P/2009 Y2 (Kowalski)
| Parameter |
Value |
| Designation |
P/2009 Y2 (Kowalski) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2010-03-30T16:39:00.302400Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:38Z |
| Obs used |
178 |
| NEO |
- |
| M1 |
6.200 |
| K1 |
28.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2010-01-11.0000000 |
| e |
0.64052556 |
| q (au) |
2.339193 |
| a (au) |
6.507258 |
| i (deg) |
29.929609 |
| Ω (om, deg) |
262.126517 |
| ω (w, deg) |
171.961934 |
| M (ma, deg) |
355.327521 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.523 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.523 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.502 |
| k |
1.000 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
22:23:45.92 |
+16:25:22.9 |
HIP 110493 |
13.17 |
| 2026-02-03 12:00 |
22:24:25.16 |
+16:27:49.4 |
HIP 110600 |
12.04 |
| 2026-02-04 00:00 |
22:25:04.49 |
+16:30:17.3 |
HIP 110600 |
17.33 |
| 2026-02-04 12:00 |
22:25:43.90 |
+16:32:46.7 |
HIP 110600 |
25.45 |
| 2026-02-05 00:00 |
22:26:23.39 |
+16:35:17.4 |
HIP 110623 |
31.43 |
| 2026-02-05 12:00 |
22:27:02.97 |
+16:37:49.5 |
HIP 110833 |
27.02 |
| 2026-02-06 00:00 |
22:27:42.63 |
+16:40:23.1 |
HIP 110833 |
25.05 |
| 2026-02-06 12:00 |
22:28:22.38 |
+16:42:58.0 |
HIP 110957 |
25.75 |
| 2026-02-07 00:00 |
22:29:02.20 |
+16:45:34.2 |
HIP 111092 |
20.49 |
| 2026-02-07 12:00 |
22:29:42.11 |
+16:48:11.9 |
HIP 111092 |
10.73 |
| 2026-02-08 00:00 |
22:30:22.10 |
+16:50:50.9 |
HIP 111092 |
2.56 |
| 2026-02-08 12:00 |
22:31:02.18 |
+16:53:31.3 |
HIP 111092 |
9.77 |
| 2026-02-09 00:00 |
22:31:42.33 |
+16:56:13.0 |
HIP 111092 |
19.58 |
| 2026-02-09 12:00 |
22:32:22.56 |
+16:58:56.1 |
HIP 111410 |
29.43 |
| 2026-02-10 00:00 |
22:33:02.87 |
+17:01:40.5 |
HIP 111410 |
19.46 |
| 2026-02-10 12:00 |
22:33:43.27 |
+17:04:26.3 |
HIP 111410 |
9.57 |
| 2026-02-11 00:00 |
22:34:23.74 |
+17:07:13.4 |
HIP 111410 |
2.42 |
| 2026-02-11 12:00 |
22:35:04.29 |
+17:10:01.8 |
HIP 111410 |
11.09 |
| 2026-02-12 00:00 |
22:35:44.91 |
+17:12:51.6 |
HIP 111658 |
20.78 |
| 2026-02-12 12:00 |
22:36:25.62 |
+17:15:42.7 |
HIP 111658 |
10.73 |
| 2026-02-13 00:00 |
22:37:06.40 |
+17:18:35.1 |
HIP 111658 |
1.86 |
| 2026-02-13 12:00 |
22:37:47.26 |
+17:21:28.8 |
HIP 111658 |
9.92 |
| 2026-02-14 00:00 |
22:38:28.20 |
+17:24:23.9 |
HIP 111823 |
19.71 |
| 2026-02-14 12:00 |
22:39:09.21 |
+17:27:20.2 |
HIP 111845 |
14.60 |
| 2026-02-15 00:00 |
22:39:50.30 |
+17:30:17.8 |
HIP 111845 |
14.05 |
| 2026-02-15 12:00 |
22:40:31.47 |
+17:33:16.7 |
HIP 111845 |
19.78 |
| 2026-02-16 00:00 |
22:41:12.70 |
+17:36:16.9 |
HIP 112120 |
20.69 |
| 2026-02-16 12:00 |
22:41:54.02 |
+17:39:18.3 |
HIP 112120 |
10.52 |
| 2026-02-17 00:00 |
22:42:35.40 |
+17:42:21.0 |
HIP 112120 |
2.36 |
| 2026-02-17 12:00 |
22:43:16.86 |
+17:45:25.0 |
HIP 112120 |
10.67 |
| 2026-02-18 00:00 |
22:43:58.39 |
+17:48:30.2 |
HIP 112268 |
16.36 |
| 2026-02-18 12:00 |
22:44:40.00 |
+17:51:36.7 |
HIP 112306 |
15.64 |
| 2026-02-19 00:00 |
22:45:21.67 |
+17:54:44.4 |
HIP 112306 |
13.93 |
| 2026-02-19 12:00 |
22:46:03.42 |
+17:57:53.4 |
HIP 112306 |
18.96 |
| 2026-02-20 00:00 |
22:46:45.23 |
+18:01:03.5 |
HIP 112506 |
15.05 |
| 2026-02-20 12:00 |
22:47:27.12 |
+18:04:14.9 |
HIP 112506 |
15.51 |
| 2026-02-21 00:00 |
22:48:09.08 |
+18:07:27.5 |
HIP 112496 |
20.44 |
| 2026-02-21 12:00 |
22:48:51.11 |
+18:10:41.3 |
HIP 112765 |
19.64 |
| 2026-02-22 00:00 |
22:49:33.20 |
+18:13:56.3 |
HIP 112765 |
10.47 |
| 2026-02-22 12:00 |
22:50:15.36 |
+18:17:12.5 |
HIP 112765 |
7.40 |
| 2026-02-23 00:00 |
22:50:57.60 |
+18:20:29.8 |
HIP 112868 |
14.68 |
| 2026-02-23 12:00 |
22:51:39.89 |
+18:23:48.3 |
HIP 112868 |
17.14 |
| 2026-02-24 00:00 |
22:52:22.26 |
+18:27:08.0 |
HIP 112868 |
24.43 |