| Parameter |
Value |
| Designation |
C/1967 C1 (Seki) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1967-03-13T17:47:57.289920Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:17Z |
| Obs used |
18 |
| NEO |
- |
| M1 |
10.600 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1967-02-14.0000000 |
| e |
0.99990293 |
| q (au) |
0.457380 |
| a (au) |
4712.068054 |
| i (deg) |
106.468426 |
| Ω (om, deg) |
200.519565 |
| ω (w, deg) |
144.290739 |
| M (ma, deg) |
359.999915 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.171 + 3.612\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.171 |
| n |
3.612 |
| gf |
1.000 |
| gb |
-0.983 |
| 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) |
| 2026-06-01 00:00 |
12:46:49.41 |
-51:53:11.6 |
HIP 62225 |
15.54 |
| 2026-06-01 12:00 |
12:46:48.30 |
-51:52:55.6 |
HIP 62225 |
15.32 |
| 2026-06-02 00:00 |
12:46:47.19 |
-51:52:39.5 |
HIP 62225 |
15.11 |
| 2026-06-02 12:00 |
12:46:46.10 |
-51:52:23.3 |
HIP 62225 |
14.90 |
| 2026-06-03 00:00 |
12:46:45.03 |
-51:52:07.2 |
HIP 62225 |
14.70 |
| 2026-06-03 12:00 |
12:46:43.97 |
-51:51:51.0 |
HIP 62225 |
14.51 |
| 2026-06-04 00:00 |
12:46:42.93 |
-51:51:34.8 |
HIP 62225 |
14.33 |
| 2026-06-04 12:00 |
12:46:41.90 |
-51:51:18.6 |
HIP 62225 |
14.15 |
| 2026-06-05 00:00 |
12:46:40.89 |
-51:51:02.3 |
HIP 62225 |
13.98 |
| 2026-06-05 12:00 |
12:46:39.90 |
-51:50:46.1 |
HIP 62225 |
13.81 |
| 2026-06-06 00:00 |
12:46:38.92 |
-51:50:29.8 |
HIP 62225 |
13.65 |
| 2026-06-06 12:00 |
12:46:37.95 |
-51:50:13.5 |
HIP 62225 |
13.50 |
| 2026-06-07 00:00 |
12:46:37.00 |
-51:49:57.2 |
HIP 62225 |
13.36 |
| 2026-06-07 12:00 |
12:46:36.07 |
-51:49:40.9 |
HIP 62225 |
13.23 |
| 2026-06-08 00:00 |
12:46:35.16 |
-51:49:24.5 |
HIP 62225 |
13.10 |
| 2026-06-08 12:00 |
12:46:34.26 |
-51:49:08.2 |
HIP 62225 |
12.99 |
| 2026-06-09 00:00 |
12:46:33.37 |
-51:48:51.8 |
HIP 62225 |
12.88 |
| 2026-06-09 12:00 |
12:46:32.50 |
-51:48:35.4 |
HIP 62225 |
12.78 |
| 2026-06-10 00:00 |
12:46:31.65 |
-51:48:19.0 |
HIP 62225 |
12.69 |
| 2026-06-10 12:00 |
12:46:30.82 |
-51:48:02.6 |
HIP 62225 |
12.61 |
| 2026-06-11 00:00 |
12:46:30.00 |
-51:47:46.2 |
HIP 62225 |
12.54 |
| 2026-06-11 12:00 |
12:46:29.20 |
-51:47:29.8 |
HIP 62225 |
12.48 |
| 2026-06-12 00:00 |
12:46:28.41 |
-51:47:13.4 |
HIP 62225 |
12.42 |
| 2026-06-12 12:00 |
12:46:27.64 |
-51:46:57.0 |
HIP 62225 |
12.38 |
| 2026-06-13 00:00 |
12:46:26.89 |
-51:46:40.6 |
HIP 62225 |
12.35 |
| 2026-06-13 12:00 |
12:46:26.15 |
-51:46:24.2 |
HIP 62225 |
12.32 |
| 2026-06-14 00:00 |
12:46:25.43 |
-51:46:07.8 |
HIP 62225 |
12.31 |
| 2026-06-14 12:00 |
12:46:24.73 |
-51:45:51.3 |
HIP 62225 |
12.30 |
| 2026-06-15 00:00 |
12:46:24.04 |
-51:45:34.9 |
HIP 62225 |
12.31 |
| 2026-06-15 12:00 |
12:46:23.38 |
-51:45:18.5 |
HIP 62225 |
12.32 |
| 2026-06-16 00:00 |
12:46:22.72 |
-51:45:02.1 |
HIP 62225 |
12.34 |
| 2026-06-16 12:00 |
12:46:22.09 |
-51:44:45.7 |
HIP 62225 |
12.37 |
| 2026-06-17 00:00 |
12:46:21.47 |
-51:44:29.4 |
HIP 62225 |
12.41 |
| 2026-06-17 12:00 |
12:46:20.87 |
-51:44:13.0 |
HIP 62225 |
12.46 |
| 2026-06-18 00:00 |
12:46:20.29 |
-51:43:56.6 |
HIP 62225 |
12.52 |
| 2026-06-18 12:00 |
12:46:19.72 |
-51:43:40.3 |
HIP 62225 |
12.59 |
| 2026-06-19 00:00 |
12:46:19.17 |
-51:43:23.9 |
HIP 62225 |
12.66 |
| 2026-06-19 12:00 |
12:46:18.64 |
-51:43:07.6 |
HIP 62225 |
12.74 |
| 2026-06-20 00:00 |
12:46:18.12 |
-51:42:51.3 |
HIP 62225 |
12.83 |
| 2026-06-20 12:00 |
12:46:17.62 |
-51:42:35.0 |
HIP 62225 |
12.93 |
| 2026-06-21 00:00 |
12:46:17.14 |
-51:42:18.7 |
HIP 62225 |
13.04 |
| 2026-06-21 12:00 |
12:46:16.68 |
-51:42:02.5 |
HIP 62225 |
13.15 |
| 2026-06-22 00:00 |
12:46:16.23 |
-51:41:46.3 |
HIP 62225 |
13.27 |