| Parameter |
Value |
| Designation |
C/2020 H2 (Pruyne) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2020-04-27T14:08:36.116160Z |
| Orbit solution date (soln_date, UTC) |
2025-01-10T09:12:14Z |
| Obs used |
121 |
| NEO |
- |
| M1 |
18.900 |
| K1 |
22.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2020-05-25.0000000 |
| e |
0.99553868 |
| q (au) |
0.833616 |
| a (au) |
186.853978 |
| i (deg) |
125.044340 |
| Ω (om, deg) |
277.635070 |
| ω (w, deg) |
26.692025 |
| M (ma, deg) |
0.010577 |
Magnitude
Scatter + Global Linear
$$
M_a = (17.971 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
17.971 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.893 |
| 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 |
06:18:01.17 |
+21:39:46.6 |
HIP 29981 |
30.32 |
| 2026-05-12 12:00 |
06:18:05.91 |
+21:39:40.7 |
HIP 29981 |
29.91 |
| 2026-05-13 00:00 |
06:18:10.68 |
+21:39:34.8 |
HIP 29981 |
29.54 |
| 2026-05-13 12:00 |
06:18:15.48 |
+21:39:28.8 |
HIP 29981 |
29.21 |
| 2026-05-14 00:00 |
06:18:20.32 |
+21:39:22.8 |
HIP 29981 |
28.91 |
| 2026-05-14 12:00 |
06:18:25.19 |
+21:39:16.8 |
HIP 29981 |
28.65 |
| 2026-05-15 00:00 |
06:18:30.10 |
+21:39:10.7 |
HIP 29981 |
28.43 |
| 2026-05-15 12:00 |
06:18:35.04 |
+21:39:04.5 |
HIP 29981 |
28.26 |
| 2026-05-16 00:00 |
06:18:40.01 |
+21:38:58.4 |
HIP 29981 |
28.13 |
| 2026-05-16 12:00 |
06:18:45.02 |
+21:38:52.1 |
HIP 29981 |
28.05 |
| 2026-05-17 00:00 |
06:18:50.06 |
+21:38:45.9 |
HIP 29981 |
28.02 |
| 2026-05-17 12:00 |
06:18:55.13 |
+21:38:39.6 |
HIP 29981 |
28.04 |
| 2026-05-18 00:00 |
06:19:00.23 |
+21:38:33.3 |
HIP 29981 |
28.11 |
| 2026-05-18 12:00 |
06:19:05.36 |
+21:38:26.9 |
HIP 29981 |
28.23 |
| 2026-05-19 00:00 |
06:19:10.53 |
+21:38:20.5 |
HIP 29981 |
28.40 |
| 2026-05-19 12:00 |
06:19:15.72 |
+21:38:14.0 |
HIP 29981 |
28.63 |
| 2026-05-20 00:00 |
06:19:20.94 |
+21:38:07.5 |
HIP 29981 |
28.90 |
| 2026-05-20 12:00 |
06:19:26.19 |
+21:38:01.0 |
HIP 30075 |
28.97 |
| 2026-05-21 00:00 |
06:19:31.47 |
+21:37:54.4 |
HIP 30075 |
28.92 |
| 2026-05-21 12:00 |
06:19:36.78 |
+21:37:47.8 |
HIP 30075 |
28.92 |
| 2026-05-22 00:00 |
06:19:42.12 |
+21:37:41.2 |
HIP 30075 |
28.97 |
| 2026-05-22 12:00 |
06:19:47.48 |
+21:37:34.5 |
HIP 30075 |
29.08 |
| 2026-05-23 00:00 |
06:19:52.87 |
+21:37:27.7 |
HIP 30075 |
29.24 |
| 2026-05-23 12:00 |
06:19:58.29 |
+21:37:21.0 |
HIP 30075 |
29.45 |
| 2026-05-24 00:00 |
06:20:03.73 |
+21:37:14.1 |
HIP 30075 |
29.72 |
| 2026-05-24 12:00 |
06:20:09.20 |
+21:37:07.3 |
HIP 30075 |
30.05 |
| 2026-05-25 00:00 |
06:20:14.70 |
+21:37:00.4 |
HIP 30211 |
29.54 |
| 2026-05-25 12:00 |
06:20:20.22 |
+21:36:53.4 |
HIP 30211 |
28.78 |
| 2026-05-26 00:00 |
06:20:25.76 |
+21:36:46.4 |
HIP 30211 |
28.05 |
| 2026-05-26 12:00 |
06:20:31.33 |
+21:36:39.4 |
HIP 30211 |
27.36 |
| 2026-05-27 00:00 |
06:20:36.92 |
+21:36:32.4 |
HIP 30211 |
26.71 |
| 2026-05-27 12:00 |
06:20:42.54 |
+21:36:25.2 |
HIP 30241 |
26.11 |
| 2026-05-28 00:00 |
06:20:48.18 |
+21:36:18.1 |
HIP 30241 |
25.32 |
| 2026-05-28 12:00 |
06:20:53.84 |
+21:36:10.9 |
HIP 30241 |
24.57 |
| 2026-05-29 00:00 |
06:20:59.52 |
+21:36:03.7 |
HIP 30241 |
23.87 |
| 2026-05-29 12:00 |
06:21:05.23 |
+21:35:56.4 |
HIP 30241 |
23.22 |
| 2026-05-30 00:00 |
06:21:10.95 |
+21:35:49.1 |
HIP 30241 |
22.63 |
| 2026-05-30 12:00 |
06:21:16.70 |
+21:35:41.7 |
HIP 30241 |
22.11 |
| 2026-05-31 00:00 |
06:21:22.47 |
+21:35:34.3 |
HIP 30241 |
21.65 |
| 2026-05-31 12:00 |
06:21:28.26 |
+21:35:26.9 |
HIP 30241 |
21.26 |
| 2026-06-01 00:00 |
06:21:34.07 |
+21:35:19.4 |
HIP 30241 |
20.96 |
| 2026-06-01 12:00 |
06:21:39.90 |
+21:35:11.9 |
HIP 30241 |
20.73 |
| 2026-06-02 00:00 |
06:21:45.75 |
+21:35:04.4 |
HIP 30241 |
20.60 |