| Parameter |
Value |
| Designation |
C/2022 Y1 (Hogan) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2022-11-27T05:12:59.653440Z |
| Orbit solution date (soln_date, UTC) |
2023-06-01T23:12:56Z |
| Obs used |
117 |
| NEO |
- |
| M1 |
13.300 |
| K1 |
10.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2022-12-17T10:28:21.676800Z |
| Discovery magnitude (MPC) |
19.72 G |
| Discovery observatory (MPC) |
G96 · Mt. Lemmon Survey |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2023-01-04.0000000 |
| e |
0.76423431 |
| q (au) |
2.957709 |
| a (au) |
12.545122 |
| i (deg) |
18.858872 |
| Ω (om, deg) |
285.915047 |
| ω (w, deg) |
174.737499 |
| M (ma, deg) |
0.838077 |
Magnitude
Scatter + Global Linear
$$
M_a = (18.661 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
18.661 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.739 |
| 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) |
| 2026-05-12 00:00 |
14:25:04.90 |
-33:57:15.5 |
HIP 70407 |
10.48 |
| 2026-05-12 12:00 |
14:24:53.24 |
-33:56:05.2 |
HIP 70407 |
7.96 |
| 2026-05-13 00:00 |
14:24:41.64 |
-33:54:54.5 |
HIP 70407 |
5.60 |
| 2026-05-13 12:00 |
14:24:30.07 |
-33:53:43.2 |
HIP 70407 |
3.71 |
| 2026-05-14 00:00 |
14:24:18.56 |
-33:52:31.5 |
HIP 70407 |
3.26 |
| 2026-05-14 12:00 |
14:24:07.09 |
-33:51:19.3 |
HIP 70407 |
4.66 |
| 2026-05-15 00:00 |
14:23:55.67 |
-33:50:06.6 |
HIP 70407 |
6.86 |
| 2026-05-15 12:00 |
14:23:44.31 |
-33:48:53.5 |
HIP 70407 |
9.31 |
| 2026-05-16 00:00 |
14:23:33.00 |
-33:47:40.0 |
HIP 70407 |
11.84 |
| 2026-05-16 12:00 |
14:23:21.75 |
-33:46:26.0 |
HIP 70407 |
14.41 |
| 2026-05-17 00:00 |
14:23:10.55 |
-33:45:11.6 |
HIP 70407 |
17.00 |
| 2026-05-17 12:00 |
14:22:59.41 |
-33:43:56.8 |
HIP 70407 |
19.59 |
| 2026-05-18 00:00 |
14:22:48.33 |
-33:42:41.6 |
HIP 70407 |
22.19 |
| 2026-05-18 12:00 |
14:22:37.31 |
-33:41:26.0 |
HIP 70407 |
24.79 |
| 2026-05-19 00:00 |
14:22:26.35 |
-33:40:10.1 |
HIP 70407 |
27.38 |
| 2026-05-19 12:00 |
14:22:15.45 |
-33:38:53.7 |
HIP 70407 |
29.97 |
| 2026-05-20 00:00 |
14:22:04.62 |
-33:37:37.0 |
HIP 70407 |
32.55 |
| 2026-05-20 12:00 |
14:21:53.86 |
-33:36:20.0 |
HIP 70407 |
35.13 |
| 2026-05-21 00:00 |
14:21:43.16 |
-33:35:02.6 |
HIP 70407 |
37.70 |
| 2026-05-21 12:00 |
14:21:32.53 |
-33:33:44.9 |
HIP 70407 |
40.26 |
| 2026-05-22 00:00 |
14:21:21.98 |
-33:32:26.9 |
HIP 69904 |
41.87 |
| 2026-05-22 12:00 |
14:21:11.49 |
-33:31:08.6 |
HIP 69904 |
39.33 |
| 2026-05-23 00:00 |
14:21:01.07 |
-33:29:49.9 |
HIP 69904 |
36.80 |
| 2026-05-23 12:00 |
14:20:50.73 |
-33:28:31.0 |
HIP 69904 |
34.28 |
| 2026-05-24 00:00 |
14:20:40.46 |
-33:27:11.8 |
HIP 69904 |
31.78 |
| 2026-05-24 12:00 |
14:20:30.27 |
-33:25:52.4 |
HIP 69904 |
29.29 |
| 2026-05-25 00:00 |
14:20:20.16 |
-33:24:32.6 |
HIP 69904 |
26.81 |
| 2026-05-25 12:00 |
14:20:10.12 |
-33:23:12.7 |
HIP 69904 |
24.35 |
| 2026-05-26 00:00 |
14:20:00.16 |
-33:21:52.5 |
HIP 69904 |
21.91 |
| 2026-05-26 12:00 |
14:19:50.28 |
-33:20:32.0 |
HIP 69904 |
19.49 |
| 2026-05-27 00:00 |
14:19:40.48 |
-33:19:11.4 |
HIP 69904 |
17.10 |
| 2026-05-27 12:00 |
14:19:30.76 |
-33:17:50.5 |
HIP 69904 |
14.74 |
| 2026-05-28 00:00 |
14:19:21.12 |
-33:16:29.5 |
HIP 69904 |
12.42 |
| 2026-05-28 12:00 |
14:19:11.57 |
-33:15:08.2 |
HIP 69904 |
10.17 |
| 2026-05-29 00:00 |
14:19:02.10 |
-33:13:46.8 |
HIP 69904 |
8.03 |
| 2026-05-29 12:00 |
14:18:52.72 |
-33:12:25.2 |
HIP 69904 |
6.10 |
| 2026-05-30 00:00 |
14:18:43.42 |
-33:11:03.4 |
HIP 69904 |
4.64 |
| 2026-05-30 12:00 |
14:18:34.21 |
-33:09:41.5 |
HIP 69904 |
4.15 |
| 2026-05-31 00:00 |
14:18:25.09 |
-33:08:19.5 |
HIP 69902 |
4.66 |
| 2026-05-31 12:00 |
14:18:16.06 |
-33:06:57.3 |
HIP 69902 |
3.54 |
| 2026-06-01 00:00 |
14:18:07.11 |
-33:05:35.0 |
HIP 69902 |
3.76 |
| 2026-06-01 12:00 |
14:17:58.26 |
-33:04:12.6 |
HIP 69902 |
5.13 |
| 2026-06-02 00:00 |
14:17:49.50 |
-33:02:50.0 |
HIP 69902 |
7.00 |