| Parameter |
Value |
| Designation |
C/2011 S2 (Kowalski) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2011-10-26T08:20:46.965120Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:56Z |
| Obs used |
343 |
| NEO |
Yes |
| M1 |
15.600 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2011-10-23.0000000 |
| e |
0.93161485 |
| q (au) |
1.115120 |
| a (au) |
16.306469 |
| i (deg) |
17.572538 |
| Ω (om, deg) |
288.070325 |
| ω (w, deg) |
192.189985 |
| M (ma, deg) |
359.949891 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.975 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.975 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.701 |
| k |
0.800 |
| 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) |
| 2026-03-26 00:00 |
19:30:11.91 |
-21:37:56.7 |
HIP 95855 |
18.83 |
| 2026-03-26 12:00 |
19:30:13.60 |
-21:37:51.6 |
HIP 95855 |
18.89 |
| 2026-03-27 00:00 |
19:30:15.24 |
-21:37:46.5 |
HIP 95855 |
18.96 |
| 2026-03-27 12:00 |
19:30:16.85 |
-21:37:41.6 |
HIP 95855 |
19.03 |
| 2026-03-28 00:00 |
19:30:18.41 |
-21:37:36.7 |
HIP 95855 |
19.11 |
| 2026-03-28 12:00 |
19:30:19.93 |
-21:37:31.9 |
HIP 95855 |
19.19 |
| 2026-03-29 00:00 |
19:30:21.41 |
-21:37:27.2 |
HIP 95855 |
19.28 |
| 2026-03-29 12:00 |
19:30:22.84 |
-21:37:22.5 |
HIP 95855 |
19.37 |
| 2026-03-30 00:00 |
19:30:24.24 |
-21:37:18.0 |
HIP 95855 |
19.46 |
| 2026-03-30 12:00 |
19:30:25.59 |
-21:37:13.6 |
HIP 95855 |
19.55 |
| 2026-03-31 00:00 |
19:30:26.90 |
-21:37:09.2 |
HIP 95965 |
19.47 |
| 2026-03-31 12:00 |
19:30:28.17 |
-21:37:04.9 |
HIP 95965 |
19.31 |
| 2026-04-01 00:00 |
19:30:29.40 |
-21:37:00.8 |
HIP 95965 |
19.16 |
| 2026-04-01 12:00 |
19:30:30.59 |
-21:36:56.7 |
HIP 95965 |
19.01 |
| 2026-04-02 00:00 |
19:30:31.73 |
-21:36:52.7 |
HIP 95965 |
18.87 |
| 2026-04-02 12:00 |
19:30:32.83 |
-21:36:48.8 |
HIP 95965 |
18.74 |
| 2026-04-03 00:00 |
19:30:33.89 |
-21:36:44.9 |
HIP 95965 |
18.62 |
| 2026-04-03 12:00 |
19:30:34.91 |
-21:36:41.2 |
HIP 95965 |
18.50 |
| 2026-04-04 00:00 |
19:30:35.88 |
-21:36:37.6 |
HIP 95965 |
18.39 |
| 2026-04-04 12:00 |
19:30:36.82 |
-21:36:34.0 |
HIP 95965 |
18.28 |
| 2026-04-05 00:00 |
19:30:37.70 |
-21:36:30.5 |
HIP 95965 |
18.18 |
| 2026-04-05 12:00 |
19:30:38.55 |
-21:36:27.2 |
HIP 95965 |
18.08 |
| 2026-04-06 00:00 |
19:30:39.36 |
-21:36:23.9 |
HIP 95965 |
17.99 |
| 2026-04-06 12:00 |
19:30:40.12 |
-21:36:20.7 |
HIP 95965 |
17.91 |
| 2026-04-07 00:00 |
19:30:40.84 |
-21:36:17.6 |
HIP 95965 |
17.83 |
| 2026-04-07 12:00 |
19:30:41.51 |
-21:36:14.6 |
HIP 95965 |
17.75 |
| 2026-04-08 00:00 |
19:30:42.14 |
-21:36:11.7 |
HIP 95965 |
17.68 |
| 2026-04-08 12:00 |
19:30:42.73 |
-21:36:08.8 |
HIP 95965 |
17.61 |
| 2026-04-09 00:00 |
19:30:43.28 |
-21:36:06.1 |
HIP 95965 |
17.55 |
| 2026-04-09 12:00 |
19:30:43.78 |
-21:36:03.5 |
HIP 95965 |
17.49 |
| 2026-04-10 00:00 |
19:30:44.24 |
-21:36:00.9 |
HIP 95965 |
17.43 |
| 2026-04-10 12:00 |
19:30:44.66 |
-21:35:58.5 |
HIP 95965 |
17.38 |
| 2026-04-11 00:00 |
19:30:45.03 |
-21:35:56.1 |
HIP 95965 |
17.33 |
| 2026-04-11 12:00 |
19:30:45.36 |
-21:35:53.8 |
HIP 95965 |
17.28 |
| 2026-04-12 00:00 |
19:30:45.65 |
-21:35:51.6 |
HIP 95965 |
17.24 |
| 2026-04-12 12:00 |
19:30:45.89 |
-21:35:49.6 |
HIP 95965 |
17.20 |
| 2026-04-13 00:00 |
19:30:46.09 |
-21:35:47.6 |
HIP 95965 |
17.16 |
| 2026-04-13 12:00 |
19:30:46.25 |
-21:35:45.7 |
HIP 95965 |
17.13 |
| 2026-04-14 00:00 |
19:30:46.36 |
-21:35:43.9 |
HIP 95965 |
17.09 |
| 2026-04-14 12:00 |
19:30:46.43 |
-21:35:42.1 |
HIP 95965 |
17.06 |
| 2026-04-15 00:00 |
19:30:46.45 |
-21:35:40.5 |
HIP 95965 |
17.04 |
| 2026-04-15 12:00 |
19:30:46.43 |
-21:35:39.0 |
HIP 95965 |
17.01 |
| 2026-04-16 00:00 |
19:30:46.37 |
-21:35:37.6 |
HIP 95965 |
16.99 |