| Parameter |
Value |
| Designation |
C/2006 U6 (Spacewatch) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2008-06-05T11:25:18.736320Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:01Z |
| Obs used |
552 |
| NEO |
- |
| M1 |
10.900 |
| K1 |
5.750 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2008-04-03.0000000 |
| e |
0.99870621 |
| q (au) |
2.498397 |
| a (au) |
1931.066467 |
| i (deg) |
84.878944 |
| Ω (om, deg) |
180.186317 |
| ω (w, deg) |
276.596980 |
| M (ma, deg) |
359.999263 |
Magnitude
Scatter + Global Linear
$$
M_a = (13.450 + 2.405\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.450 |
| n |
2.405 |
| gf |
1.000 |
| gb |
-0.706 |
| 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 |
| 2006-09-15 |
2007-09-14 |
+2.5893 |
-1.956 |
| 2007-09-14 |
2008-05-08 |
-3.2129 |
+1.746 |
| 2008-06-11 |
2010-06-04 |
-0.0917 |
-0.202 |
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 |
15:16:35.74 |
+54:18:49.1 |
HIP 74610 |
17.67 |
| 2026-03-26 12:00 |
15:16:32.26 |
+54:19:28.4 |
HIP 74610 |
16.98 |
| 2026-03-27 00:00 |
15:16:28.74 |
+54:20:07.4 |
HIP 74610 |
16.30 |
| 2026-03-27 12:00 |
15:16:25.18 |
+54:20:46.2 |
HIP 74610 |
15.62 |
| 2026-03-28 00:00 |
15:16:21.59 |
+54:21:24.6 |
HIP 74610 |
14.96 |
| 2026-03-28 12:00 |
15:16:17.96 |
+54:22:02.8 |
HIP 74610 |
14.32 |
| 2026-03-29 00:00 |
15:16:14.30 |
+54:22:40.7 |
HIP 74610 |
13.68 |
| 2026-03-29 12:00 |
15:16:10.61 |
+54:23:18.3 |
HIP 74610 |
13.07 |
| 2026-03-30 00:00 |
15:16:06.88 |
+54:23:55.7 |
HIP 74610 |
12.48 |
| 2026-03-30 12:00 |
15:16:03.12 |
+54:24:32.7 |
HIP 74610 |
11.90 |
| 2026-03-31 00:00 |
15:15:59.33 |
+54:25:09.4 |
HIP 74610 |
11.36 |
| 2026-03-31 12:00 |
15:15:55.50 |
+54:25:45.9 |
HIP 74610 |
10.85 |
| 2026-04-01 00:00 |
15:15:51.64 |
+54:26:22.0 |
HIP 74610 |
10.37 |
| 2026-04-01 12:00 |
15:15:47.75 |
+54:26:57.9 |
HIP 74610 |
9.93 |
| 2026-04-02 00:00 |
15:15:43.82 |
+54:27:33.4 |
HIP 74610 |
9.53 |
| 2026-04-02 12:00 |
15:15:39.87 |
+54:28:08.7 |
HIP 74610 |
9.19 |
| 2026-04-03 00:00 |
15:15:35.88 |
+54:28:43.6 |
HIP 74610 |
8.90 |
| 2026-04-03 12:00 |
15:15:31.87 |
+54:29:18.2 |
HIP 74610 |
8.68 |
| 2026-04-04 00:00 |
15:15:27.82 |
+54:29:52.5 |
HIP 74610 |
8.52 |
| 2026-04-04 12:00 |
15:15:23.74 |
+54:30:26.5 |
HIP 74610 |
8.43 |
| 2026-04-05 00:00 |
15:15:19.63 |
+54:31:00.2 |
HIP 74610 |
8.42 |
| 2026-04-05 12:00 |
15:15:15.49 |
+54:31:33.6 |
HIP 74610 |
8.48 |
| 2026-04-06 00:00 |
15:15:11.33 |
+54:32:06.6 |
HIP 74610 |
8.61 |
| 2026-04-06 12:00 |
15:15:07.13 |
+54:32:39.3 |
HIP 74610 |
8.81 |
| 2026-04-07 00:00 |
15:15:02.91 |
+54:33:11.7 |
HIP 74610 |
9.07 |
| 2026-04-07 12:00 |
15:14:58.66 |
+54:33:43.8 |
HIP 74610 |
9.39 |
| 2026-04-08 00:00 |
15:14:54.38 |
+54:34:15.5 |
HIP 74610 |
9.76 |
| 2026-04-08 12:00 |
15:14:50.07 |
+54:34:46.9 |
HIP 74610 |
10.17 |
| 2026-04-09 00:00 |
15:14:45.73 |
+54:35:17.9 |
HIP 74610 |
10.63 |
| 2026-04-09 12:00 |
15:14:41.37 |
+54:35:48.6 |
HIP 74610 |
11.12 |
| 2026-04-10 00:00 |
15:14:36.98 |
+54:36:19.0 |
HIP 74610 |
11.64 |
| 2026-04-10 12:00 |
15:14:32.57 |
+54:36:49.0 |
HIP 74610 |
12.19 |
| 2026-04-11 00:00 |
15:14:28.13 |
+54:37:18.7 |
HIP 74610 |
12.77 |
| 2026-04-11 12:00 |
15:14:23.66 |
+54:37:48.1 |
HIP 74610 |
13.36 |
| 2026-04-12 00:00 |
15:14:19.17 |
+54:38:17.0 |
HIP 74610 |
13.97 |
| 2026-04-12 12:00 |
15:14:14.66 |
+54:38:45.7 |
HIP 74610 |
14.59 |
| 2026-04-13 00:00 |
15:14:10.12 |
+54:39:13.9 |
HIP 74610 |
15.23 |
| 2026-04-13 12:00 |
15:14:05.56 |
+54:39:41.9 |
HIP 74610 |
15.88 |
| 2026-04-14 00:00 |
15:14:00.97 |
+54:40:09.4 |
HIP 74610 |
16.54 |
| 2026-04-14 12:00 |
15:13:56.36 |
+54:40:36.6 |
HIP 74610 |
17.20 |
| 2026-04-15 00:00 |
15:13:51.73 |
+54:41:03.5 |
HIP 74610 |
17.88 |
| 2026-04-15 12:00 |
15:13:47.08 |
+54:41:29.9 |
HIP 74610 |
18.56 |
| 2026-04-16 00:00 |
15:13:42.40 |
+54:41:56.0 |
HIP 74610 |
19.24 |