C/2022 U3 (Bok)

Metadata

Parameter Value
Designation C/2022 U3 (Bok)
Type C
Perihelion (tp_cal, UTC) 2024-07-28T01:29:51.809280Z
Orbit solution date (soln_date, UTC) 2026-03-07T14:42:53Z
Obs used 803
NEO -
M1 8.800
K1 8.500
PC 0.030
Discovery observation (MPC, UTC) 2022-10-31T06:16:30.662400Z
Discovery magnitude (MPC) 19.66 G
Discovery observatory (MPC) V00 · Kitt Peak-Bok
Osculating Elements
Parameter Value
Epoch (epoch_cal, TDB) 2023-12-18.0000000
e 1.00318343
q (au) 4.826915
a (au) -1516.261844
i (deg) 33.638233
Ω (om, deg) 272.788587
ω (w, deg) 189.047254
M (ma, deg) -0.003724

Magnitude

C/2022 U3 (Bok) · Magnitude (Full range)

Scatter + Global Linear

$$ M_a = (7.781 + 3.427\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

Model Parameters

Parameter Value
H0 7.781
n 3.427
gf 1.000
gb -1.000
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
2021-06-23 2024-04-10 +2.0797 -1.688
2024-09-14 2026-02-07 +7.5196 -4.311

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 09:45:37.38 -21:34:10.3 HIP 47910 11.87
2026-06-01 12:00 09:45:49.08 -21:33:22.6 HIP 47931 11.53
2026-06-02 00:00 09:46:00.88 -21:32:35.9 HIP 47931 10.24
2026-06-02 12:00 09:46:12.78 -21:31:50.2 HIP 47931 9.67
2026-06-03 00:00 09:46:24.79 -21:31:05.4 HIP 47931 9.96
2026-06-03 12:00 09:46:36.89 -21:30:21.6 HIP 47931 11.06
2026-06-04 00:00 09:46:49.10 -21:29:38.7 HIP 47931 12.77
2026-06-04 12:00 09:47:01.41 -21:28:56.9 HIP 48005 13.18
2026-06-05 00:00 09:47:13.82 -21:28:16.0 HIP 48005 13.85
2026-06-05 12:00 09:47:26.33 -21:27:36.1 HIP 48005 15.07
2026-06-06 00:00 09:47:38.94 -21:26:57.1 HIP 48005 16.73
2026-06-06 12:00 09:47:51.64 -21:26:19.2 HIP 48005 18.73
2026-06-07 00:00 09:48:04.45 -21:25:42.3 HIP 48005 20.98
2026-06-07 12:00 09:48:17.35 -21:25:06.3 HIP 48005 23.41
2026-06-08 00:00 09:48:30.34 -21:24:31.3 HIP 48005 25.97
2026-06-08 12:00 09:48:43.43 -21:23:57.3 HIP 48231 24.17
2026-06-09 00:00 09:48:56.62 -21:23:24.4 HIP 48231 21.58
2026-06-09 12:00 09:49:09.90 -21:22:52.4 HIP 48231 19.15
2026-06-10 00:00 09:49:23.27 -21:22:21.4 HIP 48231 16.97
2026-06-10 12:00 09:49:36.74 -21:21:51.4 HIP 48231 15.13
2026-06-11 00:00 09:49:50.30 -21:21:22.5 HIP 48231 13.81
2026-06-11 12:00 09:50:03.95 -21:20:54.5 HIP 48296 12.46
2026-06-12 00:00 09:50:17.69 -21:20:27.5 HIP 48296 10.26
2026-06-12 12:00 09:50:31.52 -21:20:01.6 HIP 48296 8.70
2026-06-13 00:00 09:50:45.44 -21:19:36.7 HIP 48296 8.19
2026-06-13 12:00 09:50:59.45 -21:19:12.8 HIP 48296 8.92
2026-06-14 00:00 09:51:13.54 -21:18:49.9 HIP 48296 10.65
2026-06-14 12:00 09:51:27.73 -21:18:28.0 HIP 48296 13.01
2026-06-15 00:00 09:51:42.00 -21:18:07.2 HIP 48296 15.73
2026-06-15 12:00 09:51:56.36 -21:17:47.3 HIP 48296 18.66
2026-06-16 00:00 09:52:10.80 -21:17:28.5 HIP 48323 20.95
2026-06-16 12:00 09:52:25.32 -21:17:10.8 HIP 48323 23.49
2026-06-17 00:00 09:52:39.93 -21:16:54.0 HIP 48323 26.25
2026-06-17 12:00 09:52:54.62 -21:16:38.3 HIP 48480 28.99
2026-06-18 00:00 09:53:09.39 -21:16:23.6 HIP 48480 28.38
2026-06-18 12:00 09:53:24.25 -21:16:09.9 HIP 48480 28.20
2026-06-19 00:00 09:53:39.18 -21:15:57.3 HIP 48480 28.46
2026-06-19 12:00 09:53:54.19 -21:15:45.7 HIP 48480 29.17
2026-06-20 00:00 09:54:09.29 -21:15:35.1 HIP 48480 30.29
2026-06-20 12:00 09:54:24.45 -21:15:25.5 HIP 48747 30.17
2026-06-21 00:00 09:54:39.70 -21:15:17.0 HIP 48747 26.62
2026-06-21 12:00 09:54:55.02 -21:15:09.4 HIP 48747 23.05
2026-06-22 00:00 09:55:10.42 -21:15:02.9 HIP 48747 19.47