| 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) |
| 2026-05-12 00:00 |
17:09:25.62 |
-29:37:55.0 |
HIP 83931 |
16.15 |
| 2026-05-12 12:00 |
17:09:22.68 |
-29:37:55.5 |
HIP 83931 |
16.11 |
| 2026-05-13 00:00 |
17:09:19.73 |
-29:37:55.9 |
HIP 83931 |
16.10 |
| 2026-05-13 12:00 |
17:09:16.77 |
-29:37:56.3 |
HIP 83931 |
16.12 |
| 2026-05-14 00:00 |
17:09:13.79 |
-29:37:56.7 |
HIP 83931 |
16.16 |
| 2026-05-14 12:00 |
17:09:10.80 |
-29:37:56.9 |
HIP 83931 |
16.23 |
| 2026-05-15 00:00 |
17:09:07.80 |
-29:37:57.2 |
HIP 83931 |
16.33 |
| 2026-05-15 12:00 |
17:09:04.79 |
-29:37:57.3 |
HIP 83931 |
16.45 |
| 2026-05-16 00:00 |
17:09:01.77 |
-29:37:57.5 |
HIP 83931 |
16.60 |
| 2026-05-16 12:00 |
17:08:58.74 |
-29:37:57.5 |
HIP 83931 |
16.77 |
| 2026-05-17 00:00 |
17:08:55.70 |
-29:37:57.5 |
HIP 83931 |
16.97 |
| 2026-05-17 12:00 |
17:08:52.64 |
-29:37:57.5 |
HIP 83931 |
17.20 |
| 2026-05-18 00:00 |
17:08:49.58 |
-29:37:57.4 |
HIP 83931 |
17.45 |
| 2026-05-18 12:00 |
17:08:46.51 |
-29:37:57.3 |
HIP 83931 |
17.72 |
| 2026-05-19 00:00 |
17:08:43.42 |
-29:37:57.1 |
HIP 83931 |
18.02 |
| 2026-05-19 12:00 |
17:08:40.33 |
-29:37:56.8 |
HIP 83931 |
18.33 |
| 2026-05-20 00:00 |
17:08:37.23 |
-29:37:56.5 |
HIP 83931 |
18.67 |
| 2026-05-20 12:00 |
17:08:34.12 |
-29:37:56.2 |
HIP 83931 |
19.02 |
| 2026-05-21 00:00 |
17:08:31.00 |
-29:37:55.8 |
HIP 83931 |
19.40 |
| 2026-05-21 12:00 |
17:08:27.87 |
-29:37:55.3 |
HIP 83931 |
19.79 |
| 2026-05-22 00:00 |
17:08:24.74 |
-29:37:54.8 |
HIP 83931 |
20.20 |
| 2026-05-22 12:00 |
17:08:21.60 |
-29:37:54.2 |
HIP 83931 |
20.63 |
| 2026-05-23 00:00 |
17:08:18.45 |
-29:37:53.6 |
HIP 83931 |
21.07 |
| 2026-05-23 12:00 |
17:08:15.29 |
-29:37:53.0 |
HIP 83871 |
21.52 |
| 2026-05-24 00:00 |
17:08:12.12 |
-29:37:52.2 |
HIP 83871 |
21.65 |
| 2026-05-24 12:00 |
17:08:08.95 |
-29:37:51.5 |
HIP 83871 |
21.80 |
| 2026-05-25 00:00 |
17:08:05.77 |
-29:37:50.7 |
HIP 83871 |
21.97 |
| 2026-05-25 12:00 |
17:08:02.59 |
-29:37:49.8 |
HIP 83871 |
22.17 |
| 2026-05-26 00:00 |
17:07:59.40 |
-29:37:48.9 |
HIP 83871 |
22.39 |
| 2026-05-26 12:00 |
17:07:56.20 |
-29:37:47.9 |
HIP 83871 |
22.62 |
| 2026-05-27 00:00 |
17:07:52.99 |
-29:37:46.9 |
HIP 83871 |
22.88 |
| 2026-05-27 12:00 |
17:07:49.79 |
-29:37:45.8 |
HIP 83871 |
23.16 |
| 2026-05-28 00:00 |
17:07:46.57 |
-29:37:44.7 |
HIP 83871 |
23.45 |
| 2026-05-28 12:00 |
17:07:43.35 |
-29:37:43.5 |
HIP 83871 |
23.76 |
| 2026-05-29 00:00 |
17:07:40.13 |
-29:37:42.3 |
HIP 83871 |
24.09 |
| 2026-05-29 12:00 |
17:07:36.90 |
-29:37:41.0 |
HIP 83871 |
24.44 |
| 2026-05-30 00:00 |
17:07:33.66 |
-29:37:39.7 |
HIP 83871 |
24.80 |
| 2026-05-30 12:00 |
17:07:30.43 |
-29:37:38.3 |
HIP 83871 |
25.18 |
| 2026-05-31 00:00 |
17:07:27.18 |
-29:37:36.9 |
HIP 83871 |
25.58 |
| 2026-05-31 12:00 |
17:07:23.94 |
-29:37:35.4 |
HIP 83871 |
25.98 |
| 2026-06-01 00:00 |
17:07:20.69 |
-29:37:33.9 |
HIP 83871 |
26.40 |
| 2026-06-01 12:00 |
17:07:17.44 |
-29:37:32.4 |
HIP 83871 |
26.84 |
| 2026-06-02 00:00 |
17:07:14.18 |
-29:37:30.7 |
HIP 83871 |
27.29 |