| 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 |
-4.0345 |
+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) |
| 2026-06-01 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 |
| 2026-06-02 12:00 |
22:44:23.85 |
-26:00:00.2 |
HIP 112272 |
17.59 |
| 2026-06-03 00:00 |
22:44:26.30 |
-26:01:27.4 |
HIP 112272 |
16.11 |
| 2026-06-03 12:00 |
22:44:28.64 |
-26:02:55.1 |
HIP 112272 |
14.64 |
| 2026-06-04 00:00 |
22:44:30.86 |
-26:04:23.6 |
HIP 112272 |
13.17 |
| 2026-06-04 12:00 |
22:44:32.98 |
-26:05:52.7 |
HIP 112272 |
11.71 |
| 2026-06-05 00:00 |
22:44:34.99 |
-26:07:22.4 |
HIP 112272 |
10.27 |
| 2026-06-05 12:00 |
22:44:36.89 |
-26:08:52.7 |
HIP 112272 |
8.86 |
| 2026-06-06 00:00 |
22:44:38.68 |
-26:10:23.7 |
HIP 112272 |
7.49 |
| 2026-06-06 12:00 |
22:44:40.36 |
-26:11:55.3 |
HIP 112272 |
6.19 |
| 2026-06-07 00:00 |
22:44:41.93 |
-26:13:27.6 |
HIP 112272 |
5.03 |
| 2026-06-07 12:00 |
22:44:43.39 |
-26:15:00.4 |
HIP 112272 |
4.12 |
| 2026-06-08 00:00 |
22:44:44.73 |
-26:16:33.9 |
HIP 112272 |
3.68 |
| 2026-06-08 12:00 |
22:44:45.97 |
-26:18:08.0 |
HIP 112272 |
3.86 |
| 2026-06-09 00:00 |
22:44:47.09 |
-26:19:42.7 |
HIP 112272 |
4.61 |
| 2026-06-09 12:00 |
22:44:48.11 |
-26:21:18.1 |
HIP 112272 |
5.70 |
| 2026-06-10 00:00 |
22:44:49.01 |
-26:22:54.0 |
HIP 112272 |
6.99 |
| 2026-06-10 12:00 |
22:44:49.80 |
-26:24:30.5 |
HIP 112272 |
8.38 |
| 2026-06-11 00:00 |
22:44:50.48 |
-26:26:07.6 |
HIP 112272 |
9.84 |
| 2026-06-11 12:00 |
22:44:51.04 |
-26:27:45.3 |
HIP 112272 |
11.34 |
| 2026-06-12 00:00 |
22:44:51.50 |
-26:29:23.6 |
HIP 112272 |
12.87 |
| 2026-06-12 12:00 |
22:44:51.84 |
-26:31:02.5 |
HIP 112272 |
14.43 |
| 2026-06-13 00:00 |
22:44:52.07 |
-26:32:41.9 |
HIP 112272 |
16.01 |
| 2026-06-13 12:00 |
22:44:52.18 |
-26:34:21.9 |
HIP 112272 |
17.60 |
| 2026-06-14 00:00 |
22:44:52.19 |
-26:36:02.5 |
HIP 112272 |
19.21 |
| 2026-06-14 12:00 |
22:44:52.08 |
-26:37:43.6 |
HIP 112272 |
20.83 |
| 2026-06-15 00:00 |
22:44:51.86 |
-26:39:25.3 |
HIP 112383 |
22.37 |
| 2026-06-15 12:00 |
22:44:51.52 |
-26:41:07.5 |
HIP 112383 |
20.95 |
| 2026-06-16 00:00 |
22:44:51.08 |
-26:42:50.3 |
HIP 112383 |
19.59 |
| 2026-06-16 12:00 |
22:44:50.52 |
-26:44:33.6 |
HIP 112383 |
18.30 |
| 2026-06-17 00:00 |
22:44:49.85 |
-26:46:17.4 |
HIP 112383 |
17.09 |
| 2026-06-17 12:00 |
22:44:49.06 |
-26:48:01.8 |
HIP 112233 |
15.90 |
| 2026-06-18 00:00 |
22:44:48.17 |
-26:49:46.6 |
HIP 112233 |
14.79 |
| 2026-06-18 12:00 |
22:44:47.16 |
-26:51:32.0 |
HIP 112233 |
13.78 |
| 2026-06-19 00:00 |
22:44:46.04 |
-26:53:17.8 |
HIP 112233 |
12.90 |
| 2026-06-19 12:00 |
22:44:44.81 |
-26:55:04.2 |
HIP 112233 |
12.20 |
| 2026-06-20 00:00 |
22:44:43.47 |
-26:56:51.0 |
HIP 112256 |
11.44 |
| 2026-06-20 12:00 |
22:44:42.02 |
-26:58:38.3 |
HIP 112256 |
9.85 |
| 2026-06-21 00:00 |
22:44:40.45 |
-27:00:26.1 |
HIP 112256 |
8.32 |
| 2026-06-21 12:00 |
22:44:38.77 |
-27:02:14.3 |
HIP 112256 |
6.92 |
| 2026-06-22 00:00 |
22:44:36.99 |
-27:04:03.0 |
HIP 112256 |
5.75 |