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) |
|---|---|---|---|---|
| 2026-05-12 00:00 | 21:50:46.94 | -42:40:23.4 | HIP 107990 | 23.40 |
| 2026-05-12 12:00 | 21:51:05.95 | -42:43:03.8 | HIP 107990 | 19.11 |
| 2026-05-13 00:00 | 21:51:24.79 | -42:45:45.6 | HIP 107990 | 14.90 |
| 2026-05-13 12:00 | 21:51:43.45 | -42:48:28.8 | HIP 107990 | 10.85 |
| 2026-05-14 00:00 | 21:52:01.94 | -42:51:13.6 | HIP 107990 | 7.24 |
| 2026-05-14 12:00 | 21:52:20.26 | -42:53:59.8 | HIP 107990 | 5.07 |
| 2026-05-15 00:00 | 21:52:38.39 | -42:56:47.5 | HIP 107990 | 6.10 |
| 2026-05-15 12:00 | 21:52:56.35 | -42:59:36.7 | HIP 107942 | 9.13 |
| 2026-05-16 00:00 | 21:53:14.13 | -43:02:27.3 | HIP 107942 | 12.87 |
| 2026-05-16 12:00 | 21:53:31.72 | -43:05:19.4 | HIP 107942 | 16.87 |
| 2026-05-17 00:00 | 21:53:49.13 | -43:08:13.0 | HIP 107942 | 20.97 |
| 2026-05-17 12:00 | 21:54:06.36 | -43:11:08.0 | HIP 107942 | 25.11 |
| 2026-05-18 00:00 | 21:54:23.40 | -43:14:04.5 | HIP 107942 | 29.27 |
| 2026-05-18 12:00 | 21:54:40.25 | -43:17:02.5 | HIP 108134 | 30.46 |
| 2026-05-19 00:00 | 21:54:56.91 | -43:20:01.9 | HIP 108134 | 27.91 |
| 2026-05-19 12:00 | 21:55:13.38 | -43:23:02.8 | HIP 108134 | 25.77 |
| 2026-05-20 00:00 | 21:55:29.66 | -43:26:05.2 | HIP 108134 | 24.15 |
| 2026-05-20 12:00 | 21:55:45.75 | -43:29:09.0 | HIP 108134 | 23.16 |
| 2026-05-21 00:00 | 21:56:01.64 | -43:32:14.2 | HIP 108134 | 22.87 |
| 2026-05-21 12:00 | 21:56:17.34 | -43:35:20.9 | HIP 108134 | 23.31 |
| 2026-05-22 00:00 | 21:56:32.84 | -43:38:29.0 | HIP 108134 | 24.43 |
| 2026-05-22 12:00 | 21:56:48.15 | -43:41:38.5 | HIP 108134 | 26.14 |
| 2026-05-23 00:00 | 21:57:03.25 | -43:44:49.5 | HIP 108484 | 25.12 |
| 2026-05-23 12:00 | 21:57:18.15 | -43:48:01.9 | HIP 108484 | 20.93 |
| 2026-05-24 00:00 | 21:57:32.85 | -43:51:15.7 | HIP 108484 | 16.76 |
| 2026-05-24 12:00 | 21:57:47.35 | -43:54:31.0 | HIP 108484 | 12.59 |
| 2026-05-25 00:00 | 21:58:01.65 | -43:57:47.6 | HIP 108484 | 8.45 |
| 2026-05-25 12:00 | 21:58:15.74 | -44:01:05.7 | HIP 108484 | 4.36 |
| 2026-05-26 00:00 | 21:58:29.62 | -44:04:25.1 | HIP 108484 | 1.17 |
| 2026-05-26 12:00 | 21:58:43.29 | -44:07:46.0 | HIP 108484 | 4.29 |
| 2026-05-27 00:00 | 21:58:56.75 | -44:11:08.2 | HIP 108484 | 8.36 |
| 2026-05-27 12:00 | 21:59:10.01 | -44:14:31.8 | HIP 108484 | 12.48 |
| 2026-05-28 00:00 | 21:59:23.05 | -44:17:56.9 | HIP 108484 | 16.61 |
| 2026-05-28 12:00 | 21:59:35.87 | -44:21:23.2 | HIP 108665 | 15.06 |
| 2026-05-29 00:00 | 21:59:48.48 | -44:24:51.0 | HIP 108665 | 11.75 |
| 2026-05-29 12:00 | 22:00:00.88 | -44:28:20.1 | HIP 108665 | 9.19 |
| 2026-05-30 00:00 | 22:00:13.05 | -44:31:50.6 | HIP 108665 | 8.09 |
| 2026-05-30 12:00 | 22:00:25.01 | -44:35:22.4 | HIP 108665 | 9.03 |
| 2026-05-31 00:00 | 22:00:36.74 | -44:38:55.5 | HIP 108665 | 11.50 |
| 2026-05-31 12:00 | 22:00:48.25 | -44:42:30.0 | HIP 108665 | 14.75 |
| 2026-06-01 00:00 | 22:00:59.54 | -44:46:05.8 | HIP 108665 | 18.38 |
| 2026-06-01 12:00 | 22:01:10.60 | -44:49:43.0 | HIP 108665 | 22.19 |
| 2026-06-02 00:00 | 22:01:21.44 | -44:53:21.4 | HIP 108665 | 26.11 |