C/1968 H1 (Tago-Honda-Yamamoto)
| Parameter |
Value |
| Designation |
C/1968 H1 (Tago-Honda-Yamamoto) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1968-05-16T06:29:47.762880Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:17Z |
| Obs used |
35 |
| NEO |
- |
| M1 |
9.800 |
| K1 |
10.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1968-05-17.0000000 |
| e |
0.99621615 |
| q (au) |
0.680377 |
| a (au) |
179.810794 |
| i (deg) |
102.170261 |
| Ω (om, deg) |
233.108209 |
| ω (w, deg) |
50.446716 |
| M (ma, deg) |
0.000298 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.114 + 2.389\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.114 |
| n |
2.389 |
| gf |
0.800 |
| gb |
-1.000 |
| k |
0.800 |
| δ90 |
1.000 |
| 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) |
| 2026-02-03 00:00 |
03:26:48.40 |
-22:36:25.3 |
HIP 16010 |
19.65 |
| 2026-02-03 12:00 |
03:26:48.11 |
-22:36:11.7 |
HIP 16010 |
19.82 |
| 2026-02-04 00:00 |
03:26:47.84 |
-22:35:58.0 |
HIP 16010 |
20.00 |
| 2026-02-04 12:00 |
03:26:47.58 |
-22:35:44.2 |
HIP 16010 |
20.18 |
| 2026-02-05 00:00 |
03:26:47.34 |
-22:35:30.4 |
HIP 16010 |
20.37 |
| 2026-02-05 12:00 |
03:26:47.11 |
-22:35:16.5 |
HIP 16010 |
20.56 |
| 2026-02-06 00:00 |
03:26:46.89 |
-22:35:02.5 |
HIP 16010 |
20.75 |
| 2026-02-06 12:00 |
03:26:46.69 |
-22:34:48.6 |
HIP 16010 |
20.95 |
| 2026-02-07 00:00 |
03:26:46.50 |
-22:34:34.5 |
HIP 16010 |
21.14 |
| 2026-02-07 12:00 |
03:26:46.32 |
-22:34:20.5 |
HIP 16010 |
21.34 |
| 2026-02-08 00:00 |
03:26:46.16 |
-22:34:06.3 |
HIP 16010 |
21.55 |
| 2026-02-08 12:00 |
03:26:46.01 |
-22:33:52.2 |
HIP 16010 |
21.75 |
| 2026-02-09 00:00 |
03:26:45.88 |
-22:33:37.9 |
HIP 16010 |
21.96 |
| 2026-02-09 12:00 |
03:26:45.75 |
-22:33:23.7 |
HIP 16010 |
22.17 |
| 2026-02-10 00:00 |
03:26:45.65 |
-22:33:09.4 |
HIP 16010 |
22.39 |
| 2026-02-10 12:00 |
03:26:45.55 |
-22:32:55.0 |
HIP 16010 |
22.60 |
| 2026-02-11 00:00 |
03:26:45.47 |
-22:32:40.7 |
HIP 16010 |
22.82 |
| 2026-02-11 12:00 |
03:26:45.41 |
-22:32:26.2 |
HIP 16010 |
23.04 |
| 2026-02-12 00:00 |
03:26:45.36 |
-22:32:11.8 |
HIP 16010 |
23.26 |
| 2026-02-12 12:00 |
03:26:45.32 |
-22:31:57.3 |
HIP 16010 |
23.48 |
| 2026-02-13 00:00 |
03:26:45.29 |
-22:31:42.7 |
HIP 16010 |
23.71 |
| 2026-02-13 12:00 |
03:26:45.28 |
-22:31:28.2 |
HIP 16006 |
23.49 |
| 2026-02-14 00:00 |
03:26:45.29 |
-22:31:13.6 |
HIP 16006 |
23.26 |
| 2026-02-14 12:00 |
03:26:45.30 |
-22:30:58.9 |
HIP 16006 |
23.04 |
| 2026-02-15 00:00 |
03:26:45.34 |
-22:30:44.3 |
HIP 16006 |
22.81 |
| 2026-02-15 12:00 |
03:26:45.38 |
-22:30:29.6 |
HIP 16006 |
22.59 |
| 2026-02-16 00:00 |
03:26:45.44 |
-22:30:14.8 |
HIP 16006 |
22.37 |
| 2026-02-16 12:00 |
03:26:45.51 |
-22:30:00.1 |
HIP 16006 |
22.15 |
| 2026-02-17 00:00 |
03:26:45.60 |
-22:29:45.3 |
HIP 16006 |
21.93 |
| 2026-02-17 12:00 |
03:26:45.70 |
-22:29:30.5 |
HIP 16006 |
21.72 |
| 2026-02-18 00:00 |
03:26:45.81 |
-22:29:15.7 |
HIP 16006 |
21.50 |
| 2026-02-18 12:00 |
03:26:45.94 |
-22:29:00.8 |
HIP 16006 |
21.29 |
| 2026-02-19 00:00 |
03:26:46.08 |
-22:28:45.9 |
HIP 16006 |
21.08 |
| 2026-02-19 12:00 |
03:26:46.24 |
-22:28:31.1 |
HIP 16006 |
20.87 |
| 2026-02-20 00:00 |
03:26:46.40 |
-22:28:16.1 |
HIP 16006 |
20.66 |
| 2026-02-20 12:00 |
03:26:46.59 |
-22:28:01.2 |
HIP 16006 |
20.45 |
| 2026-02-21 00:00 |
03:26:46.78 |
-22:27:46.3 |
HIP 16006 |
20.25 |
| 2026-02-21 12:00 |
03:26:46.99 |
-22:27:31.3 |
HIP 16006 |
20.05 |
| 2026-02-22 00:00 |
03:26:47.21 |
-22:27:16.3 |
HIP 16006 |
19.85 |
| 2026-02-22 12:00 |
03:26:47.45 |
-22:27:01.4 |
HIP 16006 |
19.66 |
| 2026-02-23 00:00 |
03:26:47.70 |
-22:26:46.4 |
HIP 16006 |
19.46 |
| 2026-02-23 12:00 |
03:26:47.96 |
-22:26:31.4 |
HIP 16006 |
19.27 |
| 2026-02-24 00:00 |
03:26:48.24 |
-22:26:16.4 |
HIP 16006 |
19.09 |