C/2020 F3 (NEOWISE)
Metadata
| Parameter | Value |
|---|---|
| Designation | C/2020 F3 (NEOWISE) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2020-07-03T16:17:36.787200Z |
| Orbit solution date (soln_date, UTC) | 2024-07-30T14:57:24Z |
| Obs used | 1315 |
| NEO | - |
| M1 | 12.100 |
| K1 | 12.250 |
| PC | - |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2020-07-06.0000000 |
| e | 0.99917803 |
| q (au) | 0.294651 |
| a (au) | 358.467957 |
| i (deg) | 128.937503 |
| Ω (om, deg) | 61.010428 |
| ω (w, deg) | 37.278658 |
| M (ma, deg) | 0.000337 |
Magnitude
Scatter + Global Linear
$$ M_a = (8.535 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 8.535 |
| n | 6.000 |
| gf | 1.000 |
| 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 |
|---|---|---|---|
| 2020-03-27 | 2020-04-22 | +19.1066 | -3.757 |
| 2020-04-22 | 2020-05-07 | +13.0268 | -2.831 |
| 2020-05-07 | 2020-07-03 | +0.2884 | -1.478 |
| 2020-07-04 | 2020-07-17 | +2.2790 | +1.205 |
| 2020-07-17 | 2023-04-14 | -6.6559 | -0.824 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) | RA (J2000) | Dec (J2000) | Nearest HIP | Dist from HIP (arcmin) |
|---|---|---|---|---|
| 2026-06-01 00:00 | 14:23:30.28 | -33:45:56.2 | HIP 70407 | 13.46 |
| 2026-06-01 12:00 | 14:23:23.45 | -33:45:13.7 | HIP 70407 | 14.96 |
| 2026-06-02 00:00 | 14:23:16.66 | -33:44:31.2 | HIP 70407 | 16.47 |
| 2026-06-02 12:00 | 14:23:09.91 | -33:43:48.5 | HIP 70407 | 17.99 |
| 2026-06-03 00:00 | 14:23:03.20 | -33:43:05.8 | HIP 70407 | 19.51 |
| 2026-06-03 12:00 | 14:22:56.54 | -33:42:22.9 | HIP 70407 | 21.03 |
| 2026-06-04 00:00 | 14:22:49.92 | -33:41:40.0 | HIP 70407 | 22.55 |
| 2026-06-04 12:00 | 14:22:43.34 | -33:40:57.1 | HIP 70407 | 24.07 |
| 2026-06-05 00:00 | 14:22:36.81 | -33:40:14.0 | HIP 70407 | 25.58 |
| 2026-06-05 12:00 | 14:22:30.33 | -33:39:30.9 | HIP 70407 | 27.09 |
| 2026-06-06 00:00 | 14:22:23.89 | -33:38:47.7 | HIP 70407 | 28.60 |
| 2026-06-06 12:00 | 14:22:17.49 | -33:38:04.5 | HIP 70407 | 30.10 |
| 2026-06-07 00:00 | 14:22:11.14 | -33:37:21.2 | HIP 70407 | 31.59 |
| 2026-06-07 12:00 | 14:22:04.84 | -33:36:37.8 | HIP 70407 | 33.08 |
| 2026-06-08 00:00 | 14:21:58.59 | -33:35:54.4 | HIP 70407 | 34.56 |
| 2026-06-08 12:00 | 14:21:52.38 | -33:35:11.0 | HIP 70407 | 36.03 |
| 2026-06-09 00:00 | 14:21:46.22 | -33:34:27.5 | HIP 70407 | 37.50 |
| 2026-06-09 12:00 | 14:21:40.11 | -33:33:44.0 | HIP 70407 | 38.96 |
| 2026-06-10 00:00 | 14:21:34.05 | -33:33:00.5 | HIP 70407 | 40.41 |
| 2026-06-10 12:00 | 14:21:28.04 | -33:32:16.9 | HIP 70407 | 41.85 |
| 2026-06-11 00:00 | 14:21:22.07 | -33:31:33.3 | HIP 69904 | 41.49 |
| 2026-06-11 12:00 | 14:21:16.16 | -33:30:49.7 | HIP 69904 | 40.06 |
| 2026-06-12 00:00 | 14:21:10.30 | -33:30:06.1 | HIP 69904 | 38.64 |
| 2026-06-12 12:00 | 14:21:04.49 | -33:29:22.5 | HIP 69904 | 37.24 |
| 2026-06-13 00:00 | 14:20:58.73 | -33:28:38.8 | HIP 69904 | 35.84 |
| 2026-06-13 12:00 | 14:20:53.02 | -33:27:55.2 | HIP 69904 | 34.45 |
| 2026-06-14 00:00 | 14:20:47.37 | -33:27:11.5 | HIP 69904 | 33.08 |
| 2026-06-14 12:00 | 14:20:41.76 | -33:26:27.9 | HIP 69904 | 31.71 |
| 2026-06-15 00:00 | 14:20:36.21 | -33:25:44.3 | HIP 69904 | 30.36 |
| 2026-06-15 12:00 | 14:20:30.72 | -33:25:00.7 | HIP 69904 | 29.01 |
| 2026-06-16 00:00 | 14:20:25.27 | -33:24:17.1 | HIP 69904 | 27.68 |
| 2026-06-16 12:00 | 14:20:19.89 | -33:23:33.6 | HIP 69904 | 26.36 |
| 2026-06-17 00:00 | 14:20:14.55 | -33:22:50.0 | HIP 69904 | 25.06 |
| 2026-06-17 12:00 | 14:20:09.27 | -33:22:06.5 | HIP 69904 | 23.76 |
| 2026-06-18 00:00 | 14:20:04.05 | -33:21:23.1 | HIP 69904 | 22.48 |
| 2026-06-18 12:00 | 14:19:58.88 | -33:20:39.7 | HIP 69904 | 21.21 |
| 2026-06-19 00:00 | 14:19:53.76 | -33:19:56.3 | HIP 69904 | 19.96 |
| 2026-06-19 12:00 | 14:19:48.70 | -33:19:13.0 | HIP 69904 | 18.73 |
| 2026-06-20 00:00 | 14:19:43.70 | -33:18:29.7 | HIP 69904 | 17.51 |
| 2026-06-20 12:00 | 14:19:38.76 | -33:17:46.5 | HIP 69904 | 16.32 |
| 2026-06-21 00:00 | 14:19:33.87 | -33:17:03.4 | HIP 69904 | 15.14 |
| 2026-06-21 12:00 | 14:19:29.04 | -33:16:20.3 | HIP 69904 | 13.99 |
| 2026-06-22 00:00 | 14:19:24.26 | -33:15:37.3 | HIP 69904 | 12.87 |