| Parameter |
Value |
| Designation |
C/2022 P1 (NEOWISE) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2022-11-28T11:23:56.353920Z |
| Orbit solution date (soln_date, UTC) |
2023-06-30T22:17:01Z |
| Obs used |
696 |
| NEO |
- |
| M1 |
11.500 |
| K1 |
13.250 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2022-08-08T08:24:35.424000Z |
| Discovery magnitude (MPC) |
18.00 R |
| Discovery observatory (MPC) |
C51 · WISE |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2022-10-18.0000000 |
| e |
0.91345543 |
| q (au) |
1.595184 |
| a (au) |
18.431934 |
| i (deg) |
154.606664 |
| Ω (om, deg) |
205.081648 |
| ω (w, deg) |
249.934454 |
| M (ma, deg) |
359.483425 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.149 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.149 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.999 |
| 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 |
| 2022-08-08 |
2022-11-26 |
+30.4030 |
-9.310 |
| 2022-12-07 |
2023-06-16 |
+15.1448 |
-6.764 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
11:52:02.55 |
+15:29:37.2 |
HIP 57920 |
11.06 |
| 2026-05-12 12:00 |
11:51:54.59 |
+15:30:01.4 |
HIP 57920 |
13.01 |
| 2026-05-13 00:00 |
11:51:46.73 |
+15:30:24.9 |
HIP 57920 |
14.94 |
| 2026-05-13 12:00 |
11:51:38.95 |
+15:30:47.6 |
HIP 57920 |
16.85 |
| 2026-05-14 00:00 |
11:51:31.27 |
+15:31:09.6 |
HIP 57752 |
17.73 |
| 2026-05-14 12:00 |
11:51:23.68 |
+15:31:30.8 |
HIP 57752 |
16.23 |
| 2026-05-15 00:00 |
11:51:16.19 |
+15:31:51.3 |
HIP 57752 |
14.83 |
| 2026-05-15 12:00 |
11:51:08.79 |
+15:32:11.0 |
HIP 57752 |
13.56 |
| 2026-05-16 00:00 |
11:51:01.48 |
+15:32:30.0 |
HIP 57752 |
12.45 |
| 2026-05-16 12:00 |
11:50:54.27 |
+15:32:48.2 |
HIP 57752 |
11.53 |
| 2026-05-17 00:00 |
11:50:47.16 |
+15:33:05.8 |
HIP 57752 |
10.83 |
| 2026-05-17 12:00 |
11:50:40.13 |
+15:33:22.5 |
HIP 57752 |
10.40 |
| 2026-05-18 00:00 |
11:50:33.21 |
+15:33:38.6 |
HIP 57752 |
10.24 |
| 2026-05-18 12:00 |
11:50:26.37 |
+15:33:53.9 |
HIP 57752 |
10.37 |
| 2026-05-19 00:00 |
11:50:19.64 |
+15:34:08.4 |
HIP 57752 |
10.76 |
| 2026-05-19 12:00 |
11:50:13.00 |
+15:34:22.3 |
HIP 57752 |
11.36 |
| 2026-05-20 00:00 |
11:50:06.45 |
+15:34:35.4 |
HIP 57752 |
12.15 |
| 2026-05-20 12:00 |
11:50:00.00 |
+15:34:47.9 |
HIP 57752 |
13.08 |
| 2026-05-21 00:00 |
11:49:53.65 |
+15:34:59.6 |
HIP 57752 |
14.11 |
| 2026-05-21 12:00 |
11:49:47.39 |
+15:35:10.6 |
HIP 57752 |
15.21 |
| 2026-05-22 00:00 |
11:49:41.23 |
+15:35:20.9 |
HIP 57752 |
16.37 |
| 2026-05-22 12:00 |
11:49:35.17 |
+15:35:30.5 |
HIP 57752 |
17.56 |
| 2026-05-23 00:00 |
11:49:29.20 |
+15:35:39.4 |
HIP 57752 |
18.77 |
| 2026-05-23 12:00 |
11:49:23.33 |
+15:35:47.6 |
HIP 57752 |
20.00 |
| 2026-05-24 00:00 |
11:49:17.55 |
+15:35:55.1 |
HIP 57752 |
21.24 |
| 2026-05-24 12:00 |
11:49:11.88 |
+15:36:01.9 |
HIP 57635 |
22.23 |
| 2026-05-25 00:00 |
11:49:06.29 |
+15:36:08.1 |
HIP 57635 |
22.27 |
| 2026-05-25 12:00 |
11:49:00.81 |
+15:36:13.5 |
HIP 57635 |
22.38 |
| 2026-05-26 00:00 |
11:48:55.42 |
+15:36:18.3 |
HIP 57635 |
22.56 |
| 2026-05-26 12:00 |
11:48:50.12 |
+15:36:22.5 |
HIP 57635 |
22.80 |
| 2026-05-27 00:00 |
11:48:44.93 |
+15:36:25.9 |
HIP 57635 |
23.08 |
| 2026-05-27 12:00 |
11:48:39.83 |
+15:36:28.7 |
HIP 57635 |
23.42 |
| 2026-05-28 00:00 |
11:48:34.82 |
+15:36:30.9 |
HIP 57635 |
23.79 |
| 2026-05-28 12:00 |
11:48:29.91 |
+15:36:32.4 |
HIP 57635 |
24.20 |
| 2026-05-29 00:00 |
11:48:25.10 |
+15:36:33.2 |
HIP 57635 |
24.65 |
| 2026-05-29 12:00 |
11:48:20.38 |
+15:36:33.4 |
HIP 57635 |
25.12 |
| 2026-05-30 00:00 |
11:48:15.76 |
+15:36:33.0 |
HIP 57635 |
25.61 |
| 2026-05-30 12:00 |
11:48:11.24 |
+15:36:31.9 |
HIP 57635 |
26.11 |
| 2026-05-31 00:00 |
11:48:06.81 |
+15:36:30.2 |
HIP 57635 |
26.64 |
| 2026-05-31 12:00 |
11:48:02.47 |
+15:36:27.9 |
HIP 57635 |
27.17 |
| 2026-06-01 00:00 |
11:47:58.24 |
+15:36:24.9 |
HIP 57635 |
27.71 |
| 2026-06-01 12:00 |
11:47:54.10 |
+15:36:21.3 |
HIP 57635 |
28.25 |
| 2026-06-02 00:00 |
11:47:50.05 |
+15:36:17.1 |
HIP 57635 |
28.80 |