| 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 |
0.991 |
| gb |
-0.502 |
| k |
1.000 |
| δ90 |
9.996 |
| 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) |
| 2026-07-29 00:00 |
03:14:49.07 |
+40:24:23.1 |
HIP 15059 |
11.21 |
| 2026-07-29 12:00 |
03:15:44.34 |
+40:27:14.1 |
HIP 15282 |
16.66 |
| 2026-07-30 00:00 |
03:16:39.56 |
+40:30:03.6 |
HIP 15282 |
6.16 |
| 2026-07-30 12:00 |
03:17:34.72 |
+40:32:51.7 |
HIP 15282 |
5.88 |
| 2026-07-31 00:00 |
03:18:29.83 |
+40:35:38.3 |
HIP 15282 |
16.31 |
| 2026-07-31 12:00 |
03:19:24.88 |
+40:38:23.5 |
HIP 15494 |
20.50 |
| 2026-08-01 00:00 |
03:20:19.88 |
+40:41:07.2 |
HIP 15494 |
19.20 |
| 2026-08-01 12:00 |
03:21:14.82 |
+40:43:49.4 |
HIP 15494 |
23.42 |
| 2026-08-02 00:00 |
03:22:09.69 |
+40:46:30.1 |
HIP 15895 |
29.40 |
| 2026-08-02 12:00 |
03:23:04.50 |
+40:49:09.3 |
HIP 15895 |
19.32 |
| 2026-08-03 00:00 |
03:23:59.25 |
+40:51:47.0 |
HIP 15895 |
10.59 |
| 2026-08-03 12:00 |
03:24:53.93 |
+40:54:23.2 |
HIP 15944 |
5.59 |
| 2026-08-04 00:00 |
03:25:48.54 |
+40:56:57.8 |
HIP 15944 |
5.48 |
| 2026-08-04 12:00 |
03:26:43.08 |
+40:59:30.9 |
HIP 15944 |
15.94 |
| 2026-08-05 00:00 |
03:27:37.54 |
+41:02:02.5 |
HIP 15944 |
26.49 |
| 2026-08-05 12:00 |
03:28:31.92 |
+41:04:32.6 |
HIP 16317 |
33.53 |
| 2026-08-06 00:00 |
03:29:26.23 |
+41:07:01.1 |
HIP 16317 |
26.31 |
| 2026-08-06 12:00 |
03:30:20.46 |
+41:09:28.0 |
HIP 16317 |
21.96 |
| 2026-08-07 00:00 |
03:31:14.60 |
+41:11:53.4 |
HIP 16487 |
20.45 |
| 2026-08-07 12:00 |
03:32:08.65 |
+41:14:17.2 |
HIP 16487 |
19.12 |
| 2026-08-08 00:00 |
03:33:02.61 |
+41:16:39.4 |
HIP 16632 |
21.14 |
| 2026-08-08 12:00 |
03:33:56.49 |
+41:19:00.1 |
HIP 16632 |
20.53 |
| 2026-08-09 00:00 |
03:34:50.26 |
+41:21:19.1 |
HIP 16632 |
24.72 |
| 2026-08-09 12:00 |
03:35:43.95 |
+41:23:36.6 |
HIP 16632 |
31.84 |
| 2026-08-10 00:00 |
03:36:37.53 |
+41:25:52.4 |
HIP 17042 |
30.36 |
| 2026-08-10 12:00 |
03:37:31.00 |
+41:28:06.6 |
HIP 17042 |
22.01 |
| 2026-08-11 00:00 |
03:38:24.38 |
+41:30:19.1 |
HIP 17060 |
15.86 |
| 2026-08-11 12:00 |
03:39:17.64 |
+41:32:30.0 |
HIP 17060 |
8.83 |
| 2026-08-12 00:00 |
03:40:10.80 |
+41:34:39.3 |
HIP 17060 |
10.59 |
| 2026-08-12 12:00 |
03:41:03.84 |
+41:36:46.9 |
HIP 17189 |
13.97 |
| 2026-08-13 00:00 |
03:41:56.77 |
+41:38:52.9 |
HIP 17189 |
17.06 |
| 2026-08-13 12:00 |
03:42:49.57 |
+41:40:57.2 |
HIP 17189 |
24.28 |
| 2026-08-14 00:00 |
03:43:42.26 |
+41:42:59.8 |
HIP 17549 |
26.72 |
| 2026-08-14 12:00 |
03:44:34.82 |
+41:45:00.7 |
HIP 17549 |
18.63 |
| 2026-08-15 00:00 |
03:45:27.26 |
+41:46:59.9 |
HIP 17549 |
13.44 |
| 2026-08-15 12:00 |
03:46:19.57 |
+41:48:57.4 |
HIP 17655 |
6.72 |
| 2026-08-16 00:00 |
03:47:11.75 |
+41:50:53.2 |
HIP 17655 |
3.58 |
| 2026-08-16 12:00 |
03:48:03.80 |
+41:52:47.3 |
HIP 17655 |
13.26 |
| 2026-08-17 00:00 |
03:48:55.71 |
+41:54:39.6 |
HIP 17655 |
23.07 |
| 2026-08-17 12:00 |
03:49:47.48 |
+41:56:30.2 |
HIP 17941 |
24.97 |
| 2026-08-18 00:00 |
03:50:39.11 |
+41:58:19.1 |
HIP 17941 |
23.29 |
| 2026-08-18 12:00 |
03:51:30.60 |
+42:00:06.3 |
HIP 18162 |
23.13 |
| 2026-08-19 00:00 |
03:52:21.94 |
+42:01:51.7 |
HIP 18162 |
16.11 |