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 | -0.500 |
| 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) |
|---|---|---|---|---|
| 2026-07-29 00:00 | 21:52:05.06 | -52:48:18.3 | HIP 107892 | 6.30 |
| 2026-07-29 12:00 | 21:51:44.05 | -52:51:53.1 | HIP 107892 | 8.29 |
| 2026-07-30 00:00 | 21:51:22.82 | -52:55:25.8 | HIP 107892 | 11.95 |
| 2026-07-30 12:00 | 21:51:01.37 | -52:58:56.5 | HIP 107892 | 16.19 |
| 2026-07-31 00:00 | 21:50:39.70 | -53:02:25.1 | HIP 107682 | 17.25 |
| 2026-07-31 12:00 | 21:50:17.82 | -53:05:51.7 | HIP 107682 | 14.70 |
| 2026-08-01 00:00 | 21:49:55.73 | -53:09:16.0 | HIP 107831 | 13.31 |
| 2026-08-01 12:00 | 21:49:33.44 | -53:12:38.3 | HIP 107831 | 13.11 |
| 2026-08-02 00:00 | 21:49:10.94 | -53:15:58.3 | HIP 107831 | 14.58 |
| 2026-08-02 12:00 | 21:48:48.25 | -53:19:16.0 | HIP 107831 | 17.29 |
| 2026-08-03 00:00 | 21:48:25.37 | -53:22:31.5 | HIP 107831 | 20.75 |
| 2026-08-03 12:00 | 21:48:02.30 | -53:25:44.7 | HIP 107831 | 24.64 |
| 2026-08-04 00:00 | 21:47:39.04 | -53:28:55.5 | HIP 107463 | 27.21 |
| 2026-08-04 12:00 | 21:47:15.61 | -53:32:04.0 | HIP 107463 | 28.25 |
| 2026-08-05 00:00 | 21:46:52.00 | -53:35:10.1 | HIP 107460 | 27.42 |
| 2026-08-05 12:00 | 21:46:28.22 | -53:38:13.7 | HIP 107460 | 23.52 |
| 2026-08-06 00:00 | 21:46:04.27 | -53:41:14.9 | HIP 107460 | 20.00 |
| 2026-08-06 12:00 | 21:45:40.17 | -53:44:13.6 | HIP 107460 | 17.07 |
| 2026-08-07 00:00 | 21:45:15.91 | -53:47:09.8 | HIP 107460 | 15.07 |
| 2026-08-07 12:00 | 21:44:51.50 | -53:50:03.4 | HIP 107281 | 12.61 |
| 2026-08-08 00:00 | 21:44:26.94 | -53:52:54.4 | HIP 107281 | 8.03 |
| 2026-08-08 12:00 | 21:44:02.25 | -53:55:42.8 | HIP 107281 | 3.54 |
| 2026-08-09 00:00 | 21:43:37.42 | -53:58:28.6 | HIP 107281 | 1.67 |
| 2026-08-09 12:00 | 21:43:12.46 | -54:01:11.7 | HIP 107281 | 5.91 |
| 2026-08-10 00:00 | 21:42:47.38 | -54:03:52.1 | HIP 107281 | 10.42 |
| 2026-08-10 12:00 | 21:42:22.18 | -54:06:29.8 | HIP 107281 | 14.94 |
| 2026-08-11 00:00 | 21:41:56.88 | -54:09:04.7 | HIP 107281 | 19.45 |
| 2026-08-11 12:00 | 21:41:31.46 | -54:11:36.8 | HIP 107281 | 23.95 |
| 2026-08-12 00:00 | 21:41:05.95 | -54:14:06.1 | HIP 107281 | 28.43 |
| 2026-08-12 12:00 | 21:40:40.35 | -54:16:32.6 | HIP 107289 | 31.33 |
| 2026-08-13 00:00 | 21:40:14.66 | -54:18:56.3 | HIP 106700 | 31.10 |
| 2026-08-13 12:00 | 21:39:48.89 | -54:21:17.1 | HIP 106700 | 27.89 |
| 2026-08-14 00:00 | 21:39:23.05 | -54:23:35.0 | HIP 106700 | 25.03 |
| 2026-08-14 12:00 | 21:38:57.13 | -54:25:50.0 | HIP 106700 | 22.64 |
| 2026-08-15 00:00 | 21:38:31.16 | -54:28:02.0 | HIP 106668 | 19.57 |
| 2026-08-15 12:00 | 21:38:05.14 | -54:30:11.1 | HIP 106668 | 16.25 |
| 2026-08-16 00:00 | 21:37:39.07 | -54:32:17.3 | HIP 106668 | 13.49 |
| 2026-08-16 12:00 | 21:37:12.95 | -54:34:20.4 | HIP 106668 | 11.70 |
| 2026-08-17 00:00 | 21:36:46.80 | -54:36:20.6 | HIP 106668 | 11.31 |
| 2026-08-17 12:00 | 21:36:20.63 | -54:38:17.8 | HIP 106577 | 11.30 |
| 2026-08-18 00:00 | 21:35:54.43 | -54:40:11.9 | HIP 106577 | 8.71 |
| 2026-08-18 12:00 | 21:35:28.22 | -54:42:03.0 | HIP 106577 | 7.70 |
| 2026-08-19 00:00 | 21:35:01.99 | -54:43:51.1 | HIP 106577 | 8.81 |