| 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 |
0.999 |
| 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) |
| 2026-07-29 00:00 |
11:49:33.61 |
+14:38:12.2 |
HIP 57632 |
8.16 |
| 2026-07-29 12:00 |
11:49:38.64 |
+14:37:24.8 |
HIP 57632 |
8.96 |
| 2026-07-30 00:00 |
11:49:43.74 |
+14:36:37.3 |
HIP 57632 |
9.91 |
| 2026-07-30 12:00 |
11:49:48.88 |
+14:35:49.7 |
HIP 57632 |
10.99 |
| 2026-07-31 00:00 |
11:49:54.08 |
+14:35:01.9 |
HIP 57632 |
12.17 |
| 2026-07-31 12:00 |
11:49:59.33 |
+14:34:14.0 |
HIP 57632 |
13.42 |
| 2026-08-01 00:00 |
11:50:04.63 |
+14:33:26.0 |
HIP 57632 |
14.73 |
| 2026-08-01 12:00 |
11:50:09.99 |
+14:32:37.9 |
HIP 57632 |
16.09 |
| 2026-08-02 00:00 |
11:50:15.39 |
+14:31:49.7 |
HIP 57632 |
17.49 |
| 2026-08-02 12:00 |
11:50:20.85 |
+14:31:01.3 |
HIP 57632 |
18.92 |
| 2026-08-03 00:00 |
11:50:26.36 |
+14:30:12.9 |
HIP 57632 |
20.38 |
| 2026-08-03 12:00 |
11:50:31.92 |
+14:29:24.4 |
HIP 57632 |
21.87 |
| 2026-08-04 00:00 |
11:50:37.53 |
+14:28:35.7 |
HIP 57632 |
23.38 |
| 2026-08-04 12:00 |
11:50:43.19 |
+14:27:47.0 |
HIP 57891 |
24.59 |
| 2026-08-05 00:00 |
11:50:48.89 |
+14:26:58.2 |
HIP 57891 |
23.21 |
| 2026-08-05 12:00 |
11:50:54.65 |
+14:26:09.3 |
HIP 57891 |
21.86 |
| 2026-08-06 00:00 |
11:51:00.45 |
+14:25:20.3 |
HIP 57891 |
20.53 |
| 2026-08-06 12:00 |
11:51:06.30 |
+14:24:31.3 |
HIP 57891 |
19.23 |
| 2026-08-07 00:00 |
11:51:12.20 |
+14:23:42.1 |
HIP 57891 |
17.98 |
| 2026-08-07 12:00 |
11:51:18.14 |
+14:22:52.9 |
HIP 57891 |
16.78 |
| 2026-08-08 00:00 |
11:51:24.13 |
+14:22:03.7 |
HIP 57891 |
15.66 |
| 2026-08-08 12:00 |
11:51:30.17 |
+14:21:14.3 |
HIP 57891 |
14.63 |
| 2026-08-09 00:00 |
11:51:36.25 |
+14:20:25.0 |
HIP 57891 |
13.72 |
| 2026-08-09 12:00 |
11:51:42.38 |
+14:19:35.5 |
HIP 57891 |
12.96 |
| 2026-08-10 00:00 |
11:51:48.55 |
+14:18:46.0 |
HIP 57891 |
12.38 |
| 2026-08-10 12:00 |
11:51:54.76 |
+14:17:56.5 |
HIP 57906 |
11.70 |
| 2026-08-11 00:00 |
11:52:01.02 |
+14:17:06.9 |
HIP 57906 |
9.98 |
| 2026-08-11 12:00 |
11:52:07.31 |
+14:16:17.3 |
HIP 57906 |
8.25 |
| 2026-08-12 00:00 |
11:52:13.66 |
+14:15:27.7 |
HIP 57906 |
6.51 |
| 2026-08-12 12:00 |
11:52:20.04 |
+14:14:38.0 |
HIP 57906 |
4.76 |
| 2026-08-13 00:00 |
11:52:26.46 |
+14:13:48.3 |
HIP 57906 |
3.02 |
| 2026-08-13 12:00 |
11:52:32.93 |
+14:12:58.6 |
HIP 57906 |
1.31 |
| 2026-08-14 00:00 |
11:52:39.43 |
+14:12:08.8 |
HIP 57906 |
0.78 |
| 2026-08-14 12:00 |
11:52:45.98 |
+14:11:19.1 |
HIP 57906 |
2.43 |
| 2026-08-15 00:00 |
11:52:52.56 |
+14:10:29.3 |
HIP 57906 |
4.20 |
| 2026-08-15 12:00 |
11:52:59.18 |
+14:09:39.5 |
HIP 57906 |
6.00 |
| 2026-08-16 00:00 |
11:53:05.84 |
+14:08:49.8 |
HIP 57906 |
7.81 |
| 2026-08-16 12:00 |
11:53:12.53 |
+14:08:00.0 |
HIP 57906 |
9.62 |
| 2026-08-17 00:00 |
11:53:19.26 |
+14:07:10.3 |
HIP 58006 |
9.49 |
| 2026-08-17 12:00 |
11:53:26.03 |
+14:06:20.6 |
HIP 58006 |
7.67 |
| 2026-08-18 00:00 |
11:53:32.84 |
+14:05:30.8 |
HIP 58006 |
5.86 |
| 2026-08-18 12:00 |
11:53:39.67 |
+14:04:41.2 |
HIP 58006 |
4.08 |
| 2026-08-19 00:00 |
11:53:46.55 |
+14:03:51.5 |
HIP 58006 |
2.40 |