C/2007 W1 (Boattini)

Metadata

Parameter Value
Designation C/2007 W1 (Boattini)
Type C
Perihelion (tp_cal, UTC) 2008-06-24T21:18:35.372160Z
Orbit solution date (soln_date, UTC) 2022-06-10T02:47:51Z
Obs used 1639
NEO -
M1 15.000
K1 8.250
PC -
Osculating Elements
Parameter Value
Epoch (epoch_cal, TDB) 2008-05-25.0000000
e 1.00010076
q (au) 0.849660
a (au) -8432.181012
i (deg) 9.888931
Ω (om, deg) 334.529078
ω (w, deg) 306.550768
M (ma, deg) -0.000039

Magnitude

C/2007 W1 (Boattini) · Magnitude (Full range)

Scatter + Global Linear

$$ M_a = (14.072 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

Model Parameters

Parameter Value
H0 14.072
n 2.000
gf 1.000
gb -0.660
k 0.968
δ90 9.995
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
2007-03-21 2008-06-24 +5.8954 -3.412
2008-06-26 2008-12-17 +14.2002 -2.793

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 05:28:14.95 +32:22:51.9 HIP 25590 8.88
2026-05-12 12:00 05:28:18.14 +32:22:50.1 HIP 25590 9.02
2026-05-13 00:00 05:28:21.34 +32:22:48.5 HIP 25590 9.21
2026-05-13 12:00 05:28:24.56 +32:22:46.8 HIP 25590 9.44
2026-05-14 00:00 05:28:27.79 +32:22:45.3 HIP 25590 9.72
2026-05-14 12:00 05:28:31.03 +32:22:43.8 HIP 25590 10.04
2026-05-15 00:00 05:28:34.29 +32:22:42.3 HIP 25590 10.39
2026-05-15 12:00 05:28:37.57 +32:22:40.9 HIP 25590 10.78
2026-05-16 00:00 05:28:40.85 +32:22:39.6 HIP 25590 11.19
2026-05-16 12:00 05:28:44.15 +32:22:38.4 HIP 25590 11.63
2026-05-17 00:00 05:28:47.47 +32:22:37.2 HIP 25590 12.10
2026-05-17 12:00 05:28:50.79 +32:22:36.0 HIP 25696 11.95
2026-05-18 00:00 05:28:54.13 +32:22:34.9 HIP 25696 11.63
2026-05-18 12:00 05:28:57.48 +32:22:33.9 HIP 25696 11.34
2026-05-19 00:00 05:29:00.85 +32:22:32.9 HIP 25696 11.09
2026-05-19 12:00 05:29:04.22 +32:22:32.0 HIP 25696 10.88
2026-05-20 00:00 05:29:07.61 +32:22:31.2 HIP 25696 10.72
2026-05-20 12:00 05:29:11.01 +32:22:30.4 HIP 25696 10.60
2026-05-21 00:00 05:29:14.42 +32:22:29.6 HIP 25696 10.53
2026-05-21 12:00 05:29:17.84 +32:22:29.0 HIP 25696 10.51
2026-05-22 00:00 05:29:21.27 +32:22:28.4 HIP 25696 10.54
2026-05-22 12:00 05:29:24.71 +32:22:27.8 HIP 25696 10.62
2026-05-23 00:00 05:29:28.17 +32:22:27.3 HIP 25696 10.76
2026-05-23 12:00 05:29:31.63 +32:22:26.9 HIP 25696 10.94
2026-05-24 00:00 05:29:35.10 +32:22:26.5 HIP 25696 11.17
2026-05-24 12:00 05:29:38.59 +32:22:26.2 HIP 25696 11.44
2026-05-25 00:00 05:29:42.08 +32:22:25.9 HIP 25696 11.75
2026-05-25 12:00 05:29:45.58 +32:22:25.7 HIP 25696 12.10
2026-05-26 00:00 05:29:49.09 +32:22:25.6 HIP 25696 12.49
2026-05-26 12:00 05:29:52.61 +32:22:25.5 HIP 25696 12.91
2026-05-27 00:00 05:29:56.13 +32:22:25.4 HIP 25696 13.36
2026-05-27 12:00 05:29:59.67 +32:22:25.5 HIP 25696 13.84
2026-05-28 00:00 05:30:03.21 +32:22:25.5 HIP 25696 14.35
2026-05-28 12:00 05:30:06.76 +32:22:25.7 HIP 25696 14.87
2026-05-29 00:00 05:30:10.32 +32:22:25.9 HIP 25696 15.42
2026-05-29 12:00 05:30:13.89 +32:22:26.2 HIP 25696 15.98
2026-05-30 00:00 05:30:17.46 +32:22:26.5 HIP 25696 16.57
2026-05-30 12:00 05:30:21.04 +32:22:26.8 HIP 25696 17.16
2026-05-31 00:00 05:30:24.62 +32:22:27.3 HIP 25696 17.77
2026-05-31 12:00 05:30:28.22 +32:22:27.8 HIP 25876 17.23
2026-06-01 00:00 05:30:31.82 +32:22:28.3 HIP 25876 16.70
2026-06-01 12:00 05:30:35.42 +32:22:28.9 HIP 25876 16.19
2026-06-02 00:00 05:30:39.03 +32:22:29.6 HIP 25876 15.70