493P/LONEOS
Metadata
| Parameter | Value |
|---|---|
| Designation | 493P/LONEOS |
| Type | P |
| Perihelion (tp_cal, UTC) | 2026-01-26T13:27:56.888640Z |
| Orbit solution date (soln_date, UTC) | 2026-01-13T08:12:54Z |
| Obs used | 1155 |
| NEO | - |
| M1 | 7.300 |
| K1 | 13.250 |
| PC | 0.030 |
| Discovery observation (MPC, UTC) | 2024-08-30T03:13:46.848000Z |
| Discovery magnitude (MPC) | 19.60 V |
| Discovery observatory (MPC) | 950 · La Palma |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2016-09-29.0000000 |
| e | 0.46361765 |
| q (au) | 3.814350 |
| a (au) | 7.111252 |
| i (deg) | 24.052975 |
| Ω (om, deg) | 1.392453 |
| ω (w, deg) | 83.605193 |
| M (ma, deg) | 182.947873 |
Magnitude
Scatter + Global Linear
$$ M_a = (5.947 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 5.947 |
| n | 6.000 |
| gf | 0.800 |
| gb | -0.500 |
| k | 0.995 |
| δ90 | 1.001 |
| 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 |
|---|---|---|---|
| 2024-08-02 | 2026-01-25 | +7.8182 | -4.946 |
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 | 04:24:12.14 | +50:14:30.3 | HIP 20370 | 26.57 |
| 2026-02-03 12:00 | 04:24:21.24 | +50:11:46.7 | HIP 20370 | 26.78 |
| 2026-02-04 00:00 | 04:24:30.73 | +50:09:03.2 | HIP 20370 | 27.40 |
| 2026-02-04 12:00 | 04:24:40.60 | +50:06:19.9 | HIP 20370 | 28.42 |
| 2026-02-05 00:00 | 04:24:50.86 | +50:03:37.0 | HIP 20370 | 29.80 |
| 2026-02-05 12:00 | 04:25:01.50 | +50:00:54.3 | HIP 20370 | 31.51 |
| 2026-02-06 00:00 | 04:25:12.52 | +49:58:11.8 | HIP 20370 | 33.50 |
| 2026-02-06 12:00 | 04:25:23.93 | +49:55:29.7 | HIP 20370 | 35.74 |
| 2026-02-07 00:00 | 04:25:35.71 | +49:52:47.9 | HIP 20833 | 34.19 |
| 2026-02-07 12:00 | 04:25:47.86 | +49:50:06.5 | HIP 20833 | 30.88 |
| 2026-02-08 00:00 | 04:26:00.39 | +49:47:25.3 | HIP 20833 | 27.53 |
| 2026-02-08 12:00 | 04:26:13.29 | +49:44:44.6 | HIP 20833 | 24.14 |
| 2026-02-09 00:00 | 04:26:26.56 | +49:42:04.2 | HIP 20833 | 20.72 |
| 2026-02-09 12:00 | 04:26:40.20 | +49:39:24.2 | HIP 20833 | 17.26 |
| 2026-02-10 00:00 | 04:26:54.21 | +49:36:44.5 | HIP 20833 | 13.77 |
| 2026-02-10 12:00 | 04:27:08.58 | +49:34:05.3 | HIP 20833 | 10.24 |
| 2026-02-11 00:00 | 04:27:23.31 | +49:31:26.5 | HIP 20833 | 6.68 |
| 2026-02-11 12:00 | 04:27:38.41 | +49:28:48.2 | HIP 20833 | 3.08 |
| 2026-02-12 00:00 | 04:27:53.86 | +49:26:10.3 | HIP 20833 | 0.61 |
| 2026-02-12 12:00 | 04:28:09.67 | +49:23:32.8 | HIP 20833 | 4.24 |
| 2026-02-13 00:00 | 04:28:25.84 | +49:20:55.8 | HIP 20872 | 7.05 |
| 2026-02-13 12:00 | 04:28:42.36 | +49:18:19.3 | HIP 20872 | 5.44 |
| 2026-02-14 00:00 | 04:28:59.23 | +49:15:43.3 | HIP 20872 | 6.20 |
| 2026-02-14 12:00 | 04:29:16.45 | +49:13:07.8 | HIP 20872 | 8.77 |
| 2026-02-15 00:00 | 04:29:34.02 | +49:10:32.7 | HIP 20872 | 12.08 |
| 2026-02-15 12:00 | 04:29:51.93 | +49:07:58.2 | HIP 20872 | 15.70 |
| 2026-02-16 00:00 | 04:30:10.18 | +49:05:24.2 | HIP 20872 | 19.48 |
| 2026-02-16 12:00 | 04:30:28.78 | +49:02:50.7 | HIP 20872 | 23.36 |
| 2026-02-17 00:00 | 04:30:47.71 | +49:00:17.8 | HIP 20872 | 27.32 |
| 2026-02-17 12:00 | 04:31:06.98 | +48:57:45.4 | HIP 20872 | 31.33 |
| 2026-02-18 00:00 | 04:31:26.59 | +48:55:13.5 | HIP 20872 | 35.40 |
| 2026-02-18 12:00 | 04:31:46.52 | +48:52:42.2 | HIP 21166 | 36.10 |
| 2026-02-19 00:00 | 04:32:06.79 | +48:50:11.5 | HIP 21166 | 33.28 |
| 2026-02-19 12:00 | 04:32:27.39 | +48:47:41.3 | HIP 21166 | 30.78 |
| 2026-02-20 00:00 | 04:32:48.31 | +48:45:11.8 | HIP 21166 | 28.71 |
| 2026-02-20 12:00 | 04:33:09.55 | +48:42:42.7 | HIP 21166 | 27.18 |
| 2026-02-21 00:00 | 04:33:31.11 | +48:40:14.3 | HIP 21166 | 26.32 |
| 2026-02-21 12:00 | 04:33:53.00 | +48:37:46.5 | HIP 21166 | 26.20 |
| 2026-02-22 00:00 | 04:34:15.19 | +48:35:19.2 | HIP 21166 | 26.85 |
| 2026-02-22 12:00 | 04:34:37.71 | +48:32:52.6 | HIP 21507 | 26.48 |
| 2026-02-23 00:00 | 04:35:00.53 | +48:30:26.5 | HIP 21507 | 22.13 |
| 2026-02-23 12:00 | 04:35:23.66 | +48:28:01.1 | HIP 21507 | 17.80 |
| 2026-02-24 00:00 | 04:35:47.09 | +48:25:36.2 | HIP 21507 | 13.55 |