391P/Kowalski
| Parameter |
Value |
| Designation |
391P/Kowalski |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2008-02-19T23:23:38.063040Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:28:41Z |
| Obs used |
260 |
| NEO |
- |
| M1 |
9.900 |
| K1 |
10.000 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2019-10-22T00:19:10.848000Z |
| Discovery magnitude (MPC) |
20.30 N |
| Discovery observatory (MPC) |
J22 · Tacande Observatory, La Palma |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2008-09-05.0000000 |
| e |
0.11982312 |
| q (au) |
4.119481 |
| a (au) |
4.680287 |
| i (deg) |
21.274626 |
| Ω (om, deg) |
124.762161 |
| ω (w, deg) |
186.884849 |
| M (ma, deg) |
19.275953 |
Magnitude
Scatter + Global Linear
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
15:36:08.95 |
+02:27:35.9 |
HIP 76409 |
28.18 |
| 2026-02-03 12:00 |
15:36:25.48 |
+02:28:35.6 |
HIP 76409 |
26.98 |
| 2026-02-04 00:00 |
15:36:41.86 |
+02:29:36.4 |
HIP 76409 |
26.39 |
| 2026-02-04 12:00 |
15:36:58.09 |
+02:30:38.4 |
HIP 76409 |
26.43 |
| 2026-02-05 00:00 |
15:37:14.15 |
+02:31:41.5 |
HIP 76409 |
27.10 |
| 2026-02-05 12:00 |
15:37:30.06 |
+02:32:45.8 |
HIP 76409 |
28.32 |
| 2026-02-06 00:00 |
15:37:45.80 |
+02:33:51.2 |
HIP 76678 |
26.58 |
| 2026-02-06 12:00 |
15:38:01.39 |
+02:34:57.7 |
HIP 76678 |
22.53 |
| 2026-02-07 00:00 |
15:38:16.81 |
+02:36:05.4 |
HIP 76678 |
18.52 |
| 2026-02-07 12:00 |
15:38:32.07 |
+02:37:14.2 |
HIP 76678 |
14.55 |
| 2026-02-08 00:00 |
15:38:47.16 |
+02:38:24.2 |
HIP 76678 |
10.60 |
| 2026-02-08 12:00 |
15:39:02.09 |
+02:39:35.2 |
HIP 76678 |
6.69 |
| 2026-02-09 00:00 |
15:39:16.85 |
+02:40:47.4 |
HIP 76678 |
2.82 |
| 2026-02-09 12:00 |
15:39:31.45 |
+02:42:00.7 |
HIP 76678 |
1.06 |
| 2026-02-10 00:00 |
15:39:45.87 |
+02:43:15.1 |
HIP 76678 |
4.85 |
| 2026-02-10 12:00 |
15:40:00.13 |
+02:44:30.6 |
HIP 76678 |
8.62 |
| 2026-02-11 00:00 |
15:40:14.21 |
+02:45:47.2 |
HIP 76678 |
12.36 |
| 2026-02-11 12:00 |
15:40:28.12 |
+02:47:04.9 |
HIP 76818 |
10.27 |
| 2026-02-12 00:00 |
15:40:41.85 |
+02:48:23.7 |
HIP 76818 |
6.75 |
| 2026-02-12 12:00 |
15:40:55.41 |
+02:49:43.6 |
HIP 76818 |
3.58 |
| 2026-02-13 00:00 |
15:41:08.80 |
+02:51:04.6 |
HIP 76818 |
2.50 |
| 2026-02-13 12:00 |
15:41:22.00 |
+02:52:26.6 |
HIP 76818 |
5.02 |
| 2026-02-14 00:00 |
15:41:35.03 |
+02:53:49.7 |
HIP 76818 |
8.31 |
| 2026-02-14 12:00 |
15:41:47.88 |
+02:55:13.9 |
HIP 76818 |
11.70 |
| 2026-02-15 00:00 |
15:42:00.55 |
+02:56:39.1 |
HIP 76818 |
15.10 |
| 2026-02-15 12:00 |
15:42:13.04 |
+02:58:05.4 |
HIP 76915 |
15.60 |
| 2026-02-16 00:00 |
15:42:25.34 |
+02:59:32.8 |
HIP 76915 |
14.19 |
| 2026-02-16 12:00 |
15:42:37.46 |
+03:01:01.2 |
HIP 76915 |
13.47 |
| 2026-02-17 00:00 |
15:42:49.40 |
+03:02:30.6 |
HIP 76915 |
13.54 |
| 2026-02-17 12:00 |
15:43:01.15 |
+03:04:01.0 |
HIP 76915 |
14.36 |
| 2026-02-18 00:00 |
15:43:12.71 |
+03:05:32.4 |
HIP 76915 |
15.78 |
| 2026-02-18 12:00 |
15:43:24.09 |
+03:07:04.9 |
HIP 76915 |
17.65 |
| 2026-02-19 00:00 |
15:43:35.27 |
+03:08:38.4 |
HIP 77094 |
19.30 |
| 2026-02-19 12:00 |
15:43:46.27 |
+03:10:12.8 |
HIP 77094 |
16.26 |
| 2026-02-20 00:00 |
15:43:57.08 |
+03:11:48.2 |
HIP 77094 |
13.30 |
| 2026-02-20 12:00 |
15:44:07.69 |
+03:13:24.6 |
HIP 77094 |
10.45 |
| 2026-02-21 00:00 |
15:44:18.12 |
+03:15:02.0 |
HIP 77094 |
7.79 |
| 2026-02-21 12:00 |
15:44:28.35 |
+03:16:40.3 |
HIP 77094 |
5.56 |
| 2026-02-22 00:00 |
15:44:38.38 |
+03:18:19.6 |
HIP 77094 |
4.38 |
| 2026-02-22 12:00 |
15:44:48.23 |
+03:19:59.8 |
HIP 77094 |
5.00 |
| 2026-02-23 00:00 |
15:44:57.87 |
+03:21:40.9 |
HIP 77094 |
6.91 |
| 2026-02-23 12:00 |
15:45:07.32 |
+03:23:23.0 |
HIP 77094 |
9.32 |
| 2026-02-24 00:00 |
15:45:16.58 |
+03:25:05.9 |
HIP 77094 |
11.91 |