| Parameter |
Value |
| Designation |
C/2009 W2 (Boattini) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2010-05-01T16:06:03.297600Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:37Z |
| Obs used |
93 |
| NEO |
- |
| M1 |
6.900 |
| K1 |
10.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2009-12-12.0000000 |
| e |
0.99955388 |
| q (au) |
6.907134 |
| a (au) |
15482.794125 |
| i (deg) |
164.490524 |
| Ω (om, deg) |
199.580074 |
| ω (w, deg) |
121.325958 |
| M (ma, deg) |
359.999928 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.856 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.856 |
| n |
6.000 |
| gf |
0.991 |
| gb |
-0.810 |
| k |
0.831 |
| δ90 |
7.006 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
21:39:45.86 |
-28:59:36.5 |
HIP 107023 |
17.43 |
| 2026-06-01 12:00 |
21:39:44.09 |
-28:59:59.8 |
HIP 107023 |
17.34 |
| 2026-06-02 00:00 |
21:39:42.27 |
-29:00:23.2 |
HIP 107023 |
17.27 |
| 2026-06-02 12:00 |
21:39:40.43 |
-29:00:46.7 |
HIP 107023 |
17.23 |
| 2026-06-03 00:00 |
21:39:38.54 |
-29:01:10.3 |
HIP 107023 |
17.21 |
| 2026-06-03 12:00 |
21:39:36.63 |
-29:01:34.1 |
HIP 107023 |
17.20 |
| 2026-06-04 00:00 |
21:39:34.68 |
-29:01:57.9 |
HIP 107023 |
17.23 |
| 2026-06-04 12:00 |
21:39:32.69 |
-29:02:21.9 |
HIP 107023 |
17.27 |
| 2026-06-05 00:00 |
21:39:30.67 |
-29:02:46.0 |
HIP 107023 |
17.34 |
| 2026-06-05 12:00 |
21:39:28.62 |
-29:03:10.1 |
HIP 107023 |
17.44 |
| 2026-06-06 00:00 |
21:39:26.53 |
-29:03:34.4 |
HIP 107023 |
17.56 |
| 2026-06-06 12:00 |
21:39:24.41 |
-29:03:58.8 |
HIP 107023 |
17.71 |
| 2026-06-07 00:00 |
21:39:22.26 |
-29:04:23.3 |
HIP 107023 |
17.88 |
| 2026-06-07 12:00 |
21:39:20.07 |
-29:04:47.8 |
HIP 107023 |
18.08 |
| 2026-06-08 00:00 |
21:39:17.84 |
-29:05:12.5 |
HIP 107023 |
18.30 |
| 2026-06-08 12:00 |
21:39:15.59 |
-29:05:37.3 |
HIP 107023 |
18.54 |
| 2026-06-09 00:00 |
21:39:13.30 |
-29:06:02.2 |
HIP 107023 |
18.82 |
| 2026-06-09 12:00 |
21:39:10.97 |
-29:06:27.1 |
HIP 107023 |
19.11 |
| 2026-06-10 00:00 |
21:39:08.61 |
-29:06:52.2 |
HIP 107023 |
19.43 |
| 2026-06-10 12:00 |
21:39:06.22 |
-29:07:17.3 |
HIP 107023 |
19.78 |
| 2026-06-11 00:00 |
21:39:03.80 |
-29:07:42.5 |
HIP 107023 |
20.14 |
| 2026-06-11 12:00 |
21:39:01.34 |
-29:08:07.8 |
HIP 107023 |
20.53 |
| 2026-06-12 00:00 |
21:38:58.85 |
-29:08:33.2 |
HIP 107023 |
20.94 |
| 2026-06-12 12:00 |
21:38:56.33 |
-29:08:58.7 |
HIP 107023 |
21.37 |
| 2026-06-13 00:00 |
21:38:53.77 |
-29:09:24.3 |
HIP 107023 |
21.82 |
| 2026-06-13 12:00 |
21:38:51.18 |
-29:09:49.9 |
HIP 107023 |
22.29 |
| 2026-06-14 00:00 |
21:38:48.56 |
-29:10:15.6 |
HIP 107023 |
22.78 |
| 2026-06-14 12:00 |
21:38:45.91 |
-29:10:41.4 |
HIP 107023 |
23.29 |
| 2026-06-15 00:00 |
21:38:43.22 |
-29:11:07.3 |
HIP 107023 |
23.82 |
| 2026-06-15 12:00 |
21:38:40.50 |
-29:11:33.2 |
HIP 107023 |
24.36 |
| 2026-06-16 00:00 |
21:38:37.75 |
-29:11:59.3 |
HIP 107023 |
24.92 |
| 2026-06-16 12:00 |
21:38:34.97 |
-29:12:25.3 |
HIP 107023 |
25.50 |
| 2026-06-17 00:00 |
21:38:32.16 |
-29:12:51.5 |
HIP 106840 |
25.63 |
| 2026-06-17 12:00 |
21:38:29.31 |
-29:13:17.7 |
HIP 106840 |
25.16 |
| 2026-06-18 00:00 |
21:38:26.43 |
-29:13:43.9 |
HIP 106840 |
24.70 |
| 2026-06-18 12:00 |
21:38:23.53 |
-29:14:10.3 |
HIP 106840 |
24.26 |
| 2026-06-19 00:00 |
21:38:20.59 |
-29:14:36.6 |
HIP 106840 |
23.83 |
| 2026-06-19 12:00 |
21:38:17.62 |
-29:15:03.1 |
HIP 106840 |
23.42 |
| 2026-06-20 00:00 |
21:38:14.62 |
-29:15:29.6 |
HIP 106840 |
23.03 |
| 2026-06-20 12:00 |
21:38:11.59 |
-29:15:56.1 |
HIP 106840 |
22.66 |
| 2026-06-21 00:00 |
21:38:08.53 |
-29:16:22.7 |
HIP 106840 |
22.32 |
| 2026-06-21 12:00 |
21:38:05.44 |
-29:16:49.3 |
HIP 106840 |
21.99 |
| 2026-06-22 00:00 |
21:38:02.32 |
-29:17:16.0 |
HIP 106840 |
21.69 |