| Parameter |
Value |
| Designation |
C/2022 U4 (Bok) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2023-08-03T16:19:50.327040Z |
| Orbit solution date (soln_date, UTC) |
2023-11-18T17:43:20Z |
| Obs used |
691 |
| NEO |
- |
| M1 |
12.200 |
| K1 |
8.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2022-10-26T11:34:51.024000Z |
| Discovery magnitude (MPC) |
20.21 G |
| Discovery observatory (MPC) |
V00 · Kitt Peak-Bok |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2023-04-13.0000000 |
| e |
0.99921142 |
| q (au) |
2.898398 |
| a (au) |
3675.478615 |
| i (deg) |
52.035423 |
| Ω (om, deg) |
132.928981 |
| ω (w, deg) |
89.007568 |
| M (ma, deg) |
359.999502 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.000 + 5.079\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.000 |
| n |
5.079 |
| gf |
1.000 |
| gb |
-0.736 |
| 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 |
| 2022-01-07 |
2023-02-26 |
+3.2013 |
-2.039 |
| 2023-02-26 |
2023-08-02 |
-4.0360 |
+2.011 |
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 |
22:40:58.41 |
-25:08:26.0 |
HIP 112015 |
13.72 |
| 2026-05-12 12:00 |
22:41:05.34 |
-25:09:22.9 |
HIP 112015 |
12.28 |
| 2026-05-13 00:00 |
22:41:12.16 |
-25:10:20.4 |
HIP 112015 |
10.94 |
| 2026-05-13 12:00 |
22:41:18.89 |
-25:11:18.7 |
HIP 112015 |
9.74 |
| 2026-05-14 00:00 |
22:41:25.52 |
-25:12:17.8 |
HIP 112015 |
8.75 |
| 2026-05-14 12:00 |
22:41:32.05 |
-25:13:17.6 |
HIP 112015 |
8.01 |
| 2026-05-15 00:00 |
22:41:38.49 |
-25:14:18.1 |
HIP 112015 |
7.61 |
| 2026-05-15 12:00 |
22:41:44.82 |
-25:15:19.4 |
HIP 112015 |
7.59 |
| 2026-05-16 00:00 |
22:41:51.05 |
-25:16:21.4 |
HIP 112015 |
7.94 |
| 2026-05-16 12:00 |
22:41:57.18 |
-25:17:24.1 |
HIP 112015 |
8.61 |
| 2026-05-17 00:00 |
22:42:03.21 |
-25:18:27.5 |
HIP 112015 |
9.52 |
| 2026-05-17 12:00 |
22:42:09.14 |
-25:19:31.7 |
HIP 112015 |
10.62 |
| 2026-05-18 00:00 |
22:42:14.97 |
-25:20:36.6 |
HIP 112015 |
11.84 |
| 2026-05-18 12:00 |
22:42:20.70 |
-25:21:42.3 |
HIP 112015 |
13.14 |
| 2026-05-19 00:00 |
22:42:26.32 |
-25:22:48.7 |
HIP 112015 |
14.50 |
| 2026-05-19 12:00 |
22:42:31.84 |
-25:23:55.8 |
HIP 112015 |
15.91 |
| 2026-05-20 00:00 |
22:42:37.26 |
-25:25:03.6 |
HIP 112137 |
16.21 |
| 2026-05-20 12:00 |
22:42:42.58 |
-25:26:12.1 |
HIP 112137 |
14.86 |
| 2026-05-21 00:00 |
22:42:47.79 |
-25:27:21.4 |
HIP 112137 |
13.57 |
| 2026-05-21 12:00 |
22:42:52.90 |
-25:28:31.4 |
HIP 112137 |
12.36 |
| 2026-05-22 00:00 |
22:42:57.91 |
-25:29:42.1 |
HIP 112181 |
11.00 |
| 2026-05-22 12:00 |
22:43:02.81 |
-25:30:53.5 |
HIP 112181 |
9.52 |
| 2026-05-23 00:00 |
22:43:07.60 |
-25:32:05.6 |
HIP 112181 |
8.08 |
| 2026-05-23 12:00 |
22:43:12.30 |
-25:33:18.5 |
HIP 112181 |
6.72 |
| 2026-05-24 00:00 |
22:43:16.88 |
-25:34:32.0 |
HIP 112181 |
5.48 |
| 2026-05-24 12:00 |
22:43:21.36 |
-25:35:46.3 |
HIP 112181 |
4.46 |
| 2026-05-25 00:00 |
22:43:25.74 |
-25:37:01.2 |
HIP 112181 |
3.83 |
| 2026-05-25 12:00 |
22:43:30.01 |
-25:38:16.9 |
HIP 112181 |
3.78 |
| 2026-05-26 00:00 |
22:43:34.18 |
-25:39:33.2 |
HIP 112181 |
4.33 |
| 2026-05-26 12:00 |
22:43:38.24 |
-25:40:50.2 |
HIP 112181 |
5.28 |
| 2026-05-27 00:00 |
22:43:42.19 |
-25:42:08.0 |
HIP 112181 |
6.47 |
| 2026-05-27 12:00 |
22:43:46.04 |
-25:43:26.4 |
HIP 112181 |
7.78 |
| 2026-05-28 00:00 |
22:43:49.78 |
-25:44:45.5 |
HIP 112181 |
9.15 |
| 2026-05-28 12:00 |
22:43:53.42 |
-25:46:05.3 |
HIP 112181 |
10.56 |
| 2026-05-29 00:00 |
22:43:56.95 |
-25:47:25.8 |
HIP 112181 |
12.00 |
| 2026-05-29 12:00 |
22:44:00.37 |
-25:48:46.9 |
HIP 112181 |
13.46 |
| 2026-05-30 00:00 |
22:44:03.68 |
-25:50:08.7 |
HIP 112181 |
14.92 |
| 2026-05-30 12:00 |
22:44:06.88 |
-25:51:31.2 |
HIP 112181 |
16.39 |
| 2026-05-31 00:00 |
22:44:09.98 |
-25:52:54.4 |
HIP 112181 |
17.87 |
| 2026-05-31 12:00 |
22:44:12.97 |
-25:54:18.2 |
HIP 112181 |
19.35 |
| 2026-06-01 00:00 |
22:44:15.86 |
-25:55:42.7 |
HIP 112181 |
20.83 |
| 2026-06-01 12:00 |
22:44:18.63 |
-25:57:07.9 |
HIP 112272 |
20.55 |
| 2026-06-02 00:00 |
22:44:21.29 |
-25:58:33.7 |
HIP 112272 |
19.07 |