| Parameter |
Value |
| Designation |
C/2000 O1 (Koehn) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2000-01-27T17:38:15.144000Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:05Z |
| Obs used |
64 |
| NEO |
- |
| M1 |
5.100 |
| K1 |
11.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2000-05-14.0000000 |
| e |
1.00000217 |
| q (au) |
5.921780 |
| a (au) |
-2729545.221721 |
| i (deg) |
148.104189 |
| Ω (om, deg) |
88.882672 |
| ω (w, deg) |
55.164253 |
| M (ma, deg) |
0.000000 |
Magnitude
Scatter + Global Linear
$$
M_a = (2.023 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
2.023 |
| n |
6.000 |
| gf |
0.999 |
| gb |
-1.000 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
17:12:41.52 |
-29:33:23.4 |
HIP 84222 |
4.96 |
| 2026-03-26 12:00 |
17:12:40.48 |
-29:33:28.4 |
HIP 84222 |
5.04 |
| 2026-03-27 00:00 |
17:12:39.42 |
-29:33:33.3 |
HIP 84222 |
5.14 |
| 2026-03-27 12:00 |
17:12:38.33 |
-29:33:38.2 |
HIP 84222 |
5.25 |
| 2026-03-28 00:00 |
17:12:37.22 |
-29:33:43.1 |
HIP 84222 |
5.38 |
| 2026-03-28 12:00 |
17:12:36.08 |
-29:33:47.9 |
HIP 84222 |
5.52 |
| 2026-03-29 00:00 |
17:12:34.92 |
-29:33:52.7 |
HIP 84222 |
5.68 |
| 2026-03-29 12:00 |
17:12:33.73 |
-29:33:57.5 |
HIP 84222 |
5.85 |
| 2026-03-30 00:00 |
17:12:32.52 |
-29:34:02.2 |
HIP 84222 |
6.03 |
| 2026-03-30 12:00 |
17:12:31.28 |
-29:34:06.8 |
HIP 84222 |
6.22 |
| 2026-03-31 00:00 |
17:12:30.02 |
-29:34:11.5 |
HIP 84222 |
6.42 |
| 2026-03-31 12:00 |
17:12:28.73 |
-29:34:16.1 |
HIP 84222 |
6.64 |
| 2026-04-01 00:00 |
17:12:27.41 |
-29:34:20.6 |
HIP 84222 |
6.86 |
| 2026-04-01 12:00 |
17:12:26.08 |
-29:34:25.1 |
HIP 84222 |
7.10 |
| 2026-04-02 00:00 |
17:12:24.71 |
-29:34:29.6 |
HIP 84222 |
7.34 |
| 2026-04-02 12:00 |
17:12:23.32 |
-29:34:34.0 |
HIP 84222 |
7.60 |
| 2026-04-03 00:00 |
17:12:21.91 |
-29:34:38.4 |
HIP 84222 |
7.86 |
| 2026-04-03 12:00 |
17:12:20.47 |
-29:34:42.8 |
HIP 84131 |
8.11 |
| 2026-04-04 00:00 |
17:12:19.01 |
-29:34:47.1 |
HIP 84131 |
7.97 |
| 2026-04-04 12:00 |
17:12:17.52 |
-29:34:51.3 |
HIP 84131 |
7.84 |
| 2026-04-05 00:00 |
17:12:16.01 |
-29:34:55.6 |
HIP 84131 |
7.71 |
| 2026-04-05 12:00 |
17:12:14.48 |
-29:34:59.7 |
HIP 84131 |
7.59 |
| 2026-04-06 00:00 |
17:12:12.92 |
-29:35:03.9 |
HIP 84131 |
7.49 |
| 2026-04-06 12:00 |
17:12:11.34 |
-29:35:08.0 |
HIP 84131 |
7.39 |
| 2026-04-07 00:00 |
17:12:09.73 |
-29:35:12.0 |
HIP 84131 |
7.31 |
| 2026-04-07 12:00 |
17:12:08.10 |
-29:35:16.0 |
HIP 84131 |
7.24 |
| 2026-04-08 00:00 |
17:12:06.44 |
-29:35:20.0 |
HIP 84131 |
7.19 |
| 2026-04-08 12:00 |
17:12:04.76 |
-29:35:23.9 |
HIP 84131 |
7.15 |
| 2026-04-09 00:00 |
17:12:03.06 |
-29:35:27.8 |
HIP 84131 |
7.14 |
| 2026-04-09 12:00 |
17:12:01.34 |
-29:35:31.6 |
HIP 84131 |
7.14 |
| 2026-04-10 00:00 |
17:11:59.59 |
-29:35:35.4 |
HIP 84131 |
7.15 |
| 2026-04-10 12:00 |
17:11:57.81 |
-29:35:39.1 |
HIP 84131 |
7.19 |
| 2026-04-11 00:00 |
17:11:56.02 |
-29:35:42.8 |
HIP 84131 |
7.25 |
| 2026-04-11 12:00 |
17:11:54.20 |
-29:35:46.5 |
HIP 84131 |
7.33 |
| 2026-04-12 00:00 |
17:11:52.36 |
-29:35:50.1 |
HIP 84131 |
7.43 |
| 2026-04-12 12:00 |
17:11:50.49 |
-29:35:53.6 |
HIP 84131 |
7.55 |
| 2026-04-13 00:00 |
17:11:48.61 |
-29:35:57.1 |
HIP 84131 |
7.69 |
| 2026-04-13 12:00 |
17:11:46.70 |
-29:36:00.6 |
HIP 84131 |
7.85 |
| 2026-04-14 00:00 |
17:11:44.76 |
-29:36:04.0 |
HIP 84131 |
8.03 |
| 2026-04-14 12:00 |
17:11:42.81 |
-29:36:07.4 |
HIP 84131 |
8.23 |
| 2026-04-15 00:00 |
17:11:40.83 |
-29:36:10.7 |
HIP 84131 |
8.45 |
| 2026-04-15 12:00 |
17:11:38.83 |
-29:36:14.0 |
HIP 84131 |
8.69 |
| 2026-04-16 00:00 |
17:11:36.81 |
-29:36:17.2 |
HIP 84131 |
8.94 |