C/2019 G4 (PANSTARRS)
| Parameter |
Value |
| Designation |
C/2019 G4 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2018-09-16T16:19:43.942080Z |
| Orbit solution date (soln_date, UTC) |
2023-04-24T19:06:38Z |
| Obs used |
7 |
| NEO |
- |
| M1 |
13.800 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2020-01-04.0000000 |
| e |
1.00013440 |
| q (au) |
5.864733 |
| a (au) |
-43634.843792 |
| i (deg) |
138.390694 |
| Ω (om, deg) |
130.459931 |
| ω (w, deg) |
287.998779 |
| M (ma, deg) |
0.000051 |
Magnitude
Scatter + Global Linear
$$
M_a = (4.578 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
4.578 |
| n |
6.000 |
| gf |
0.861 |
| gb |
-0.985 |
| k |
1.000 |
| δ90 |
3.283 |
| 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) |
| 2026-02-03 00:00 |
06:50:02.56 |
+47:37:28.5 |
HIP 32900 |
13.12 |
| 2026-02-03 12:00 |
06:49:52.00 |
+47:37:24.6 |
HIP 32900 |
14.87 |
| 2026-02-04 00:00 |
06:49:41.50 |
+47:37:20.2 |
HIP 32900 |
16.62 |
| 2026-02-04 12:00 |
06:49:31.06 |
+47:37:15.4 |
HIP 32900 |
18.36 |
| 2026-02-05 00:00 |
06:49:20.68 |
+47:37:10.2 |
HIP 32900 |
20.10 |
| 2026-02-05 12:00 |
06:49:10.37 |
+47:37:04.6 |
HIP 32900 |
21.83 |
| 2026-02-06 00:00 |
06:49:00.11 |
+47:36:58.5 |
HIP 32900 |
23.55 |
| 2026-02-06 12:00 |
06:48:49.92 |
+47:36:52.1 |
HIP 32588 |
25.03 |
| 2026-02-07 00:00 |
06:48:39.80 |
+47:36:45.2 |
HIP 32588 |
24.59 |
| 2026-02-07 12:00 |
06:48:29.73 |
+47:36:37.9 |
HIP 32588 |
24.27 |
| 2026-02-08 00:00 |
06:48:19.74 |
+47:36:30.2 |
HIP 32588 |
24.08 |
| 2026-02-08 12:00 |
06:48:09.81 |
+47:36:22.2 |
HIP 32588 |
24.02 |
| 2026-02-09 00:00 |
06:47:59.94 |
+47:36:13.7 |
HIP 32588 |
24.07 |
| 2026-02-09 12:00 |
06:47:50.15 |
+47:36:04.8 |
HIP 32588 |
24.25 |
| 2026-02-10 00:00 |
06:47:40.42 |
+47:35:55.5 |
HIP 32588 |
24.54 |
| 2026-02-10 12:00 |
06:47:30.76 |
+47:35:45.9 |
HIP 32588 |
24.94 |
| 2026-02-11 00:00 |
06:47:21.17 |
+47:35:35.8 |
HIP 32588 |
25.44 |
| 2026-02-11 12:00 |
06:47:11.65 |
+47:35:25.4 |
HIP 32588 |
26.04 |
| 2026-02-12 00:00 |
06:47:02.20 |
+47:35:14.6 |
HIP 32588 |
26.72 |
| 2026-02-12 12:00 |
06:46:52.83 |
+47:35:03.4 |
HIP 32588 |
27.48 |
| 2026-02-13 00:00 |
06:46:43.52 |
+47:34:51.9 |
HIP 32588 |
28.31 |
| 2026-02-13 12:00 |
06:46:34.29 |
+47:34:40.0 |
HIP 32588 |
29.19 |
| 2026-02-14 00:00 |
06:46:25.14 |
+47:34:27.7 |
HIP 32588 |
30.14 |
| 2026-02-14 12:00 |
06:46:16.05 |
+47:34:15.1 |
HIP 32588 |
31.13 |
| 2026-02-15 00:00 |
06:46:07.04 |
+47:34:02.1 |
HIP 32373 |
30.84 |
| 2026-02-15 12:00 |
06:45:58.11 |
+47:33:48.8 |
HIP 32373 |
30.31 |
| 2026-02-16 00:00 |
06:45:49.26 |
+47:33:35.1 |
HIP 32373 |
29.84 |
| 2026-02-16 12:00 |
06:45:40.48 |
+47:33:21.0 |
HIP 32373 |
29.44 |
| 2026-02-17 00:00 |
06:45:31.77 |
+47:33:06.6 |
HIP 32373 |
29.11 |
| 2026-02-17 12:00 |
06:45:23.15 |
+47:32:51.9 |
HIP 32373 |
28.84 |
| 2026-02-18 00:00 |
06:45:14.60 |
+47:32:36.9 |
HIP 32135 |
28.44 |
| 2026-02-18 12:00 |
06:45:06.13 |
+47:32:21.5 |
HIP 32135 |
27.26 |
| 2026-02-19 00:00 |
06:44:57.75 |
+47:32:05.8 |
HIP 32135 |
26.11 |
| 2026-02-19 12:00 |
06:44:49.44 |
+47:31:49.8 |
HIP 32135 |
25.01 |
| 2026-02-20 00:00 |
06:44:41.21 |
+47:31:33.4 |
HIP 32135 |
23.96 |
| 2026-02-20 12:00 |
06:44:33.06 |
+47:31:16.8 |
HIP 32135 |
22.96 |
| 2026-02-21 00:00 |
06:44:25.00 |
+47:30:59.8 |
HIP 32135 |
22.01 |
| 2026-02-21 12:00 |
06:44:17.02 |
+47:30:42.5 |
HIP 32135 |
21.13 |
| 2026-02-22 00:00 |
06:44:09.11 |
+47:30:24.9 |
HIP 32135 |
20.32 |
| 2026-02-22 12:00 |
06:44:01.30 |
+47:30:07.1 |
HIP 32135 |
19.58 |
| 2026-02-23 00:00 |
06:43:53.56 |
+47:29:48.9 |
HIP 32135 |
18.92 |
| 2026-02-23 12:00 |
06:43:45.91 |
+47:29:30.4 |
HIP 32135 |
18.35 |
| 2026-02-24 00:00 |
06:43:38.34 |
+47:29:11.7 |
HIP 32135 |
17.87 |