P/2021 N2 (Fuls)
Metadata
| Parameter | Value |
|---|---|
| Designation | P/2021 N2 (Fuls) |
| Type | P |
| Perihelion (tp_cal, UTC) | 2021-11-13T08:47:40.061760Z |
| Orbit solution date (soln_date, UTC) | 2024-04-13T16:42:58Z |
| Obs used | 1068 |
| NEO | - |
| M1 | 10.700 |
| K1 | 6.000 |
| PC | - |
| Discovery observation (MPC, UTC) | 2021-07-09T10:28:20.640000Z |
| Discovery magnitude (MPC) | 18.31 G |
| Discovery observatory (MPC) | 703 · University of Arizona Catalina Sky Survey |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2022-02-21.0000000 |
| e | 0.45237346 |
| q (au) | 3.796615 |
| a (au) | 6.932854 |
| i (deg) | 13.062899 |
| Ω (om, deg) | 221.742530 |
| ω (w, deg) | 177.355783 |
| M (ma, deg) | 5.379497 |
Magnitude
Scatter + Global Linear
$$ M_a = (11.970 + 2.872\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 11.970 |
| n | 2.872 |
| gf | 1.000 |
| gb | -0.655 |
| 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 |
|---|---|---|---|
| 2021-11-13 | 2022-11-22 | +8.2745 | -5.398 |
| 2022-11-22 | 2026-07-26 | -7.2967 | +4.795 |
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) |
|---|---|---|---|---|
| 2026-09-20 00:00 | 11:45:11.57 | -06:59:53.0 | HIP 57405 | 25.69 |
| 2026-09-20 12:00 | 11:45:26.54 | -07:01:20.6 | HIP 57405 | 25.19 |
| 2026-09-21 00:00 | 11:45:41.51 | -07:02:48.3 | HIP 57405 | 25.33 |
| 2026-09-21 12:00 | 11:45:56.47 | -07:04:16.2 | HIP 57405 | 26.08 |
| 2026-09-22 00:00 | 11:46:11.42 | -07:05:44.3 | HIP 57405 | 27.41 |
| 2026-09-22 12:00 | 11:46:26.37 | -07:07:12.5 | HIP 57405 | 29.22 |
| 2026-09-23 00:00 | 11:46:41.32 | -07:08:40.9 | HIP 57405 | 31.44 |
| 2026-09-23 12:00 | 11:46:56.25 | -07:10:09.4 | HIP 57405 | 33.99 |
| 2026-09-24 00:00 | 11:47:11.18 | -07:11:38.1 | HIP 57641 | 31.30 |
| 2026-09-24 12:00 | 11:47:26.10 | -07:13:06.9 | HIP 57641 | 27.33 |
| 2026-09-25 00:00 | 11:47:41.01 | -07:14:35.8 | HIP 57641 | 23.35 |
| 2026-09-25 12:00 | 11:47:55.91 | -07:16:04.9 | HIP 57641 | 19.38 |
| 2026-09-26 00:00 | 11:48:10.80 | -07:17:34.2 | HIP 57641 | 15.42 |
| 2026-09-26 12:00 | 11:48:25.68 | -07:19:03.5 | HIP 57641 | 11.48 |
| 2026-09-27 00:00 | 11:48:40.55 | -07:20:33.0 | HIP 57641 | 7.58 |
| 2026-09-27 12:00 | 11:48:55.41 | -07:22:02.7 | HIP 57641 | 3.84 |
| 2026-09-28 00:00 | 11:49:10.26 | -07:23:32.4 | HIP 57641 | 1.91 |
| 2026-09-28 12:00 | 11:49:25.10 | -07:25:02.3 | HIP 57641 | 4.91 |
| 2026-09-29 00:00 | 11:49:39.92 | -07:26:32.2 | HIP 57641 | 8.73 |
| 2026-09-29 12:00 | 11:49:54.73 | -07:28:02.3 | HIP 57730 | 8.08 |
| 2026-09-30 00:00 | 11:50:09.53 | -07:29:32.5 | HIP 57730 | 7.35 |
| 2026-09-30 12:00 | 11:50:24.31 | -07:31:02.8 | HIP 57730 | 8.60 |
| 2026-10-01 00:00 | 11:50:39.08 | -07:32:33.2 | HIP 57730 | 11.20 |
| 2026-10-01 12:00 | 11:50:53.83 | -07:34:03.7 | HIP 57730 | 14.43 |
| 2026-10-02 00:00 | 11:51:08.57 | -07:35:34.3 | HIP 57730 | 17.95 |
| 2026-10-02 12:00 | 11:51:23.29 | -07:37:05.0 | HIP 57917 | 20.31 |
| 2026-10-03 00:00 | 11:51:37.99 | -07:38:35.8 | HIP 57917 | 16.86 |
| 2026-10-03 12:00 | 11:51:52.68 | -07:40:06.6 | HIP 57917 | 13.69 |
| 2026-10-04 00:00 | 11:52:07.35 | -07:41:37.6 | HIP 57917 | 11.02 |
| 2026-10-04 12:00 | 11:52:22.00 | -07:43:08.6 | HIP 57917 | 9.31 |
| 2026-10-05 00:00 | 11:52:36.64 | -07:44:39.7 | HIP 57917 | 9.11 |
| 2026-10-05 12:00 | 11:52:51.25 | -07:46:10.9 | HIP 57917 | 10.49 |
| 2026-10-06 00:00 | 11:53:05.84 | -07:47:42.1 | HIP 57917 | 12.96 |
| 2026-10-06 12:00 | 11:53:20.42 | -07:49:13.4 | HIP 57917 | 16.02 |
| 2026-10-07 00:00 | 11:53:34.97 | -07:50:44.7 | HIP 57917 | 19.39 |
| 2026-10-07 12:00 | 11:53:49.50 | -07:52:16.1 | HIP 57917 | 22.93 |
| 2026-10-08 00:00 | 11:54:04.01 | -07:53:47.6 | HIP 57917 | 26.57 |
| 2026-10-08 12:00 | 11:54:18.49 | -07:55:19.1 | HIP 58163 | 26.81 |
| 2026-10-09 00:00 | 11:54:32.96 | -07:56:50.6 | HIP 58163 | 23.10 |
| 2026-10-09 12:00 | 11:54:47.39 | -07:58:22.1 | HIP 58163 | 19.45 |
| 2026-10-10 00:00 | 11:55:01.81 | -07:59:53.7 | HIP 58163 | 15.93 |
| 2026-10-10 12:00 | 11:55:16.19 | -08:01:25.4 | HIP 58163 | 12.62 |
| 2026-10-11 00:00 | 11:55:30.56 | -08:02:57.0 | HIP 58163 | 9.74 |