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) |
|---|---|---|---|---|
| 2026-03-26 00:00 | 21:11:02.70 | -40:08:17.4 | HIP 104555 | 10.37 |
| 2026-03-26 12:00 | 21:11:32.82 | -40:09:01.1 | HIP 104680 | 10.55 |
| 2026-03-27 00:00 | 21:12:02.86 | -40:09:45.8 | HIP 104680 | 6.69 |
| 2026-03-27 12:00 | 21:12:32.82 | -40:10:31.5 | HIP 104680 | 6.69 |
| 2026-03-28 00:00 | 21:13:02.71 | -40:11:18.0 | HIP 104680 | 10.53 |
| 2026-03-28 12:00 | 21:13:32.52 | -40:12:05.6 | HIP 104680 | 15.58 |
| 2026-03-29 00:00 | 21:14:02.25 | -40:12:54.1 | HIP 104824 | 15.24 |
| 2026-03-29 12:00 | 21:14:31.90 | -40:13:43.5 | HIP 104824 | 16.49 |
| 2026-03-30 00:00 | 21:15:01.47 | -40:14:34.0 | HIP 104925 | 15.99 |
| 2026-03-30 12:00 | 21:15:30.96 | -40:15:25.4 | HIP 105023 | 10.78 |
| 2026-03-31 00:00 | 21:16:00.37 | -40:16:17.8 | HIP 105023 | 5.59 |
| 2026-03-31 12:00 | 21:16:29.70 | -40:17:11.2 | HIP 105023 | 3.23 |
| 2026-04-01 00:00 | 21:16:58.94 | -40:18:05.6 | HIP 105023 | 7.31 |
| 2026-04-01 12:00 | 21:17:28.10 | -40:19:01.0 | HIP 105023 | 12.64 |
| 2026-04-02 00:00 | 21:17:57.18 | -40:19:57.5 | HIP 105023 | 18.14 |
| 2026-04-02 12:00 | 21:18:26.17 | -40:20:54.9 | HIP 105354 | 23.11 |
| 2026-04-03 00:00 | 21:18:55.08 | -40:21:53.4 | HIP 105354 | 17.58 |
| 2026-04-03 12:00 | 21:19:23.90 | -40:22:53.0 | HIP 105354 | 12.12 |
| 2026-04-04 00:00 | 21:19:52.63 | -40:23:53.5 | HIP 105354 | 6.87 |
| 2026-04-04 12:00 | 21:20:21.28 | -40:24:55.2 | HIP 105354 | 3.01 |
| 2026-04-05 00:00 | 21:20:49.84 | -40:25:57.9 | HIP 105354 | 5.68 |
| 2026-04-05 12:00 | 21:21:18.30 | -40:27:01.7 | HIP 105354 | 10.78 |
| 2026-04-06 00:00 | 21:21:46.68 | -40:28:06.5 | HIP 105354 | 16.14 |
| 2026-04-06 12:00 | 21:22:14.96 | -40:29:12.4 | HIP 105619 | 20.21 |
| 2026-04-07 00:00 | 21:22:43.16 | -40:30:19.5 | HIP 105638 | 17.13 |
| 2026-04-07 12:00 | 21:23:11.25 | -40:31:27.6 | HIP 105638 | 12.79 |
| 2026-04-08 00:00 | 21:23:39.26 | -40:32:36.8 | HIP 105638 | 9.64 |
| 2026-04-08 12:00 | 21:24:07.17 | -40:33:47.2 | HIP 105638 | 9.00 |
| 2026-04-09 00:00 | 21:24:34.98 | -40:34:58.7 | HIP 105638 | 11.29 |
| 2026-04-09 12:00 | 21:25:02.70 | -40:36:11.3 | HIP 105638 | 15.21 |
| 2026-04-10 00:00 | 21:25:30.32 | -40:37:25.0 | HIP 105638 | 19.82 |
| 2026-04-10 12:00 | 21:25:57.84 | -40:38:39.9 | HIP 105638 | 24.71 |
| 2026-04-11 00:00 | 21:26:25.26 | -40:39:56.0 | HIP 106045 | 26.78 |
| 2026-04-11 12:00 | 21:26:52.58 | -40:41:13.2 | HIP 106045 | 21.54 |
| 2026-04-12 00:00 | 21:27:19.80 | -40:42:31.6 | HIP 106045 | 16.37 |
| 2026-04-12 12:00 | 21:27:46.91 | -40:43:51.2 | HIP 106045 | 11.37 |
| 2026-04-13 00:00 | 21:28:13.92 | -40:45:11.9 | HIP 106045 | 6.88 |
| 2026-04-13 12:00 | 21:28:40.83 | -40:46:33.9 | HIP 106045 | 4.66 |
| 2026-04-14 00:00 | 21:29:07.62 | -40:47:57.0 | HIP 106045 | 7.20 |
| 2026-04-14 12:00 | 21:29:34.32 | -40:49:21.4 | HIP 106045 | 11.71 |
| 2026-04-15 00:00 | 21:30:00.90 | -40:50:47.0 | HIP 106045 | 16.65 |
| 2026-04-15 12:00 | 21:30:27.37 | -40:52:13.8 | HIP 106045 | 21.72 |
| 2026-04-16 00:00 | 21:30:53.73 | -40:53:41.8 | HIP 106327 | 21.82 |