C/2006 Q1 (McNaught)

Metadata

Parameter Value
Designation C/2006 Q1 (McNaught)
Type C
Perihelion (tp_cal, UTC) 2008-07-03T20:33:15.033600Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:31:00Z
Obs used 2710
NEO -
M1 9.300
K1 4.750
PC -
Osculating Elements
Parameter Value
Epoch (epoch_cal, TDB) 2009-02-17.0000000
e 0.99960042
q (au) 2.763713
a (au) 6916.474116
i (deg) 59.050363
Ω (om, deg) 199.547074
ω (w, deg) 344.381853
M (ma, deg) 0.000391

Magnitude

C/2006 Q1 (McNaught) · Magnitude (Full range)

Scatter + Global Linear

$$ M_a = (10.125 + 2.335\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

Model Parameters

Parameter Value
H0 10.125
n 2.335
gf 0.943
gb -0.656
k 0.906
δ90 6.533
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
2006-08-20 2008-01-29 +0.9412 -1.227
2008-01-29 2008-07-01 -6.8432 +2.139
2008-07-03 2009-07-06 +2.3103 -1.470
2009-07-06 2010-10-17 +3.1514 -2.364

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 22:21:39.98 +32:09:19.0 HIP 110526 29.39
2026-05-12 12:00 22:21:41.00 +32:09:52.6 HIP 110526 28.88
2026-05-13 00:00 22:21:41.99 +32:10:26.2 HIP 110526 28.37
2026-05-13 12:00 22:21:42.95 +32:10:59.8 HIP 110526 27.87
2026-05-14 00:00 22:21:43.89 +32:11:33.3 HIP 110526 27.38
2026-05-14 12:00 22:21:44.79 +32:12:06.7 HIP 110526 26.90
2026-05-15 00:00 22:21:45.66 +32:12:40.1 HIP 110526 26.43
2026-05-15 12:00 22:21:46.51 +32:13:13.4 HIP 110526 25.97
2026-05-16 00:00 22:21:47.32 +32:13:46.7 HIP 110526 25.52
2026-05-16 12:00 22:21:48.11 +32:14:19.9 HIP 110526 25.09
2026-05-17 00:00 22:21:48.86 +32:14:53.1 HIP 110526 24.66
2026-05-17 12:00 22:21:49.58 +32:15:26.2 HIP 110526 24.25
2026-05-18 00:00 22:21:50.28 +32:15:59.2 HIP 110526 23.85
2026-05-18 12:00 22:21:50.94 +32:16:32.1 HIP 110526 23.46
2026-05-19 00:00 22:21:51.58 +32:17:05.0 HIP 110526 23.09
2026-05-19 12:00 22:21:52.18 +32:17:37.8 HIP 110526 22.73
2026-05-20 00:00 22:21:52.76 +32:18:10.5 HIP 110526 22.38
2026-05-20 12:00 22:21:53.30 +32:18:43.2 HIP 110526 22.05
2026-05-21 00:00 22:21:53.81 +32:19:15.7 HIP 110526 21.74
2026-05-21 12:00 22:21:54.30 +32:19:48.2 HIP 110526 21.44
2026-05-22 00:00 22:21:54.75 +32:20:20.6 HIP 110526 21.16
2026-05-22 12:00 22:21:55.17 +32:20:52.9 HIP 110526 20.90
2026-05-23 00:00 22:21:55.57 +32:21:25.1 HIP 110526 20.65
2026-05-23 12:00 22:21:55.93 +32:21:57.2 HIP 110526 20.42
2026-05-24 00:00 22:21:56.26 +32:22:29.2 HIP 110526 20.21
2026-05-24 12:00 22:21:56.56 +32:23:01.2 HIP 110526 20.02
2026-05-25 00:00 22:21:56.84 +32:23:33.0 HIP 110526 19.85
2026-05-25 12:00 22:21:57.08 +32:24:04.7 HIP 110526 19.70
2026-05-26 00:00 22:21:57.29 +32:24:36.3 HIP 110526 19.57
2026-05-26 12:00 22:21:57.47 +32:25:07.8 HIP 110526 19.45
2026-05-27 00:00 22:21:57.62 +32:25:39.2 HIP 110526 19.36
2026-05-27 12:00 22:21:57.74 +32:26:10.5 HIP 110526 19.29
2026-05-28 00:00 22:21:57.83 +32:26:41.6 HIP 110526 19.24
2026-05-28 12:00 22:21:57.89 +32:27:12.7 HIP 110526 19.21
2026-05-29 00:00 22:21:57.92 +32:27:43.6 HIP 110526 19.20
2026-05-29 12:00 22:21:57.92 +32:28:14.4 HIP 110526 19.21
2026-05-30 00:00 22:21:57.89 +32:28:45.1 HIP 110526 19.23
2026-05-30 12:00 22:21:57.83 +32:29:15.7 HIP 110526 19.28
2026-05-31 00:00 22:21:57.74 +32:29:46.1 HIP 110526 19.35
2026-05-31 12:00 22:21:57.62 +32:30:16.4 HIP 110526 19.44
2026-06-01 00:00 22:21:57.47 +32:30:46.6 HIP 110526 19.55
2026-06-01 12:00 22:21:57.29 +32:31:16.6 HIP 110526 19.67
2026-06-02 00:00 22:21:57.08 +32:31:46.6 HIP 110526 19.81