285P/LINEAR
Metadata
| Parameter | Value |
|---|---|
| Designation | 285P/LINEAR |
| Type | P |
| Perihelion (tp_cal, UTC) | 2023-01-12T20:28:47.072640Z |
| Orbit solution date (soln_date, UTC) | 2024-06-06T23:12:48Z |
| Obs used | 933 |
| NEO | - |
| M1 | 13.600 |
| K1 | 4.500 |
| PC | - |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2020-02-29.0000000 |
| e | 0.61787770 |
| q (au) | 1.723017 |
| a (au) | 4.509072 |
| i (deg) | 25.023386 |
| Ω (om, deg) | 185.483345 |
| ω (w, deg) | 178.401291 |
| M (ma, deg) | 252.033734 |
Magnitude
Scatter + Global Linear
$$ M_a = (15.549 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 15.549 |
| n | 2.000 |
| gf | 1.000 |
| gb | -1.000 |
| 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 |
|---|---|---|---|
| 2022-06-28 | 2022-08-13 | +85.0046 | -30.978 |
| 2022-08-13 | 2023-01-09 | -1.4071 | +0.571 |
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 | 10:34:26.40 | +00:00:39.6 | HIP 51791 | 22.47 |
| 2026-05-12 12:00 | 10:34:26.34 | +00:01:48.7 | HIP 51791 | 23.57 |
| 2026-05-13 00:00 | 10:34:26.42 | +00:02:57.0 | HIP 51791 | 24.65 |
| 2026-05-13 12:00 | 10:34:26.64 | +00:04:04.3 | HIP 51791 | 25.70 |
| 2026-05-14 00:00 | 10:34:26.99 | +00:05:10.7 | HIP 51791 | 26.74 |
| 2026-05-14 12:00 | 10:34:27.49 | +00:06:16.1 | HIP 51791 | 27.76 |
| 2026-05-15 00:00 | 10:34:28.12 | +00:07:20.7 | HIP 51791 | 28.76 |
| 2026-05-15 12:00 | 10:34:28.90 | +00:08:24.3 | HIP 51791 | 29.75 |
| 2026-05-16 00:00 | 10:34:29.81 | +00:09:27.1 | HIP 51791 | 30.72 |
| 2026-05-16 12:00 | 10:34:30.85 | +00:10:28.9 | HIP 51791 | 31.67 |
| 2026-05-17 00:00 | 10:34:32.04 | +00:11:29.8 | HIP 51791 | 32.61 |
| 2026-05-17 12:00 | 10:34:33.36 | +00:12:29.7 | HIP 51791 | 33.54 |
| 2026-05-18 00:00 | 10:34:34.82 | +00:13:28.7 | HIP 51791 | 34.45 |
| 2026-05-18 12:00 | 10:34:36.41 | +00:14:26.8 | HIP 51791 | 35.35 |
| 2026-05-19 00:00 | 10:34:38.14 | +00:15:24.0 | HIP 51895 | 34.37 |
| 2026-05-19 12:00 | 10:34:40.00 | +00:16:20.2 | HIP 51895 | 33.36 |
| 2026-05-20 00:00 | 10:34:42.00 | +00:17:15.6 | HIP 51895 | 32.35 |
| 2026-05-20 12:00 | 10:34:44.14 | +00:18:09.9 | HIP 51895 | 31.32 |
| 2026-05-21 00:00 | 10:34:46.40 | +00:19:03.4 | HIP 51895 | 30.28 |
| 2026-05-21 12:00 | 10:34:48.80 | +00:19:55.9 | HIP 51895 | 29.23 |
| 2026-05-22 00:00 | 10:34:51.34 | +00:20:47.5 | HIP 51895 | 28.17 |
| 2026-05-22 12:00 | 10:34:54.00 | +00:21:38.2 | HIP 51895 | 27.10 |
| 2026-05-23 00:00 | 10:34:56.80 | +00:22:27.9 | HIP 51895 | 26.02 |
| 2026-05-23 12:00 | 10:34:59.73 | +00:23:16.8 | HIP 51895 | 24.92 |
| 2026-05-24 00:00 | 10:35:02.79 | +00:24:04.7 | HIP 51895 | 23.82 |
| 2026-05-24 12:00 | 10:35:05.98 | +00:24:51.6 | HIP 51895 | 22.70 |
| 2026-05-25 00:00 | 10:35:09.30 | +00:25:37.7 | HIP 51895 | 21.57 |
| 2026-05-25 12:00 | 10:35:12.74 | +00:26:22.8 | HIP 51895 | 20.43 |
| 2026-05-26 00:00 | 10:35:16.32 | +00:27:07.0 | HIP 51895 | 19.28 |
| 2026-05-26 12:00 | 10:35:20.02 | +00:27:50.3 | HIP 51895 | 18.12 |
| 2026-05-27 00:00 | 10:35:23.85 | +00:28:32.7 | HIP 51895 | 16.96 |
| 2026-05-27 12:00 | 10:35:27.81 | +00:29:14.1 | HIP 51895 | 15.79 |
| 2026-05-28 00:00 | 10:35:31.90 | +00:29:54.6 | HIP 51895 | 14.61 |
| 2026-05-28 12:00 | 10:35:36.10 | +00:30:34.3 | HIP 51895 | 13.44 |
| 2026-05-29 00:00 | 10:35:40.44 | +00:31:13.0 | HIP 51895 | 12.27 |
| 2026-05-29 12:00 | 10:35:44.90 | +00:31:50.8 | HIP 51895 | 11.12 |
| 2026-05-30 00:00 | 10:35:49.48 | +00:32:27.7 | HIP 51895 | 10.00 |
| 2026-05-30 12:00 | 10:35:54.19 | +00:33:03.7 | HIP 51895 | 8.92 |
| 2026-05-31 00:00 | 10:35:59.01 | +00:33:38.7 | HIP 51895 | 7.93 |
| 2026-05-31 12:00 | 10:36:03.97 | +00:34:12.9 | HIP 51895 | 7.07 |
| 2026-06-01 00:00 | 10:36:09.04 | +00:34:46.2 | HIP 51895 | 6.39 |
| 2026-06-01 12:00 | 10:36:14.23 | +00:35:18.5 | HIP 51895 | 5.98 |
| 2026-06-02 00:00 | 10:36:19.54 | +00:35:50.0 | HIP 51895 | 5.92 |