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)
2026-09-20 00:00 10:51:29.93 -25:02:50.5 HIP 53010 30.53
2026-09-20 12:00 10:51:48.93 -25:05:13.8 HIP 53010 30.23
2026-09-21 00:00 10:52:07.90 -25:07:37.6 HIP 53095 29.96
2026-09-21 12:00 10:52:26.84 -25:10:02.0 HIP 53095 28.75
2026-09-22 00:00 10:52:45.74 -25:12:26.9 HIP 53095 28.34
2026-09-22 12:00 10:53:04.61 -25:14:52.3 HIP 53095 28.76
2026-09-23 00:00 10:53:23.45 -25:17:18.2 HIP 53095 29.97
2026-09-23 12:00 10:53:42.26 -25:19:44.6 HIP 53095 31.88
2026-09-24 00:00 10:54:01.03 -25:22:11.5 HIP 53468 33.06
2026-09-24 12:00 10:54:19.77 -25:24:39.0 HIP 53468 28.21
2026-09-25 00:00 10:54:38.47 -25:27:06.9 HIP 53468 23.38
2026-09-25 12:00 10:54:57.13 -25:29:35.4 HIP 53468 18.60
2026-09-26 00:00 10:55:15.76 -25:32:04.3 HIP 53468 13.89
2026-09-26 12:00 10:55:34.36 -25:34:33.7 HIP 53468 9.38
2026-09-27 00:00 10:55:52.91 -25:37:03.6 HIP 53468 5.54
2026-09-27 12:00 10:56:11.43 -25:39:34.0 HIP 53468 4.58
2026-09-28 00:00 10:56:29.91 -25:42:04.9 HIP 53468 7.67
2026-09-28 12:00 10:56:48.35 -25:44:36.3 HIP 53468 12.00
2026-09-29 00:00 10:57:06.75 -25:47:08.1 HIP 53468 16.62
2026-09-29 12:00 10:57:25.12 -25:49:40.4 HIP 53468 21.34
2026-09-30 00:00 10:57:43.44 -25:52:13.1 HIP 53658 19.33
2026-09-30 12:00 10:58:01.72 -25:54:46.4 HIP 53658 14.76
2026-10-01 00:00 10:58:19.96 -25:57:20.1 HIP 53658 10.43
2026-10-01 12:00 10:58:38.16 -25:59:54.2 HIP 53658 6.81
2026-10-02 00:00 10:58:56.31 -26:02:28.8 HIP 53658 5.53
2026-10-02 12:00 10:59:14.43 -26:05:03.8 HIP 53658 7.81
2026-10-03 00:00 10:59:32.50 -26:07:39.3 HIP 53658 11.73
2026-10-03 12:00 10:59:50.52 -26:10:15.3 HIP 53658 16.13
2026-10-04 00:00 11:00:08.50 -26:12:51.6 HIP 53658 20.70
2026-10-04 12:00 11:00:26.44 -26:15:28.4 HIP 53810 24.16
2026-10-05 00:00 11:00:44.33 -26:18:05.7 HIP 53810 26.81
2026-10-05 12:00 11:01:02.17 -26:20:43.3 HIP 53810 30.01
2026-10-06 00:00 11:01:19.97 -26:23:21.4 HIP 53963 30.17
2026-10-06 12:00 11:01:37.71 -26:26:00.0 HIP 53963 26.05
2026-10-07 00:00 11:01:55.41 -26:28:38.8 HIP 53963 22.19
2026-10-07 12:00 11:02:13.06 -26:31:18.2 HIP 53963 18.74
2026-10-08 00:00 11:02:30.66 -26:33:57.9 HIP 53963 15.97
2026-10-08 12:00 11:02:48.21 -26:36:38.0 HIP 53963 14.27
2026-10-09 00:00 11:03:05.71 -26:39:18.5 HIP 53963 14.02
2026-10-09 12:00 11:03:23.16 -26:41:59.4 HIP 53963 15.30
2026-10-10 00:00 11:03:40.55 -26:44:40.7 HIP 54167 16.35
2026-10-10 12:00 11:03:57.90 -26:47:22.4 HIP 54167 11.85
2026-10-11 00:00 11:04:15.18 -26:50:04.4 HIP 54167 7.63