| Parameter |
Value |
| Designation |
C/1973 H1 (Huchra) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1973-03-11T12:39:25.813440Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:22Z |
| Obs used |
26 |
| NEO |
- |
| M1 |
9.300 |
| K1 |
10.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1973-05-30.0000000 |
| e |
0.97294134 |
| q (au) |
2.384240 |
| a (au) |
88.113743 |
| i (deg) |
48.329625 |
| Ω (om, deg) |
57.840302 |
| ω (w, deg) |
123.470767 |
| M (ma, deg) |
0.094701 |
Magnitude
Scatter + Global Linear
$$
M_a = (9.905 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.905 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| 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) |
| 2026-07-29 00:00 |
01:08:28.65 |
-43:44:36.4 |
HIP 5292 |
8.65 |
| 2026-07-29 12:00 |
01:08:28.04 |
-43:44:56.3 |
HIP 5292 |
8.44 |
| 2026-07-30 00:00 |
01:08:27.41 |
-43:45:16.2 |
HIP 5292 |
8.24 |
| 2026-07-30 12:00 |
01:08:26.76 |
-43:45:36.1 |
HIP 5292 |
8.04 |
| 2026-07-31 00:00 |
01:08:26.10 |
-43:45:56.0 |
HIP 5292 |
7.85 |
| 2026-07-31 12:00 |
01:08:25.42 |
-43:46:16.0 |
HIP 5292 |
7.67 |
| 2026-08-01 00:00 |
01:08:24.72 |
-43:46:35.9 |
HIP 5292 |
7.50 |
| 2026-08-01 12:00 |
01:08:24.00 |
-43:46:55.8 |
HIP 5292 |
7.34 |
| 2026-08-02 00:00 |
01:08:23.27 |
-43:47:15.7 |
HIP 5292 |
7.19 |
| 2026-08-02 12:00 |
01:08:22.52 |
-43:47:35.6 |
HIP 5292 |
7.05 |
| 2026-08-03 00:00 |
01:08:21.75 |
-43:47:55.4 |
HIP 5292 |
6.93 |
| 2026-08-03 12:00 |
01:08:20.97 |
-43:48:15.3 |
HIP 5292 |
6.82 |
| 2026-08-04 00:00 |
01:08:20.17 |
-43:48:35.2 |
HIP 5292 |
6.72 |
| 2026-08-04 12:00 |
01:08:19.35 |
-43:48:55.0 |
HIP 5292 |
6.64 |
| 2026-08-05 00:00 |
01:08:18.51 |
-43:49:14.8 |
HIP 5292 |
6.57 |
| 2026-08-05 12:00 |
01:08:17.66 |
-43:49:34.6 |
HIP 5292 |
6.52 |
| 2026-08-06 00:00 |
01:08:16.79 |
-43:49:54.4 |
HIP 5292 |
6.49 |
| 2026-08-06 12:00 |
01:08:15.90 |
-43:50:14.2 |
HIP 5292 |
6.47 |
| 2026-08-07 00:00 |
01:08:15.00 |
-43:50:33.9 |
HIP 5292 |
6.47 |
| 2026-08-07 12:00 |
01:08:14.08 |
-43:50:53.6 |
HIP 5292 |
6.50 |
| 2026-08-08 00:00 |
01:08:13.14 |
-43:51:13.3 |
HIP 5292 |
6.53 |
| 2026-08-08 12:00 |
01:08:12.19 |
-43:51:33.0 |
HIP 5292 |
6.59 |
| 2026-08-09 00:00 |
01:08:11.22 |
-43:51:52.6 |
HIP 5292 |
6.67 |
| 2026-08-09 12:00 |
01:08:10.23 |
-43:52:12.2 |
HIP 5292 |
6.76 |
| 2026-08-10 00:00 |
01:08:09.22 |
-43:52:31.8 |
HIP 5292 |
6.86 |
| 2026-08-10 12:00 |
01:08:08.20 |
-43:52:51.3 |
HIP 5292 |
6.99 |
| 2026-08-11 00:00 |
01:08:07.17 |
-43:53:10.8 |
HIP 5292 |
7.13 |
| 2026-08-11 12:00 |
01:08:06.11 |
-43:53:30.3 |
HIP 5292 |
7.28 |
| 2026-08-12 00:00 |
01:08:05.04 |
-43:53:49.7 |
HIP 5292 |
7.45 |
| 2026-08-12 12:00 |
01:08:03.96 |
-43:54:09.1 |
HIP 5292 |
7.63 |
| 2026-08-13 00:00 |
01:08:02.86 |
-43:54:28.4 |
HIP 5292 |
7.82 |
| 2026-08-13 12:00 |
01:08:01.74 |
-43:54:47.7 |
HIP 5292 |
8.03 |
| 2026-08-14 00:00 |
01:08:00.60 |
-43:55:07.0 |
HIP 5292 |
8.24 |
| 2026-08-14 12:00 |
01:07:59.45 |
-43:55:26.2 |
HIP 5292 |
8.46 |
| 2026-08-15 00:00 |
01:07:58.29 |
-43:55:45.4 |
HIP 5292 |
8.70 |
| 2026-08-15 12:00 |
01:07:57.11 |
-43:56:04.5 |
HIP 5292 |
8.94 |
| 2026-08-16 00:00 |
01:07:55.91 |
-43:56:23.5 |
HIP 5292 |
9.19 |
| 2026-08-16 12:00 |
01:07:54.70 |
-43:56:42.5 |
HIP 5292 |
9.45 |
| 2026-08-17 00:00 |
01:07:53.47 |
-43:57:01.5 |
HIP 5292 |
9.72 |
| 2026-08-17 12:00 |
01:07:52.22 |
-43:57:20.4 |
HIP 5292 |
9.99 |
| 2026-08-18 00:00 |
01:07:50.97 |
-43:57:39.2 |
HIP 5292 |
10.26 |
| 2026-08-18 12:00 |
01:07:49.69 |
-43:57:58.0 |
HIP 5292 |
10.55 |
| 2026-08-19 00:00 |
01:07:48.40 |
-43:58:16.7 |
HIP 5292 |
10.84 |