104P/Kowal 2
| Parameter |
Value |
| Designation |
104P/Kowal 2 |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2022-01-11T14:49:09.753600Z |
| Orbit solution date (soln_date, UTC) |
2023-04-05T03:16:58Z |
| Obs used |
1551 |
| NEO |
Yes |
| M1 |
14.600 |
| K1 |
12.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2021-09-29.0000000 |
| e |
0.66545272 |
| q (au) |
1.073098 |
| a (au) |
3.207614 |
| i (deg) |
5.701090 |
| Ω (om, deg) |
207.213526 |
| ω (w, deg) |
227.245888 |
| M (ma, deg) |
342.051208 |
Magnitude
Scatter + Global Linear
$$
M_a = (13.882 + 3.137\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.882 |
| n |
3.137 |
| gf |
1.000 |
| gb |
-0.500 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2021-08-11 |
2021-11-29 |
+3.2064 |
+1.741 |
| 2021-11-29 |
2022-01-11 |
+71.5132 |
-3.914 |
| 2022-01-11 |
2022-07-20 |
-2.8823 |
-1.387 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
18:52:36.33 |
-18:20:00.5 |
HIP 92662 |
6.46 |
| 2026-02-03 12:00 |
18:53:02.78 |
-18:19:11.0 |
HIP 92662 |
3.97 |
| 2026-02-04 00:00 |
18:53:29.18 |
-18:18:21.2 |
HIP 92662 |
8.35 |
| 2026-02-04 12:00 |
18:53:55.53 |
-18:17:30.9 |
HIP 92662 |
14.26 |
| 2026-02-05 00:00 |
18:54:21.82 |
-18:16:40.2 |
HIP 92662 |
20.40 |
| 2026-02-05 12:00 |
18:54:48.06 |
-18:15:49.2 |
HIP 92912 |
21.85 |
| 2026-02-06 00:00 |
18:55:14.24 |
-18:14:57.8 |
HIP 92912 |
19.03 |
| 2026-02-06 12:00 |
18:55:40.36 |
-18:14:06.0 |
HIP 92912 |
18.05 |
| 2026-02-07 00:00 |
18:56:06.43 |
-18:13:13.8 |
HIP 92917 |
18.85 |
| 2026-02-07 12:00 |
18:56:32.44 |
-18:12:21.3 |
HIP 92917 |
20.04 |
| 2026-02-08 00:00 |
18:56:58.38 |
-18:11:28.4 |
HIP 92917 |
22.92 |
| 2026-02-08 12:00 |
18:57:24.27 |
-18:10:35.1 |
HIP 92917 |
26.94 |
| 2026-02-09 00:00 |
18:57:50.09 |
-18:09:41.5 |
HIP 92917 |
31.67 |
| 2026-02-09 12:00 |
18:58:15.86 |
-18:08:47.5 |
HIP 93293 |
27.43 |
| 2026-02-10 00:00 |
18:58:41.56 |
-18:07:53.2 |
HIP 93293 |
21.82 |
| 2026-02-10 12:00 |
18:59:07.19 |
-18:06:58.5 |
HIP 93293 |
16.64 |
| 2026-02-11 00:00 |
18:59:32.76 |
-18:06:03.4 |
HIP 93293 |
12.40 |
| 2026-02-11 12:00 |
18:59:58.27 |
-18:05:08.0 |
HIP 93293 |
10.31 |
| 2026-02-12 00:00 |
19:00:23.70 |
-18:04:12.3 |
HIP 93293 |
11.57 |
| 2026-02-12 12:00 |
19:00:49.07 |
-18:03:16.2 |
HIP 93293 |
15.36 |
| 2026-02-13 00:00 |
19:01:14.37 |
-18:02:19.8 |
HIP 93293 |
20.30 |
| 2026-02-13 12:00 |
19:01:39.60 |
-18:01:23.0 |
HIP 93293 |
25.72 |
| 2026-02-14 00:00 |
19:02:04.76 |
-18:00:25.9 |
HIP 93293 |
31.37 |
| 2026-02-14 12:00 |
19:02:29.85 |
-17:59:28.5 |
HIP 93644 |
27.29 |
| 2026-02-15 00:00 |
19:02:54.86 |
-17:58:30.7 |
HIP 93644 |
21.78 |
| 2026-02-15 12:00 |
19:03:19.80 |
-17:57:32.7 |
HIP 93644 |
16.65 |
| 2026-02-16 00:00 |
19:03:44.66 |
-17:56:34.3 |
HIP 93644 |
12.34 |
| 2026-02-16 12:00 |
19:04:09.45 |
-17:55:35.6 |
HIP 93644 |
9.95 |
| 2026-02-17 00:00 |
19:04:34.16 |
-17:54:36.6 |
HIP 93693 |
7.15 |
| 2026-02-17 12:00 |
19:04:58.80 |
-17:53:37.2 |
HIP 93693 |
6.24 |
| 2026-02-18 00:00 |
19:05:23.35 |
-17:52:37.6 |
HIP 93693 |
9.86 |
| 2026-02-18 12:00 |
19:05:47.82 |
-17:51:37.7 |
HIP 93693 |
15.00 |
| 2026-02-19 00:00 |
19:06:12.21 |
-17:50:37.5 |
HIP 93693 |
20.54 |
| 2026-02-19 12:00 |
19:06:36.52 |
-17:49:37.0 |
HIP 93693 |
26.21 |
| 2026-02-20 00:00 |
19:07:00.75 |
-17:48:36.2 |
HIP 93693 |
31.94 |
| 2026-02-20 12:00 |
19:07:24.89 |
-17:47:35.1 |
HIP 94061 |
26.82 |
| 2026-02-21 00:00 |
19:07:48.95 |
-17:46:33.7 |
HIP 94061 |
21.69 |
| 2026-02-21 12:00 |
19:08:12.92 |
-17:45:32.1 |
HIP 94061 |
17.01 |
| 2026-02-22 00:00 |
19:08:36.81 |
-17:44:30.2 |
HIP 94061 |
13.27 |
| 2026-02-22 12:00 |
19:09:00.60 |
-17:43:28.0 |
HIP 94061 |
11.37 |
| 2026-02-23 00:00 |
19:09:24.31 |
-17:42:25.5 |
HIP 94061 |
12.20 |
| 2026-02-23 12:00 |
19:09:47.93 |
-17:41:22.8 |
HIP 94061 |
15.28 |
| 2026-02-24 00:00 |
19:10:11.45 |
-17:40:19.9 |
HIP 94061 |
19.57 |