06 |
| 2026-04-05 00:00 |
12:25:47.77 |
+10:54:18.5 |
HIP 60527 |
25.07 |
| 2026-04-05 12:00 |
12:25:37.05 |
+10:55:25.0 |
HIP 60527 |
22.35 |
| 2026-04-06 00:00 |
12:25:26.36 |
+10:56:30.8 |
HIP 60527 |
19.67 |
| 2026-04-06 12:00 |
12:25:15.69 |
+10:57:36.0 |
HIP 60527 |
17.05 |
| 2026-04-07 00:00 |
12:25:05.05 |
+10:58:40.5 |
HIP 60527 |
14.53 |
| 2026-04-07 12:00 |
12:24:54.44 |
+10:59:44.4 |
HIP 60527 |
12.16 |
| 2026-04-08 00:00 |
12:24:43.85 |
+11:00:47.6 |
HIP 60527 |
10.04 |
| 2026-04-08 12:00 |
12:24:33.30 |
+11:01:50.1 |
HIP 60527 |
8.34 |
| 2026-04-09 00:00 |
12:24:22.77 |
+11:02:51.9 |
HIP 60527 |
7.35 |
| 2026-04-09 12:00 |
12:24:12.28 |
+11:03:53.0 |
HIP 60527 |
7.35 |
| 2026-04-10 00:00 |
12:24:01.83 |
+11:04:53.4 |
HIP 60527 |
8.32 |
| 2026-04-10 12:00 |
12:23:51.41 |
+11:05:53.1 |
HIP 60527 |
9.99 |
| 2026-04-11 00:00 |
12:23:41.03 |
+11:06:52.1 |
HIP 60527 |
12.05 |
| 2026-04-11 12:00 |
12:23:30.68 |
+11:07:50.4 |
HIP 60527 |
14.32 |
| 2026-04-12 00:00 |
12:23:20.38 |
+11:08:47.9 |
HIP 60527 |
16.72 |
| 2026-04-12 12:00 |
12:23:10.12 |
+11:09:44.7 |
HIP 60527 |
19.19 |
| 2026-04-13 00:00 |
12:22:59.90 |
+11:10:40.8 |
HIP 60527 |
21.70 |
| 2026-04-13 12:00 |
12:22:49.72 |
+11:11:36.1 |
HIP 60527 |
24.24 |
| 2026-04-14 00:00 |
12:22:39.59 |
+11:12:30.7 |
HIP 60325 |
22.88 |
| 2026-04-14 12:00 |
12:22:29.50 |
+11:13:24.5 |
HIP 60325 |
21.32 |
| 2026-04-15 00:00 |
12:22:19.46 |
+11:14:17.5 |
HIP 60325 |
19.99 |
| 2026-04-15 12:00 |
12:22:09.47 |
+11:15:09.8 |
HIP 60325 |
18.95 |
| 2026-04-16 00:00 |
12:21:59.53 |
+11:16:01.3 |
HIP 60325 |
18.24 |