| Parameter |
Value |
| Designation |
C/1954 Y1 (Haro-Chavira) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1956-01-26T17:36:40.613760Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:12Z |
| Obs used |
57 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1956-08-14.0000000 |
| e |
1.00460292 |
| q (au) |
4.076984 |
| a (au) |
-885.738904 |
| i (deg) |
79.600837 |
| Ω (om, deg) |
72.875012 |
| ω (w, deg) |
57.309578 |
| M (ma, deg) |
0.007488 |
Magnitude
Scatter + Global Linear
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| 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) |
| 2026-05-12 00:00 |
16:59:02.22 |
-55:24:34.2 |
HIP 83201 |
20.87 |
| 2026-05-12 12:00 |
16:59:00.20 |
-55:24:37.7 |
HIP 83201 |
21.06 |
| 2026-05-13 00:00 |
16:58:58.17 |
-55:24:41.2 |
HIP 83201 |
21.26 |
| 2026-05-13 12:00 |
16:58:56.13 |
-55:24:44.5 |
HIP 83201 |
21.46 |
| 2026-05-14 00:00 |
16:58:54.09 |
-55:24:47.8 |
HIP 83201 |
21.65 |
| 2026-05-14 12:00 |
16:58:52.03 |
-55:24:51.0 |
HIP 83201 |
21.85 |
| 2026-05-15 00:00 |
16:58:49.97 |
-55:24:54.1 |
HIP 83201 |
22.05 |
| 2026-05-15 12:00 |
16:58:47.90 |
-55:24:57.1 |
HIP 83201 |
22.26 |
| 2026-05-16 00:00 |
16:58:45.83 |
-55:25:00.0 |
HIP 83201 |
22.46 |
| 2026-05-16 12:00 |
16:58:43.74 |
-55:25:02.8 |
HIP 83201 |
22.67 |
| 2026-05-17 00:00 |
16:58:41.65 |
-55:25:05.6 |
HIP 83201 |
22.87 |
| 2026-05-17 12:00 |
16:58:39.56 |
-55:25:08.2 |
HIP 83201 |
23.08 |
| 2026-05-18 00:00 |
16:58:37.45 |
-55:25:10.8 |
HIP 83201 |
23.29 |
| 2026-05-18 12:00 |
16:58:35.34 |
-55:25:13.2 |
HIP 83201 |
23.50 |
| 2026-05-19 00:00 |
16:58:33.23 |
-55:25:15.6 |
HIP 83201 |
23.72 |
| 2026-05-19 12:00 |
16:58:31.11 |
-55:25:17.9 |
HIP 83201 |
23.93 |
| 2026-05-20 00:00 |
16:58:28.98 |
-55:25:20.0 |
HIP 83201 |
24.14 |
| 2026-05-20 12:00 |
16:58:26.84 |
-55:25:22.1 |
HIP 83201 |
24.36 |
| 2026-05-21 00:00 |
16:58:24.70 |
-55:25:24.2 |
HIP 83201 |
24.58 |
| 2026-05-21 12:00 |
16:58:22.56 |
-55:25:26.1 |
HIP 83201 |
24.80 |
| 2026-05-22 00:00 |
16:58:20.41 |
-55:25:27.9 |
HIP 83201 |
25.02 |
| 2026-05-22 12:00 |
16:58:18.25 |
-55:25:29.6 |
HIP 83201 |
25.24 |
| 2026-05-23 00:00 |
16:58:16.09 |
-55:25:31.3 |
HIP 83201 |
25.46 |
| 2026-05-23 12:00 |
16:58:13.93 |
-55:25:32.8 |
HIP 83201 |
25.68 |
| 2026-05-24 00:00 |
16:58:11.76 |
-55:25:34.3 |
HIP 83201 |
25.91 |
| 2026-05-24 12:00 |
16:58:09.59 |
-55:25:35.6 |
HIP 82991 |
26.00 |
| 2026-05-25 00:00 |
16:58:07.41 |
-55:25:36.9 |
HIP 82991 |
25.92 |
| 2026-05-25 12:00 |
16:58:05.23 |
-55:25:38.1 |
HIP 82991 |
25.85 |
| 2026-05-26 00:00 |
16:58:03.04 |
-55:25:39.2 |
HIP 82991 |
25.78 |
| 2026-05-26 12:00 |
16:58:00.85 |
-55:25:40.2 |
HIP 82991 |
25.71 |
| 2026-05-27 00:00 |
16:57:58.66 |
-55:25:41.1 |
HIP 82991 |
25.65 |
| 2026-05-27 12:00 |
16:57:56.47 |
-55:25:41.9 |
HIP 82991 |
25.60 |
| 2026-05-28 00:00 |
16:57:54.27 |
-55:25:42.6 |
HIP 82991 |
25.55 |
| 2026-05-28 12:00 |
16:57:52.06 |
-55:25:43.2 |
HIP 82991 |
25.51 |
| 2026-05-29 00:00 |
16:57:49.86 |
-55:25:43.8 |
HIP 82991 |
25.47 |
| 2026-05-29 12:00 |
16:57:47.65 |
-55:25:44.2 |
HIP 82991 |
25.44 |
| 2026-05-30 00:00 |
16:57:45.44 |
-55:25:44.6 |
HIP 82991 |
25.41 |
| 2026-05-30 12:00 |
16:57:43.23 |
-55:25:44.9 |
HIP 82991 |
25.39 |
| 2026-05-31 00:00 |
16:57:41.01 |
-55:25:45.0 |
HIP 82991 |
25.37 |
| 2026-05-31 12:00 |
16:57:38.80 |
-55:25:45.1 |
HIP 82991 |
25.36 |
| 2026-06-01 00:00 |
16:57:36.58 |
-55:25:45.1 |
HIP 82991 |
25.36 |
| 2026-06-01 12:00 |
16:57:34.36 |
-55:25:45.0 |
HIP 82991 |
25.36 |
| 2026-06-02 00:00 |
16:57:32.13 |
-55:25:44.8 |
HIP 82991 |
25.36 |