| Parameter |
Value |
| Designation |
C/2006 W3 (Christensen) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2009-07-06T15:35:19.720320Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:02Z |
| Obs used |
5639 |
| NEO |
- |
| M1 |
8.200 |
| K1 |
5.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2009-03-11.0000000 |
| e |
0.99982443 |
| q (au) |
3.126233 |
| a (au) |
17806.222961 |
| i (deg) |
127.074694 |
| Ω (om, deg) |
113.570597 |
| ω (w, deg) |
133.514480 |
| M (ma, deg) |
359.999951 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.022 + 3.691\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.022 |
| n |
3.691 |
| gf |
1.000 |
| gb |
-0.517 |
| k |
0.800 |
| 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 |
| 2006-10-29 |
2009-07-06 |
+3.5691 |
-2.737 |
| 2009-07-06 |
2011-09-24 |
+0.7709 |
-1.054 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
10:37:16.73 |
-51:19:57.7 |
HIP 51868 |
14.56 |
| 2026-03-26 12:00 |
10:37:11.75 |
-51:19:24.9 |
HIP 51868 |
14.09 |
| 2026-03-27 00:00 |
10:37:06.79 |
-51:18:51.7 |
HIP 51868 |
13.67 |
| 2026-03-27 12:00 |
10:37:01.85 |
-51:18:18.1 |
HIP 51868 |
13.32 |
| 2026-03-28 00:00 |
10:36:56.94 |
-51:17:44.3 |
HIP 51868 |
13.02 |
| 2026-03-28 12:00 |
10:36:52.06 |
-51:17:10.2 |
HIP 51868 |
12.80 |
| 2026-03-29 00:00 |
10:36:47.20 |
-51:16:35.7 |
HIP 51868 |
12.66 |
| 2026-03-29 12:00 |
10:36:42.37 |
-51:16:00.9 |
HIP 51868 |
12.59 |
| 2026-03-30 00:00 |
10:36:37.56 |
-51:15:25.9 |
HIP 51868 |
12.59 |
| 2026-03-30 12:00 |
10:36:32.78 |
-51:14:50.5 |
HIP 51868 |
12.68 |
| 2026-03-31 00:00 |
10:36:28.02 |
-51:14:14.8 |
HIP 51868 |
12.84 |
| 2026-03-31 12:00 |
10:36:23.29 |
-51:13:38.9 |
HIP 51868 |
13.08 |
| 2026-04-01 00:00 |
10:36:18.59 |
-51:13:02.6 |
HIP 51868 |
13.38 |
| 2026-04-01 12:00 |
10:36:13.92 |
-51:12:26.1 |
HIP 51868 |
13.75 |
| 2026-04-02 00:00 |
10:36:09.27 |
-51:11:49.2 |
HIP 51868 |
14.18 |
| 2026-04-02 12:00 |
10:36:04.66 |
-51:11:12.1 |
HIP 51868 |
14.66 |
| 2026-04-03 00:00 |
10:36:00.07 |
-51:10:34.7 |
HIP 51868 |
15.20 |
| 2026-04-03 12:00 |
10:35:55.51 |
-51:09:57.0 |
HIP 51868 |
15.77 |
| 2026-04-04 00:00 |
10:35:50.98 |
-51:09:19.1 |
HIP 51868 |
16.39 |
| 2026-04-04 12:00 |
10:35:46.48 |
-51:08:40.8 |
HIP 51868 |
17.04 |
| 2026-04-05 00:00 |
10:35:42.01 |
-51:08:02.4 |
HIP 51702 |
17.60 |
| 2026-04-05 12:00 |
10:35:37.57 |
-51:07:23.6 |
HIP 51702 |
16.84 |
| 2026-04-06 00:00 |
10:35:33.15 |
-51:06:44.6 |
HIP 51702 |
16.10 |
| 2026-04-06 12:00 |
10:35:28.77 |
-51:06:05.3 |
HIP 51702 |
15.39 |
| 2026-04-07 00:00 |
10:35:24.43 |
-51:05:25.7 |
HIP 51702 |
14.72 |
| 2026-04-07 12:00 |
10:35:20.11 |
-51:04:45.9 |
HIP 51702 |
14.07 |
| 2026-04-08 00:00 |
10:35:15.82 |
-51:04:05.9 |
HIP 51702 |
13.47 |
| 2026-04-08 12:00 |
10:35:11.57 |
-51:03:25.6 |
HIP 51702 |
12.92 |
| 2026-04-09 00:00 |
10:35:07.34 |
-51:02:45.0 |
HIP 51702 |
12.42 |
| 2026-04-09 12:00 |
10:35:03.15 |
-51:02:04.2 |
HIP 51702 |
11.98 |
| 2026-04-10 00:00 |
10:34:59.00 |
-51:01:23.2 |
HIP 51702 |
11.61 |
| 2026-04-10 12:00 |
10:34:54.87 |
-51:00:42.0 |
HIP 51702 |
11.31 |
| 2026-04-11 00:00 |
10:34:50.78 |
-51:00:00.5 |
HIP 51702 |
11.08 |
| 2026-04-11 12:00 |
10:34:46.72 |
-50:59:18.7 |
HIP 51702 |
10.95 |
| 2026-04-12 00:00 |
10:34:42.70 |
-50:58:36.8 |
HIP 51702 |
10.89 |
| 2026-04-12 12:00 |
10:34:38.71 |
-50:57:54.6 |
HIP 51702 |
10.93 |
| 2026-04-13 00:00 |
10:34:34.76 |
-50:57:12.2 |
HIP 51702 |
11.05 |
| 2026-04-13 12:00 |
10:34:30.84 |
-50:56:29.6 |
HIP 51702 |
11.26 |
| 2026-04-14 00:00 |
10:34:26.95 |
-50:55:46.8 |
HIP 51702 |
11.54 |
| 2026-04-14 12:00 |
10:34:23.10 |
-50:55:03.7 |
HIP 51702 |
11.90 |
| 2026-04-15 00:00 |
10:34:19.29 |
-50:54:20.5 |
HIP 51702 |
12.33 |
| 2026-04-15 12:00 |
10:34:15.51 |
-50:53:37.0 |
HIP 51702 |
12.81 |
| 2026-04-16 00:00 |
10:34:11.77 |
-50:52:53.4 |
HIP 51702 |
13.35 |