| Parameter |
Value |
| Designation |
P/2019 S2 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2019-02-20T19:57:11.050560Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:59Z |
| Obs used |
29 |
| NEO |
- |
| M1 |
13.100 |
| K1 |
10.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-09-28T08:58:56.064000Z |
| Discovery magnitude (MPC) |
21.60 w |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2019-09-12.0000000 |
| e |
0.20666395 |
| q (au) |
3.755253 |
| a (au) |
4.733496 |
| i (deg) |
10.472992 |
| Ω (om, deg) |
93.123709 |
| ω (w, deg) |
216.744948 |
| M (ma, deg) |
19.444094 |
Magnitude
Scatter + Global Linear
$$
M_a = (16.456 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
16.456 |
| n |
2.000 |
| gf |
0.804 |
| gb |
-0.500 |
| k |
0.858 |
| δ90 |
1.000 |
| 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 |
12:07:27.06 |
+13:10:05.8 |
HIP 59126 |
8.11 |
| 2026-03-26 12:00 |
12:07:11.62 |
+13:11:38.0 |
HIP 59126 |
10.49 |
| 2026-03-27 00:00 |
12:06:56.20 |
+13:13:09.2 |
HIP 59126 |
13.68 |
| 2026-03-27 12:00 |
12:06:40.79 |
+13:14:39.3 |
HIP 59099 |
17.16 |
| 2026-03-28 00:00 |
12:06:25.41 |
+13:16:08.4 |
HIP 59099 |
20.28 |
| 2026-03-28 12:00 |
12:06:10.05 |
+13:17:36.5 |
HIP 58943 |
18.20 |
| 2026-03-29 00:00 |
12:05:54.71 |
+13:19:03.4 |
HIP 58943 |
14.37 |
| 2026-03-29 12:00 |
12:05:39.40 |
+13:20:29.3 |
HIP 58943 |
10.69 |
| 2026-03-30 00:00 |
12:05:24.13 |
+13:21:54.1 |
HIP 58943 |
7.36 |
| 2026-03-30 12:00 |
12:05:08.88 |
+13:23:17.7 |
HIP 58943 |
5.09 |
| 2026-03-31 00:00 |
12:04:53.68 |
+13:24:40.2 |
HIP 58943 |
5.38 |
| 2026-03-31 12:00 |
12:04:38.51 |
+13:26:01.6 |
HIP 58943 |
7.94 |
| 2026-04-01 00:00 |
12:04:23.38 |
+13:27:21.8 |
HIP 58943 |
11.31 |
| 2026-04-01 12:00 |
12:04:08.30 |
+13:28:40.9 |
HIP 58943 |
14.93 |
| 2026-04-02 00:00 |
12:03:53.26 |
+13:29:58.8 |
HIP 58943 |
18.65 |
| 2026-04-02 12:00 |
12:03:38.28 |
+13:31:15.5 |
HIP 58943 |
22.41 |
| 2026-04-03 00:00 |
12:03:23.34 |
+13:32:31.0 |
HIP 58663 |
25.22 |
| 2026-04-03 12:00 |
12:03:08.46 |
+13:33:45.3 |
HIP 58663 |
22.29 |
| 2026-04-04 00:00 |
12:02:53.63 |
+13:34:58.3 |
HIP 58663 |
19.67 |
| 2026-04-04 12:00 |
12:02:38.86 |
+13:36:10.2 |
HIP 58663 |
17.49 |
| 2026-04-05 00:00 |
12:02:24.15 |
+13:37:20.8 |
HIP 58663 |
15.92 |
| 2026-04-05 12:00 |
12:02:09.51 |
+13:38:30.1 |
HIP 58663 |
15.12 |
| 2026-04-06 00:00 |
12:01:54.93 |
+13:39:38.2 |
HIP 58594 |
14.31 |
| 2026-04-06 12:00 |
12:01:40.43 |
+13:40:45.0 |
HIP 58594 |
10.96 |
| 2026-04-07 00:00 |
12:01:25.99 |
+13:41:50.6 |
HIP 58594 |
7.92 |
| 2026-04-07 12:00 |
12:01:11.62 |
+13:42:54.8 |
HIP 58594 |
5.69 |
| 2026-04-08 00:00 |
12:00:57.33 |
+13:43:57.8 |
HIP 58594 |
5.33 |
| 2026-04-08 12:00 |
12:00:43.12 |
+13:44:59.4 |
HIP 58594 |
7.10 |
| 2026-04-09 00:00 |
12:00:28.99 |
+13:45:59.7 |
HIP 58594 |
9.88 |
| 2026-04-09 12:00 |
12:00:14.94 |
+13:46:58.7 |
HIP 58594 |
13.03 |
| 2026-04-10 00:00 |
12:00:00.98 |
+13:47:56.4 |
HIP 58594 |
16.31 |
| 2026-04-10 12:00 |
11:59:47.10 |
+13:48:52.7 |
HIP 58594 |
19.65 |
| 2026-04-11 00:00 |
11:59:33.32 |
+13:49:47.6 |
HIP 58594 |
23.00 |
| 2026-04-11 12:00 |
11:59:19.62 |
+13:50:41.2 |
HIP 58359 |
22.31 |
| 2026-04-12 00:00 |
11:59:06.03 |
+13:51:33.5 |
HIP 58359 |
19.06 |
| 2026-04-12 12:00 |
11:58:52.52 |
+13:52:24.3 |
HIP 58359 |
15.91 |
| 2026-04-13 00:00 |
11:58:39.12 |
+13:53:13.8 |
HIP 58359 |
12.92 |
| 2026-04-13 12:00 |
11:58:25.82 |
+13:54:01.9 |
HIP 58359 |
10.19 |
| 2026-04-14 00:00 |
11:58:12.62 |
+13:54:48.6 |
HIP 58359 |
7.97 |
| 2026-04-14 12:00 |
11:57:59.52 |
+13:55:33.9 |
HIP 58359 |
6.71 |
| 2026-04-15 00:00 |
11:57:46.54 |
+13:56:17.8 |
HIP 58359 |
6.93 |
| 2026-04-15 12:00 |
11:57:33.66 |
+13:57:00.3 |
HIP 58359 |
8.47 |
| 2026-04-16 00:00 |
11:57:20.90 |
+13:57:41.3 |
HIP 58359 |
10.76 |