| 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) |
| 2026-06-01 00:00 |
01:07:39.75 |
-43:12:19.4 |
HIP 5400 |
19.91 |
| 2026-06-01 12:00 |
01:07:41.11 |
-43:12:30.2 |
HIP 5400 |
19.82 |
| 2026-06-02 00:00 |
01:07:42.46 |
-43:12:41.1 |
HIP 5400 |
19.75 |
| 2026-06-02 12:00 |
01:07:43.80 |
-43:12:52.2 |
HIP 5400 |
19.68 |
| 2026-06-03 00:00 |
01:07:45.12 |
-43:13:03.4 |
HIP 5400 |
19.62 |
| 2026-06-03 12:00 |
01:07:46.43 |
-43:13:14.7 |
HIP 5400 |
19.57 |
| 2026-06-04 00:00 |
01:07:47.72 |
-43:13:26.2 |
HIP 5400 |
19.52 |
| 2026-06-04 12:00 |
01:07:49.00 |
-43:13:37.8 |
HIP 5400 |
19.49 |
| 2026-06-05 00:00 |
01:07:50.26 |
-43:13:49.5 |
HIP 5400 |
19.46 |
| 2026-06-05 12:00 |
01:07:51.51 |
-43:14:01.4 |
HIP 5400 |
19.44 |
| 2026-06-06 00:00 |
01:07:52.74 |
-43:14:13.5 |
HIP 5400 |
19.43 |
| 2026-06-06 12:00 |
01:07:53.96 |
-43:14:25.6 |
HIP 5400 |
19.43 |
| 2026-06-07 00:00 |
01:07:55.17 |
-43:14:37.9 |
HIP 5400 |
19.43 |
| 2026-06-07 12:00 |
01:07:56.36 |
-43:14:50.3 |
HIP 5400 |
19.44 |
| 2026-06-08 00:00 |
01:07:57.54 |
-43:15:02.9 |
HIP 5400 |
19.47 |
| 2026-06-08 12:00 |
01:07:58.70 |
-43:15:15.6 |
HIP 5400 |
19.50 |
| 2026-06-09 00:00 |
01:07:59.84 |
-43:15:28.4 |
HIP 5400 |
19.53 |
| 2026-06-09 12:00 |
01:08:00.97 |
-43:15:41.3 |
HIP 5400 |
19.58 |
| 2026-06-10 00:00 |
01:08:02.09 |
-43:15:54.4 |
HIP 5400 |
19.63 |
| 2026-06-10 12:00 |
01:08:03.19 |
-43:16:07.6 |
HIP 5400 |
19.69 |
| 2026-06-11 00:00 |
01:08:04.27 |
-43:16:20.9 |
HIP 5400 |
19.76 |
| 2026-06-11 12:00 |
01:08:05.34 |
-43:16:34.4 |
HIP 5400 |
19.83 |
| 2026-06-12 00:00 |
01:08:06.39 |
-43:16:48.0 |
HIP 5400 |
19.92 |
| 2026-06-12 12:00 |
01:08:07.43 |
-43:17:01.7 |
HIP 5400 |
20.01 |
| 2026-06-13 00:00 |
01:08:08.45 |
-43:17:15.5 |
HIP 5400 |
20.11 |
| 2026-06-13 12:00 |
01:08:09.46 |
-43:17:29.5 |
HIP 5400 |
20.21 |
| 2026-06-14 00:00 |
01:08:10.45 |
-43:17:43.6 |
HIP 5400 |
20.32 |
| 2026-06-14 12:00 |
01:08:11.42 |
-43:17:57.8 |
HIP 5400 |
20.44 |
| 2026-06-15 00:00 |
01:08:12.38 |
-43:18:12.1 |
HIP 5400 |
20.57 |
| 2026-06-15 12:00 |
01:08:13.32 |
-43:18:26.5 |
HIP 5400 |
20.70 |
| 2026-06-16 00:00 |
01:08:14.25 |
-43:18:41.1 |
HIP 5400 |
20.84 |
| 2026-06-16 12:00 |
01:08:15.16 |
-43:18:55.7 |
HIP 5400 |
20.98 |
| 2026-06-17 00:00 |
01:08:16.05 |
-43:19:10.5 |
HIP 5400 |
21.14 |
| 2026-06-17 12:00 |
01:08:16.92 |
-43:19:25.4 |
HIP 5400 |
21.29 |
| 2026-06-18 00:00 |
01:08:17.78 |
-43:19:40.4 |
HIP 5400 |
21.46 |
| 2026-06-18 12:00 |
01:08:18.63 |
-43:19:55.5 |
HIP 5400 |
21.62 |
| 2026-06-19 00:00 |
01:08:19.45 |
-43:20:10.8 |
HIP 5400 |
21.80 |
| 2026-06-19 12:00 |
01:08:20.26 |
-43:20:26.1 |
HIP 5400 |
21.98 |
| 2026-06-20 00:00 |
01:08:21.05 |
-43:20:41.5 |
HIP 5400 |
22.16 |
| 2026-06-20 12:00 |
01:08:21.83 |
-43:20:57.1 |
HIP 5400 |
22.35 |
| 2026-06-21 00:00 |
01:08:22.59 |
-43:21:12.7 |
HIP 5400 |
22.55 |
| 2026-06-21 12:00 |
01:08:23.33 |
-43:21:28.5 |
HIP 5400 |
22.75 |
| 2026-06-22 00:00 |
01:08:24.06 |
-43:21:44.4 |
HIP 5400 |
22.95 |