| 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) |
| 2026-03-26 00:00 |
15:48:09.40 |
+05:28:40.7 |
HIP 77489 |
31.37 |
| 2026-03-26 12:00 |
15:48:05.68 |
+05:30:55.8 |
HIP 77489 |
33.75 |
| 2026-03-27 00:00 |
15:48:01.75 |
+05:33:10.9 |
HIP 77204 |
35.22 |
| 2026-03-27 12:00 |
15:47:57.61 |
+05:35:26.0 |
HIP 77204 |
35.21 |
| 2026-03-28 00:00 |
15:47:53.25 |
+05:37:41.0 |
HIP 77204 |
35.33 |
| 2026-03-28 12:00 |
15:47:48.69 |
+05:39:56.0 |
HIP 77204 |
35.58 |
| 2026-03-29 00:00 |
15:47:43.91 |
+05:42:11.0 |
HIP 77237 |
33.21 |
| 2026-03-29 12:00 |
15:47:38.92 |
+05:44:25.8 |
HIP 77237 |
30.72 |
| 2026-03-30 00:00 |
15:47:33.72 |
+05:46:40.5 |
HIP 77237 |
28.21 |
| 2026-03-30 12:00 |
15:47:28.31 |
+05:48:55.1 |
HIP 77237 |
25.68 |
| 2026-03-31 00:00 |
15:47:22.69 |
+05:51:09.6 |
HIP 77237 |
23.13 |
| 2026-03-31 12:00 |
15:47:16.87 |
+05:53:23.9 |
HIP 77237 |
20.56 |
| 2026-04-01 00:00 |
15:47:10.84 |
+05:55:37.9 |
HIP 77237 |
17.99 |
| 2026-04-01 12:00 |
15:47:04.60 |
+05:57:51.8 |
HIP 77237 |
15.42 |
| 2026-04-02 00:00 |
15:46:58.16 |
+06:00:05.5 |
HIP 77237 |
12.86 |
| 2026-04-02 12:00 |
15:46:51.51 |
+06:02:18.9 |
HIP 77237 |
10.36 |
| 2026-04-03 00:00 |
15:46:44.66 |
+06:04:32.0 |
HIP 77237 |
7.98 |
| 2026-04-03 12:00 |
15:46:37.61 |
+06:06:44.9 |
HIP 77237 |
5.94 |
| 2026-04-04 00:00 |
15:46:30.36 |
+06:08:57.4 |
HIP 77237 |
4.72 |
| 2026-04-04 12:00 |
15:46:22.90 |
+06:11:09.6 |
HIP 77237 |
5.04 |
| 2026-04-05 00:00 |
15:46:15.24 |
+06:13:21.5 |
HIP 77237 |
6.70 |
| 2026-04-05 12:00 |
15:46:07.39 |
+06:15:32.9 |
HIP 77237 |
9.01 |
| 2026-04-06 00:00 |
15:45:59.34 |
+06:17:44.0 |
HIP 77237 |
11.62 |
| 2026-04-06 12:00 |
15:45:51.09 |
+06:19:54.7 |
HIP 77237 |
14.38 |
| 2026-04-07 00:00 |
15:45:42.64 |
+06:22:04.9 |
HIP 77237 |
17.24 |
| 2026-04-07 12:00 |
15:45:34.00 |
+06:24:14.6 |
HIP 77070 |
19.42 |
| 2026-04-08 00:00 |
15:45:25.17 |
+06:26:23.9 |
HIP 77070 |
17.21 |
| 2026-04-08 12:00 |
15:45:16.15 |
+06:28:32.7 |
HIP 77070 |
15.24 |
| 2026-04-09 00:00 |
15:45:06.93 |
+06:30:40.9 |
HIP 77070 |
13.66 |
| 2026-04-09 12:00 |
15:44:57.53 |
+06:32:48.6 |
HIP 77070 |
12.63 |
| 2026-04-10 00:00 |
15:44:47.94 |
+06:34:55.7 |
HIP 77070 |
12.30 |
| 2026-04-10 12:00 |
15:44:38.16 |
+06:37:02.2 |
HIP 77070 |
12.75 |
| 2026-04-11 00:00 |
15:44:28.19 |
+06:39:08.0 |
HIP 77070 |
13.94 |
| 2026-04-11 12:00 |
15:44:18.04 |
+06:41:13.3 |
HIP 77070 |
15.70 |
| 2026-04-12 00:00 |
15:44:07.71 |
+06:43:17.8 |
HIP 76965 |
17.54 |
| 2026-04-12 12:00 |
15:43:57.20 |
+06:45:21.7 |
HIP 76965 |
15.11 |
| 2026-04-13 00:00 |
15:43:46.52 |
+06:47:24.8 |
HIP 76965 |
13.03 |
| 2026-04-13 12:00 |
15:43:35.65 |
+06:49:27.2 |
HIP 76959 |
11.49 |
| 2026-04-14 00:00 |
15:43:24.61 |
+06:51:28.9 |
HIP 76959 |
8.32 |
| 2026-04-14 12:00 |
15:43:13.39 |
+06:53:29.7 |
HIP 76964 |
5.13 |
| 2026-04-15 00:00 |
15:43:02.01 |
+06:55:29.8 |
HIP 76964 |
1.84 |
| 2026-04-15 12:00 |
15:42:50.45 |
+06:57:29.0 |
HIP 76964 |
2.12 |
| 2026-04-16 00:00 |
15:42:38.73 |
+06:59:27.3 |
HIP 76964 |
5.49 |