C/2003 WT42 (LINEAR)

Metadata

Parameter Value
Designation C/2003 WT42 (LINEAR)
Type C
Perihelion (tp_cal, UTC) 2006-04-10T18:20:21.065280Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:30:36Z
Obs used 2466
NEO -
M1 6.200
K1 8.500
PC 0.030
Osculating Elements
Parameter Value
Epoch (epoch_cal, TDB) 2006-04-09.0000000
e 1.00258438
q (au) 5.190924
a (au) -2008.572797
i (deg) 31.410588
Ω (om, deg) 48.453889
ω (w, deg) 92.466923
M (ma, deg) -0.000019

Magnitude

C/2003 WT42 (LINEAR) · Magnitude (Full range)

Scatter + Global Linear

$$ M_a = (-0.750 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

Model Parameters

Parameter Value
H0 -0.750
n 6.000
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
2003-12-01 2006-04-02 -4.0705 +3.107
2006-04-17 2007-07-07 +16.4914 -11.805

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 18:16:32.72 -46:58:35.3 HIP 89578 4.34
2026-06-01 12:00 18:16:28.79 -46:58:45.7 HIP 89578 4.56
2026-06-02 00:00 18:16:24.84 -46:58:55.8 HIP 89578 4.88
2026-06-02 12:00 18:16:20.88 -46:59:05.8 HIP 89578 5.27
2026-06-03 00:00 18:16:16.90 -46:59:15.7 HIP 89578 5.73
2026-06-03 12:00 18:16:12.90 -46:59:25.4 HIP 89578 6.23
2026-06-04 00:00 18:16:08.89 -46:59:35.0 HIP 89578 6.78
2026-06-04 12:00 18:16:04.87 -46:59:44.4 HIP 89578 7.35
2026-06-05 00:00 18:16:00.83 -46:59:53.6 HIP 89578 7.95
2026-06-05 12:00 18:15:56.78 -47:00:02.7 HIP 89578 8.56
2026-06-06 00:00 18:15:52.71 -47:00:11.6 HIP 89578 9.20
2026-06-06 12:00 18:15:48.63 -47:00:20.4 HIP 89578 9.84
2026-06-07 00:00 18:15:44.53 -47:00:29.0 HIP 89578 10.50
2026-06-07 12:00 18:15:40.43 -47:00:37.4 HIP 89578 11.16
2026-06-08 00:00 18:15:36.31 -47:00:45.7 HIP 89578 11.84
2026-06-08 12:00 18:15:32.18 -47:00:53.8 HIP 89578 12.52
2026-06-09 00:00 18:15:28.04 -47:01:01.7 HIP 89578 13.20
2026-06-09 12:00 18:15:23.88 -47:01:09.5 HIP 89578 13.90
2026-06-10 00:00 18:15:19.72 -47:01:17.1 HIP 89578 14.59
2026-06-10 12:00 18:15:15.54 -47:01:24.6 HIP 89578 15.29
2026-06-11 00:00 18:15:11.35 -47:01:31.9 HIP 89578 16.00
2026-06-11 12:00 18:15:07.16 -47:01:39.0 HIP 89578 16.71
2026-06-12 00:00 18:15:02.95 -47:01:46.0 HIP 89578 17.42
2026-06-12 12:00 18:14:58.73 -47:01:52.7 HIP 89578 18.13
2026-06-13 00:00 18:14:54.51 -47:01:59.4 HIP 89578 18.85
2026-06-13 12:00 18:14:50.28 -47:02:05.8 HIP 89578 19.57
2026-06-14 00:00 18:14:46.04 -47:02:12.1 HIP 89578 20.29
2026-06-14 12:00 18:14:41.79 -47:02:18.2 HIP 89578 21.01
2026-06-15 00:00 18:14:37.53 -47:02:24.2 HIP 89578 21.74
2026-06-15 12:00 18:14:33.27 -47:02:29.9 HIP 89578 22.46
2026-06-16 00:00 18:14:29.00 -47:02:35.5 HIP 89578 23.19
2026-06-16 12:00 18:14:24.72 -47:02:41.0 HIP 89578 23.92
2026-06-17 00:00 18:14:20.44 -47:02:46.2 HIP 89578 24.65
2026-06-17 12:00 18:14:16.15 -47:02:51.3 HIP 89578 25.38
2026-06-18 00:00 18:14:11.86 -47:02:56.2 HIP 89578 26.11
2026-06-18 12:00 18:14:07.56 -47:03:01.0 HIP 89578 26.85
2026-06-19 00:00 18:14:03.26 -47:03:05.5 HIP 89578 27.58
2026-06-19 12:00 18:13:58.96 -47:03:09.9 HIP 89578 28.32
2026-06-20 00:00 18:13:54.65 -47:03:14.1 HIP 89578 29.05
2026-06-20 12:00 18:13:50.34 -47:03:18.2 HIP 89578 29.79
2026-06-21 00:00 18:13:46.03 -47:03:22.1 HIP 89578 30.52
2026-06-21 12:00 18:13:41.71 -47:03:25.8 HIP 89232 30.87
2026-06-22 00:00 18:13:37.39 -47:03:29.3 HIP 89064 30.63