C/2020 K1 (PANSTARRS)
Metadata
| Parameter | Value |
|---|---|
| Designation | C/2020 K1 (PANSTARRS) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2023-05-09T01:41:32.504640Z |
| Orbit solution date (soln_date, UTC) | 2026-03-07T11:42:49Z |
| Obs used | 3655 |
| NEO | - |
| M1 | 8.600 |
| K1 | 6.000 |
| PC | - |
| Discovery observation (MPC, UTC) | 2020-05-17T12:17:42.374400Z |
| Discovery magnitude (MPC) | 20.62 w |
| Discovery observatory (MPC) | F52 · Pan-STARRS 2, Haleakala |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2022-07-31.0000000 |
| e | 0.99993441 |
| q (au) | 3.073431 |
| a (au) | 46857.294566 |
| i (deg) | 89.664146 |
| Ω (om, deg) | 94.355504 |
| ω (w, deg) | 213.979196 |
| M (ma, deg) | 359.999973 |
Magnitude
Scatter + Global Linear
$$ M_a = (9.629 + 3.286\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 9.629 |
| n | 3.286 |
| gf | 0.997 |
| gb | -0.751 |
| k | 0.800 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) | End (UTC) | a | b |
|---|---|---|---|
| 2020-04-17 | 2022-05-11 | +3.0096 | -2.438 |
| 2022-05-11 | 2022-08-27 | +3.0169 | -2.088 |
| 2022-08-27 | 2023-05-09 | -4.1442 | +1.851 |
| 2023-05-09 | 2024-01-03 | +2.1871 | -0.968 |
| 2024-01-03 | 2025-03-10 | +0.4091 | -0.340 |
| 2025-03-10 | 2026-01-09 | +12.3405 | -10.351 |
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) |
|---|---|---|---|---|
| 2026-05-12 00:00 | 05:58:22.81 | -09:06:51.4 | HIP 28318 | 16.48 |
| 2026-05-12 12:00 | 05:58:32.24 | -09:05:10.6 | HIP 28318 | 13.83 |
| 2026-05-13 00:00 | 05:58:41.72 | -09:03:30.5 | HIP 28318 | 11.30 |
| 2026-05-13 12:00 | 05:58:51.25 | -09:01:51.1 | HIP 28318 | 8.99 |
| 2026-05-14 00:00 | 05:59:00.82 | -09:00:12.6 | HIP 28318 | 7.12 |
| 2026-05-14 12:00 | 05:59:10.43 | -08:58:34.7 | HIP 28318 | 6.11 |
| 2026-05-15 00:00 | 05:59:20.09 | -08:56:57.7 | HIP 28318 | 6.38 |
| 2026-05-15 12:00 | 05:59:29.79 | -08:55:21.4 | HIP 28318 | 7.81 |
| 2026-05-16 00:00 | 05:59:39.54 | -08:53:45.8 | HIP 28318 | 9.90 |
| 2026-05-16 12:00 | 05:59:49.32 | -08:52:11.0 | HIP 28318 | 12.33 |
| 2026-05-17 00:00 | 05:59:59.14 | -08:50:37.0 | HIP 28318 | 14.93 |
| 2026-05-17 12:00 | 06:00:09.01 | -08:49:03.8 | HIP 28318 | 17.63 |
| 2026-05-18 00:00 | 06:00:18.91 | -08:47:31.3 | HIP 28318 | 20.39 |
| 2026-05-18 12:00 | 06:00:28.85 | -08:45:59.5 | HIP 28318 | 23.18 |
| 2026-05-19 00:00 | 06:00:38.83 | -08:44:28.6 | HIP 28598 | 23.32 |
| 2026-05-19 12:00 | 06:00:48.84 | -08:42:58.4 | HIP 28598 | 20.55 |
| 2026-05-20 00:00 | 06:00:58.89 | -08:41:29.0 | HIP 28598 | 17.81 |
| 2026-05-20 12:00 | 06:01:08.98 | -08:40:00.3 | HIP 28598 | 15.13 |
| 2026-05-21 00:00 | 06:01:19.10 | -08:38:32.4 | HIP 28598 | 12.53 |
| 2026-05-21 12:00 | 06:01:29.26 | -08:37:05.3 | HIP 28598 | 10.09 |
| 2026-05-22 00:00 | 06:01:39.45 | -08:35:38.9 | HIP 28598 | 7.94 |
| 2026-05-22 12:00 | 06:01:49.67 | -08:34:13.3 | HIP 28598 | 6.41 |
| 2026-05-23 00:00 | 06:01:59.92 | -08:32:48.5 | HIP 28598 | 5.98 |
| 2026-05-23 12:00 | 06:02:10.21 | -08:31:24.4 | HIP 28598 | 6.86 |
| 2026-05-24 00:00 | 06:02:20.53 | -08:30:01.1 | HIP 28598 | 8.67 |
| 2026-05-24 12:00 | 06:02:30.87 | -08:28:38.6 | HIP 28598 | 10.95 |
| 2026-05-25 00:00 | 06:02:41.25 | -08:27:16.8 | HIP 28653 | 10.08 |
| 2026-05-25 12:00 | 06:02:51.65 | -08:25:55.8 | HIP 28653 | 7.78 |
| 2026-05-26 00:00 | 06:03:02.08 | -08:24:35.6 | HIP 28653 | 6.05 |
| 2026-05-26 12:00 | 06:03:12.55 | -08:23:16.1 | HIP 28653 | 5.45 |
| 2026-05-27 00:00 | 06:03:23.03 | -08:21:57.4 | HIP 28653 | 6.31 |
| 2026-05-27 12:00 | 06:03:33.55 | -08:20:39.4 | HIP 28653 | 8.18 |
| 2026-05-28 00:00 | 06:03:44.09 | -08:19:22.2 | HIP 28653 | 10.54 |
| 2026-05-28 12:00 | 06:03:54.65 | -08:18:05.8 | HIP 28653 | 13.13 |
| 2026-05-29 00:00 | 06:04:05.24 | -08:16:50.1 | HIP 28653 | 15.84 |
| 2026-05-29 12:00 | 06:04:15.85 | -08:15:35.1 | HIP 28653 | 18.61 |
| 2026-05-30 00:00 | 06:04:26.49 | -08:14:21.0 | HIP 28833 | 16.85 |
| 2026-05-30 12:00 | 06:04:37.15 | -08:13:07.5 | HIP 28833 | 14.29 |
| 2026-05-31 00:00 | 06:04:47.83 | -08:11:54.9 | HIP 28833 | 11.89 |
| 2026-05-31 12:00 | 06:04:58.54 | -08:10:43.0 | HIP 28833 | 9.78 |
| 2026-06-01 00:00 | 06:05:09.26 | -08:09:31.8 | HIP 28833 | 8.19 |
| 2026-06-01 12:00 | 06:05:20.01 | -08:08:21.4 | HIP 28833 | 7.46 |
| 2026-06-02 00:00 | 06:05:30.77 | -08:07:11.8 | HIP 28833 | 7.82 |