P/2011 N1 (ASH)
Metadata
| Parameter | Value |
|---|---|
| Designation | P/2011 N1 (ASH) |
| Type | P |
| Perihelion (tp_cal, UTC) | 2012-05-31T06:52:34.999680Z |
| Orbit solution date (soln_date, UTC) | 2021-04-15T23:31:52Z |
| Obs used | 269 |
| NEO | - |
| M1 | 12.800 |
| K1 | 5.250 |
| PC | - |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2011-12-30.0000000 |
| e | 0.54594610 |
| q (au) | 2.857717 |
| a (au) | 6.293785 |
| i (deg) | 35.668884 |
| Ω (om, deg) | 77.690510 |
| ω (w, deg) | 331.056188 |
| M (ma, deg) | 350.431581 |
Magnitude
Scatter + Global Linear
$$ M_a = (12.378 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 12.378 |
| n | 2.000 |
| gf | 0.999 |
| gb | -0.562 |
| k | 1.000 |
| 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 |
|---|---|---|---|
| 2011-07-01 | 2012-02-01 | +4.8034 | -2.824 |
| 2012-09-29 | 2014-03-21 | -1.2040 | +2.406 |
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 | 20:15:27.78 | -39:55:37.6 | HIP 99851 | 6.31 |
| 2026-02-03 12:00 | 20:16:01.78 | -39:55:20.0 | HIP 99851 | 9.03 |
| 2026-02-04 00:00 | 20:16:35.77 | -39:55:02.7 | HIP 99851 | 14.43 |
| 2026-02-04 12:00 | 20:17:09.77 | -39:54:45.8 | HIP 99939 | 17.75 |
| 2026-02-05 00:00 | 20:17:43.76 | -39:54:29.2 | HIP 100045 | 16.64 |
| 2026-02-05 12:00 | 20:18:17.74 | -39:54:12.9 | HIP 100238 | 17.57 |
| 2026-02-06 00:00 | 20:18:51.72 | -39:53:57.0 | HIP 100238 | 11.28 |
| 2026-02-06 12:00 | 20:19:25.70 | -39:53:41.3 | HIP 100238 | 5.53 |
| 2026-02-07 00:00 | 20:19:59.67 | -39:53:26.1 | HIP 100238 | 4.37 |
| 2026-02-07 12:00 | 20:20:33.63 | -39:53:11.1 | HIP 100293 | 4.29 |
| 2026-02-08 00:00 | 20:21:07.59 | -39:52:56.6 | HIP 100293 | 8.42 |
| 2026-02-08 12:00 | 20:21:41.53 | -39:52:42.3 | HIP 100293 | 14.43 |
| 2026-02-09 00:00 | 20:22:15.47 | -39:52:28.5 | HIP 100293 | 20.74 |
| 2026-02-09 12:00 | 20:22:49.40 | -39:52:15.0 | HIP 100625 | 18.12 |
| 2026-02-10 00:00 | 20:23:23.32 | -39:52:01.9 | HIP 100625 | 12.40 |
| 2026-02-10 12:00 | 20:23:57.23 | -39:51:49.1 | HIP 100625 | 8.00 |
| 2026-02-11 00:00 | 20:24:31.12 | -39:51:36.8 | HIP 100625 | 7.70 |
| 2026-02-11 12:00 | 20:25:05.01 | -39:51:24.8 | HIP 100625 | 11.81 |
| 2026-02-12 00:00 | 20:25:38.88 | -39:51:13.2 | HIP 100625 | 17.45 |
| 2026-02-12 12:00 | 20:26:12.73 | -39:51:02.1 | HIP 100626 | 23.53 |
| 2026-02-13 00:00 | 20:26:46.58 | -39:50:51.3 | HIP 100904 | 20.98 |
| 2026-02-13 12:00 | 20:27:20.40 | -39:50:40.9 | HIP 100904 | 18.92 |
| 2026-02-14 00:00 | 20:27:54.21 | -39:50:31.0 | HIP 100904 | 19.01 |
| 2026-02-14 12:00 | 20:28:28.00 | -39:50:21.4 | HIP 100904 | 21.19 |
| 2026-02-15 00:00 | 20:29:01.78 | -39:50:12.3 | HIP 100904 | 24.94 |
| 2026-02-15 12:00 | 20:29:35.54 | -39:50:03.7 | HIP 101145 | 22.94 |
| 2026-02-16 00:00 | 20:30:09.27 | -39:49:55.5 | HIP 101145 | 21.91 |
| 2026-02-16 12:00 | 20:30:42.99 | -39:49:47.7 | HIP 101145 | 22.77 |
| 2026-02-17 00:00 | 20:31:16.68 | -39:49:40.3 | HIP 101145 | 25.32 |
| 2026-02-17 12:00 | 20:31:50.36 | -39:49:33.5 | HIP 101466 | 26.01 |
| 2026-02-18 00:00 | 20:32:24.01 | -39:49:27.0 | HIP 101466 | 20.62 |
| 2026-02-18 12:00 | 20:32:57.64 | -39:49:21.1 | HIP 101466 | 16.07 |
| 2026-02-19 00:00 | 20:33:31.24 | -39:49:15.6 | HIP 101466 | 13.23 |
| 2026-02-19 12:00 | 20:34:04.82 | -39:49:10.6 | HIP 101466 | 13.25 |
| 2026-02-20 00:00 | 20:34:38.37 | -39:49:06.1 | HIP 101625 | 15.81 |
| 2026-02-20 12:00 | 20:35:11.90 | -39:49:02.1 | HIP 101625 | 10.72 |
| 2026-02-21 00:00 | 20:35:45.39 | -39:48:58.6 | HIP 101625 | 7.94 |
| 2026-02-21 12:00 | 20:36:18.86 | -39:48:55.6 | HIP 101625 | 9.71 |
| 2026-02-22 00:00 | 20:36:52.30 | -39:48:53.0 | HIP 101625 | 14.43 |
| 2026-02-22 12:00 | 20:37:25.72 | -39:48:51.0 | HIP 101625 | 20.12 |
| 2026-02-23 00:00 | 20:37:59.10 | -39:48:49.6 | HIP 101625 | 26.15 |
| 2026-02-23 12:00 | 20:38:32.45 | -39:48:48.6 | HIP 101625 | 32.32 |
| 2026-02-24 00:00 | 20:39:05.76 | -39:48:48.2 | HIP 101990 | 31.37 |