| 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
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) |
| 2026-07-29 00:00 |
05:37:11.92 |
+32:29:19.6 |
HIP 26544 |
18.94 |
| 2026-07-29 12:00 |
05:37:14.71 |
+32:29:25.6 |
HIP 26544 |
18.36 |
| 2026-07-30 00:00 |
05:37:17.48 |
+32:29:31.8 |
HIP 26544 |
17.78 |
| 2026-07-30 12:00 |
05:37:20.23 |
+32:29:37.9 |
HIP 26544 |
17.21 |
| 2026-07-31 00:00 |
05:37:22.96 |
+32:29:44.1 |
HIP 26544 |
16.64 |
| 2026-07-31 12:00 |
05:37:25.68 |
+32:29:50.3 |
HIP 26544 |
16.08 |
| 2026-08-01 00:00 |
05:37:28.37 |
+32:29:56.5 |
HIP 26544 |
15.52 |
| 2026-08-01 12:00 |
05:37:31.04 |
+32:30:02.8 |
HIP 26544 |
14.97 |
| 2026-08-02 00:00 |
05:37:33.70 |
+32:30:09.1 |
HIP 26544 |
14.43 |
| 2026-08-02 12:00 |
05:37:36.33 |
+32:30:15.4 |
HIP 26544 |
13.89 |
| 2026-08-03 00:00 |
05:37:38.94 |
+32:30:21.8 |
HIP 26544 |
13.36 |
| 2026-08-03 12:00 |
05:37:41.53 |
+32:30:28.2 |
HIP 26544 |
12.83 |
| 2026-08-04 00:00 |
05:37:44.10 |
+32:30:34.6 |
HIP 26544 |
12.31 |
| 2026-08-04 12:00 |
05:37:46.65 |
+32:30:41.1 |
HIP 26544 |
11.80 |
| 2026-08-05 00:00 |
05:37:49.17 |
+32:30:47.6 |
HIP 26544 |
11.30 |
| 2026-08-05 12:00 |
05:37:51.68 |
+32:30:54.1 |
HIP 26544 |
10.81 |
| 2026-08-06 00:00 |
05:37:54.16 |
+32:31:00.6 |
HIP 26544 |
10.32 |
| 2026-08-06 12:00 |
05:37:56.62 |
+32:31:07.2 |
HIP 26544 |
9.85 |
| 2026-08-07 00:00 |
05:37:59.06 |
+32:31:13.8 |
HIP 26544 |
9.38 |
| 2026-08-07 12:00 |
05:38:01.48 |
+32:31:20.4 |
HIP 26544 |
8.93 |
| 2026-08-08 00:00 |
05:38:03.88 |
+32:31:27.1 |
HIP 26544 |
8.49 |
| 2026-08-08 12:00 |
05:38:06.25 |
+32:31:33.8 |
HIP 26544 |
8.07 |
| 2026-08-09 00:00 |
05:38:08.60 |
+32:31:40.5 |
HIP 26544 |
7.66 |
| 2026-08-09 12:00 |
05:38:10.93 |
+32:31:47.2 |
HIP 26544 |
7.26 |
| 2026-08-10 00:00 |
05:38:13.23 |
+32:31:54.0 |
HIP 26544 |
6.89 |
| 2026-08-10 12:00 |
05:38:15.51 |
+32:32:00.8 |
HIP 26544 |
6.53 |
| 2026-08-11 00:00 |
05:38:17.76 |
+32:32:07.6 |
HIP 26544 |
6.20 |
| 2026-08-11 12:00 |
05:38:20.00 |
+32:32:14.4 |
HIP 26544 |
5.90 |
| 2026-08-12 00:00 |
05:38:22.21 |
+32:32:21.3 |
HIP 26544 |
5.62 |
| 2026-08-12 12:00 |
05:38:24.39 |
+32:32:28.2 |
HIP 26544 |
5.38 |
| 2026-08-13 00:00 |
05:38:26.55 |
+32:32:35.1 |
HIP 26544 |
5.17 |
| 2026-08-13 12:00 |
05:38:28.69 |
+32:32:42.0 |
HIP 26544 |
5.01 |
| 2026-08-14 00:00 |
05:38:30.80 |
+32:32:49.0 |
HIP 26544 |
4.88 |
| 2026-08-14 12:00 |
05:38:32.88 |
+32:32:56.0 |
HIP 26544 |
4.80 |
| 2026-08-15 00:00 |
05:38:34.94 |
+32:33:03.0 |
HIP 26544 |
4.76 |
| 2026-08-15 12:00 |
05:38:36.98 |
+32:33:10.0 |
HIP 26544 |
4.76 |
| 2026-08-16 00:00 |
05:38:38.99 |
+32:33:17.1 |
HIP 26544 |
4.81 |
| 2026-08-16 12:00 |
05:38:40.98 |
+32:33:24.1 |
HIP 26544 |
4.90 |
| 2026-08-17 00:00 |
05:38:42.94 |
+32:33:31.2 |
HIP 26544 |
5.02 |
| 2026-08-17 12:00 |
05:38:44.87 |
+32:33:38.3 |
HIP 26544 |
5.18 |
| 2026-08-18 00:00 |
05:38:46.78 |
+32:33:45.4 |
HIP 26544 |
5.36 |
| 2026-08-18 12:00 |
05:38:48.66 |
+32:33:52.6 |
HIP 26544 |
5.57 |
| 2026-08-19 00:00 |
05:38:50.52 |
+32:33:59.8 |
HIP 26544 |
5.80 |