P/2023 S1 (PANSTARRS)
Metadata
| Parameter | Value |
|---|---|
| Designation | P/2023 S1 (PANSTARRS) |
| Type | P |
| Perihelion (tp_cal, UTC) | 2025-02-24T01:28:44.201280Z |
| Orbit solution date (soln_date, UTC) | 2026-05-22T14:12:28Z |
| Obs used | 1928 |
| NEO | - |
| M1 | 10.300 |
| K1 | 11.500 |
| PC | 0.030 |
| Discovery observation (MPC, UTC) | 2023-09-20T14:30:23.443200Z |
| Discovery magnitude (MPC) | 20.36 w |
| Discovery observatory (MPC) | F52 · Pan-STARRS 2, Haleakala |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2024-10-31.0000000 |
| e | 0.31884323 |
| q (au) | 2.619726 |
| a (au) | 3.845996 |
| i (deg) | 9.156216 |
| Ω (om, deg) | 317.292570 |
| ω (w, deg) | 180.274180 |
| M (ma, deg) | 344.833705 |
Magnitude
Scatter + Global Linear
$$ M_a = (9.337 + 5.218\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 9.337 |
| n | 5.218 |
| gf | 0.883 |
| gb | -0.801 |
| k | 0.997 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) | End (UTC) | a | b |
|---|---|---|---|
| 2023-09-15 | 2025-02-24 | +2.2459 | -1.234 |
| 2025-02-24 | 2026-02-25 | +16.8467 | -7.135 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Finding Chart
Ephemeris
| Date/Time (UTC) | RA (J2000) | Dec (J2000) | Nearest HIP | Dist from HIP (arcmin) |
|---|---|---|---|---|
| 2026-06-01 00:00 | 14:49:49.22 | -29:15:58.0 | HIP 72547 | 4.82 |
| 2026-06-01 12:00 | 14:49:31.61 | -29:13:45.9 | HIP 72547 | 8.54 |
| 2026-06-02 00:00 | 14:49:14.25 | -29:11:33.6 | HIP 72547 | 12.69 |
| 2026-06-02 12:00 | 14:48:57.12 | -29:09:21.2 | HIP 72551 | 15.09 |
| 2026-06-03 00:00 | 14:48:40.24 | -29:07:08.7 | HIP 72551 | 17.65 |
| 2026-06-03 12:00 | 14:48:23.60 | -29:04:56.1 | HIP 72551 | 20.75 |
| 2026-06-04 00:00 | 14:48:07.22 | -29:02:43.4 | HIP 72294 | 21.84 |
| 2026-06-04 12:00 | 14:47:51.08 | -29:00:30.8 | HIP 72294 | 17.92 |
| 2026-06-05 00:00 | 14:47:35.20 | -28:58:18.1 | HIP 72294 | 14.17 |
| 2026-06-05 12:00 | 14:47:19.57 | -28:56:05.5 | HIP 72294 | 10.71 |
| 2026-06-06 00:00 | 14:47:04.20 | -28:53:53.0 | HIP 72294 | 7.87 |
| 2026-06-06 12:00 | 14:46:49.10 | -28:51:40.6 | HIP 72294 | 6.41 |
| 2026-06-07 00:00 | 14:46:34.25 | -28:49:28.3 | HIP 72294 | 7.17 |
| 2026-06-07 12:00 | 14:46:19.67 | -28:47:16.2 | HIP 72294 | 9.56 |
| 2026-06-08 00:00 | 14:46:05.36 | -28:45:04.3 | HIP 72294 | 12.65 |
| 2026-06-08 12:00 | 14:45:51.32 | -28:42:52.6 | HIP 72294 | 16.01 |
| 2026-06-09 00:00 | 14:45:37.55 | -28:40:41.1 | HIP 72294 | 19.47 |
| 2026-06-09 12:00 | 14:45:24.05 | -28:38:29.9 | HIP 72027 | 19.89 |
| 2026-06-10 00:00 | 14:45:10.82 | -28:36:19.0 | HIP 72027 | 16.36 |
| 2026-06-10 12:00 | 14:44:57.87 | -28:34:08.5 | HIP 72027 | 12.93 |
| 2026-06-11 00:00 | 14:44:45.20 | -28:31:58.3 | HIP 72027 | 9.68 |
| 2026-06-11 12:00 | 14:44:32.82 | -28:29:48.5 | HIP 72027 | 6.77 |
| 2026-06-12 00:00 | 14:44:20.71 | -28:27:39.1 | HIP 72027 | 4.76 |
| 2026-06-12 12:00 | 14:44:08.89 | -28:25:30.1 | HIP 72035 | 4.34 |
| 2026-06-13 00:00 | 14:43:57.35 | -28:23:21.6 | HIP 72035 | 3.17 |
| 2026-06-13 12:00 | 14:43:46.10 | -28:21:13.7 | HIP 72035 | 4.76 |
| 2026-06-14 00:00 | 14:43:35.13 | -28:19:06.2 | HIP 72035 | 7.47 |
| 2026-06-14 12:00 | 14:43:24.46 | -28:16:59.3 | HIP 72035 | 10.40 |
| 2026-06-15 00:00 | 14:43:14.08 | -28:14:52.9 | HIP 72035 | 13.38 |
| 2026-06-15 12:00 | 14:43:03.99 | -28:12:47.2 | HIP 72035 | 16.35 |
| 2026-06-16 00:00 | 14:42:54.19 | -28:10:42.1 | HIP 71862 | 14.27 |
| 2026-06-16 12:00 | 14:42:44.69 | -28:08:37.6 | HIP 71862 | 11.48 |
| 2026-06-17 00:00 | 14:42:35.48 | -28:06:33.8 | HIP 71862 | 8.85 |
| 2026-06-17 12:00 | 14:42:26.57 | -28:04:30.7 | HIP 71862 | 6.51 |
| 2026-06-18 00:00 | 14:42:17.96 | -28:02:28.3 | HIP 71862 | 4.82 |
| 2026-06-18 12:00 | 14:42:09.64 | -28:00:26.6 | HIP 71862 | 4.45 |
| 2026-06-19 00:00 | 14:42:01.62 | -27:58:25.7 | HIP 71862 | 5.60 |
| 2026-06-19 12:00 | 14:41:53.90 | -27:56:25.6 | HIP 71862 | 7.55 |
| 2026-06-20 00:00 | 14:41:46.48 | -27:54:26.3 | HIP 71862 | 9.80 |
| 2026-06-20 12:00 | 14:41:39.35 | -27:52:27.8 | HIP 71862 | 12.14 |
| 2026-06-21 00:00 | 14:41:32.53 | -27:50:30.1 | HIP 71862 | 14.50 |
| 2026-06-21 12:00 | 14:41:26.00 | -27:48:33.3 | HIP 71862 | 16.86 |
| 2026-06-22 00:00 | 14:41:19.77 | -27:46:37.3 | HIP 71862 | 19.19 |