C/2024 R4 (PANSTARRS)
Metadata
| Parameter | Value |
|---|---|
| Designation | C/2024 R4 (PANSTARRS) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2027-10-26T15:42:57.769920Z |
| Orbit solution date (soln_date, UTC) | 2026-01-13T08:12:18Z |
| Obs used | 929 |
| NEO | - |
| M1 | 6.300 |
| K1 | 7.750 |
| PC | 0.030 |
| Discovery observation (MPC, UTC) | 2024-09-11T08:54:09.475200Z |
| Discovery magnitude (MPC) | 21.20 w |
| Discovery observatory (MPC) | F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2025-08-17.0000000 |
| e | 1.00259406 |
| q (au) | 4.409013 |
| a (au) | -1699.659354 |
| i (deg) | 95.365480 |
| Ω (om, deg) | 345.936465 |
| ω (w, deg) | 108.995035 |
| M (ma, deg) | -0.011262 |
Magnitude
Scatter + Global Linear
$$ M_a = (1.648 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 1.648 |
| n | 6.000 |
| gf | 1.000 |
| gb | -0.599 |
| 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 |
|---|---|---|---|
| 2024-07-03 | 2025-04-28 | +25.8839 | -23.671 |
| 2025-04-28 | 2026-01-21 | +1.3982 | -1.235 |
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) |
|---|---|---|---|---|
| 2026-02-03 00:00 | 21:44:36.14 | +22:32:17.6 | HIP 107297 | 18.80 |
| 2026-02-03 12:00 | 21:44:48.18 | +22:34:19.4 | HIP 107297 | 18.61 |
| 2026-02-04 00:00 | 21:45:00.25 | +22:36:22.5 | HIP 107394 | 17.52 |
| 2026-02-04 12:00 | 21:45:12.34 | +22:38:26.9 | HIP 107394 | 15.35 |
| 2026-02-05 00:00 | 21:45:24.47 | +22:40:32.5 | HIP 107394 | 13.70 |
| 2026-02-05 12:00 | 21:45:36.62 | +22:42:39.4 | HIP 107394 | 12.80 |
| 2026-02-06 00:00 | 21:45:48.80 | +22:44:47.6 | HIP 107472 | 12.66 |
| 2026-02-06 12:00 | 21:46:01.01 | +22:46:57.0 | HIP 107472 | 10.01 |
| 2026-02-07 00:00 | 21:46:13.24 | +22:49:07.7 | HIP 107498 | 7.88 |
| 2026-02-07 12:00 | 21:46:25.50 | +22:51:19.7 | HIP 107498 | 5.53 |
| 2026-02-08 00:00 | 21:46:37.78 | +22:53:32.9 | HIP 107498 | 4.95 |
| 2026-02-08 12:00 | 21:46:50.08 | +22:55:47.5 | HIP 107498 | 6.66 |
| 2026-02-09 00:00 | 21:47:02.41 | +22:58:03.3 | HIP 107498 | 9.51 |
| 2026-02-09 12:00 | 21:47:14.76 | +23:00:20.3 | HIP 107498 | 12.77 |
| 2026-02-10 00:00 | 21:47:27.13 | +23:02:38.6 | HIP 107498 | 16.21 |
| 2026-02-10 12:00 | 21:47:39.51 | +23:04:58.2 | HIP 107498 | 19.74 |
| 2026-02-11 00:00 | 21:47:51.92 | +23:07:19.1 | HIP 107498 | 23.33 |
| 2026-02-11 12:00 | 21:48:04.34 | +23:09:41.2 | HIP 107498 | 26.96 |
| 2026-02-12 00:00 | 21:48:16.79 | +23:12:04.6 | HIP 107498 | 30.62 |
| 2026-02-12 12:00 | 21:48:29.24 | +23:14:29.2 | HIP 107550 | 33.35 |
| 2026-02-13 00:00 | 21:48:41.72 | +23:16:55.1 | HIP 107550 | 33.43 |
| 2026-02-13 12:00 | 21:48:54.21 | +23:19:22.3 | HIP 107550 | 33.92 |
| 2026-02-14 00:00 | 21:49:06.71 | +23:21:50.7 | HIP 107550 | 34.80 |
| 2026-02-14 12:00 | 21:49:19.22 | +23:24:20.4 | HIP 107550 | 36.04 |
| 2026-02-15 00:00 | 21:49:31.74 | +23:26:51.4 | HIP 107550 | 37.63 |
| 2026-02-15 12:00 | 21:49:44.28 | +23:29:23.6 | HIP 107751 | 35.96 |
| 2026-02-16 00:00 | 21:49:56.83 | +23:31:57.0 | HIP 107751 | 33.55 |
| 2026-02-16 12:00 | 21:50:09.38 | +23:34:31.8 | HIP 107751 | 31.42 |
| 2026-02-17 00:00 | 21:50:21.94 | +23:37:07.7 | HIP 107751 | 29.61 |
| 2026-02-17 12:00 | 21:50:34.51 | +23:39:44.9 | HIP 107751 | 28.20 |
| 2026-02-18 00:00 | 21:50:47.08 | +23:42:23.4 | HIP 107751 | 27.27 |
| 2026-02-18 12:00 | 21:50:59.66 | +23:45:03.1 | HIP 107960 | 24.27 |
| 2026-02-19 00:00 | 21:51:12.25 | +23:47:44.1 | HIP 107960 | 20.34 |
| 2026-02-19 12:00 | 21:51:24.83 | +23:50:26.3 | HIP 107960 | 16.40 |
| 2026-02-20 00:00 | 21:51:37.42 | +23:53:09.7 | HIP 107960 | 12.46 |
| 2026-02-20 12:00 | 21:51:50.01 | +23:55:54.4 | HIP 107960 | 8.51 |
| 2026-02-21 00:00 | 21:52:02.60 | +23:58:40.3 | HIP 107960 | 4.62 |
| 2026-02-21 12:00 | 21:52:15.19 | +24:01:27.5 | HIP 107960 | 1.45 |
| 2026-02-22 00:00 | 21:52:27.78 | +24:04:15.8 | HIP 107960 | 3.88 |
| 2026-02-22 12:00 | 21:52:40.36 | +24:07:05.4 | HIP 107960 | 7.78 |
| 2026-02-23 00:00 | 21:52:52.94 | +24:09:56.2 | HIP 107960 | 11.78 |
| 2026-02-23 12:00 | 21:53:05.52 | +24:12:48.3 | HIP 107960 | 15.82 |
| 2026-02-24 00:00 | 21:53:18.09 | +24:15:41.5 | HIP 107960 | 19.87 |