| Parameter |
Value |
| Designation |
C/1968 N1 (Honda) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1968-08-07T22:10:35.492160Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:17Z |
| Obs used |
137 |
| NEO |
- |
| M1 |
5.200 |
| K1 |
12.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1968-09-04.0000000 |
| e |
1.00071634 |
| q (au) |
1.160438 |
| a (au) |
-1619.950396 |
| i (deg) |
143.238254 |
| Ω (om, deg) |
106.747265 |
| ω (w, deg) |
88.715828 |
| M (ma, deg) |
0.000409 |
Magnitude
Scatter + Global Linear
$$
M_a = (5.762 + 5.761\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
5.762 |
| n |
5.761 |
| gf |
1.000 |
| gb |
-0.601 |
| 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) |
| 2026-09-20 00:00 |
13:05:16.35 |
-45:18:17.6 |
HIP 63868 |
4.90 |
| 2026-09-20 12:00 |
13:05:18.05 |
-45:18:19.0 |
HIP 63868 |
4.81 |
| 2026-09-21 00:00 |
13:05:19.76 |
-45:18:20.5 |
HIP 63868 |
4.73 |
| 2026-09-21 12:00 |
13:05:21.48 |
-45:18:22.2 |
HIP 63868 |
4.67 |
| 2026-09-22 00:00 |
13:05:23.20 |
-45:18:24.0 |
HIP 63868 |
4.62 |
| 2026-09-22 12:00 |
13:05:24.92 |
-45:18:25.9 |
HIP 63868 |
4.59 |
| 2026-09-23 00:00 |
13:05:26.65 |
-45:18:27.9 |
HIP 63868 |
4.58 |
| 2026-09-23 12:00 |
13:05:28.39 |
-45:18:30.0 |
HIP 63868 |
4.59 |
| 2026-09-24 00:00 |
13:05:30.13 |
-45:18:32.3 |
HIP 63868 |
4.62 |
| 2026-09-24 12:00 |
13:05:31.87 |
-45:18:34.6 |
HIP 63868 |
4.67 |
| 2026-09-25 00:00 |
13:05:33.62 |
-45:18:37.1 |
HIP 63868 |
4.73 |
| 2026-09-25 12:00 |
13:05:35.37 |
-45:18:39.7 |
HIP 63868 |
4.81 |
| 2026-09-26 00:00 |
13:05:37.13 |
-45:18:42.5 |
HIP 63868 |
4.91 |
| 2026-09-26 12:00 |
13:05:38.89 |
-45:18:45.3 |
HIP 63868 |
5.03 |
| 2026-09-27 00:00 |
13:05:40.65 |
-45:18:48.3 |
HIP 63868 |
5.16 |
| 2026-09-27 12:00 |
13:05:42.42 |
-45:18:51.4 |
HIP 63868 |
5.30 |
| 2026-09-28 00:00 |
13:05:44.19 |
-45:18:54.6 |
HIP 63868 |
5.46 |
| 2026-09-28 12:00 |
13:05:45.96 |
-45:18:58.0 |
HIP 63868 |
5.63 |
| 2026-09-29 00:00 |
13:05:47.74 |
-45:19:01.4 |
HIP 63868 |
5.81 |
| 2026-09-29 12:00 |
13:05:49.52 |
-45:19:05.0 |
HIP 63868 |
6.01 |
| 2026-09-30 00:00 |
13:05:51.31 |
-45:19:08.7 |
HIP 63868 |
6.21 |
| 2026-09-30 12:00 |
13:05:53.10 |
-45:19:12.5 |
HIP 63868 |
6.42 |
| 2026-10-01 00:00 |
13:05:54.89 |
-45:19:16.4 |
HIP 63868 |
6.64 |
| 2026-10-01 12:00 |
13:05:56.68 |
-45:19:20.5 |
HIP 63868 |
6.86 |
| 2026-10-02 00:00 |
13:05:58.48 |
-45:19:24.6 |
HIP 63868 |
7.10 |
| 2026-10-02 12:00 |
13:06:00.28 |
-45:19:28.9 |
HIP 63868 |
7.33 |
| 2026-10-03 00:00 |
13:06:02.08 |
-45:19:33.3 |
HIP 63868 |
7.58 |
| 2026-10-03 12:00 |
13:06:03.88 |
-45:19:37.8 |
HIP 63868 |
7.83 |
| 2026-10-04 00:00 |
13:06:05.69 |
-45:19:42.5 |
HIP 63868 |
8.08 |
| 2026-10-04 12:00 |
13:06:07.50 |
-45:19:47.2 |
HIP 63868 |
8.34 |
| 2026-10-05 00:00 |
13:06:09.31 |
-45:19:52.1 |
HIP 63868 |
8.61 |
| 2026-10-05 12:00 |
13:06:11.12 |
-45:19:57.1 |
HIP 63868 |
8.88 |
| 2026-10-06 00:00 |
13:06:12.93 |
-45:20:02.2 |
HIP 63868 |
9.15 |
| 2026-10-06 12:00 |
13:06:14.75 |
-45:20:07.4 |
HIP 63868 |
9.42 |
| 2026-10-07 00:00 |
13:06:16.56 |
-45:20:12.7 |
HIP 63868 |
9.70 |
| 2026-10-07 12:00 |
13:06:18.38 |
-45:20:18.2 |
HIP 63868 |
9.98 |
| 2026-10-08 00:00 |
13:06:20.20 |
-45:20:23.7 |
HIP 63868 |
10.26 |
| 2026-10-08 12:00 |
13:06:22.02 |
-45:20:29.4 |
HIP 63868 |
10.55 |
| 2026-10-09 00:00 |
13:06:23.84 |
-45:20:35.2 |
HIP 63868 |
10.84 |
| 2026-10-09 12:00 |
13:06:25.66 |
-45:20:41.1 |
HIP 63868 |
11.13 |
| 2026-10-10 00:00 |
13:06:27.48 |
-45:20:47.1 |
HIP 63868 |
11.42 |
| 2026-10-10 12:00 |
13:06:29.31 |
-45:20:53.3 |
HIP 63868 |
11.72 |
| 2026-10-11 00:00 |
13:06:31.13 |
-45:20:59.5 |
HIP 63868 |
12.01 |