| Parameter |
Value |
| Designation |
C/2019 A5 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2019-06-09T10:42:31.567680Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:51Z |
| Obs used |
70 |
| NEO |
- |
| M1 |
7.300 |
| K1 |
12.750 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-01-13T11:48:30.528000Z |
| Discovery magnitude (MPC) |
21.50 w |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2019-08-06.0000000 |
| e |
0.70787404 |
| q (au) |
6.324147 |
| a (au) |
21.648700 |
| i (deg) |
67.539002 |
| Ω (om, deg) |
146.619252 |
| ω (w, deg) |
356.039843 |
| M (ma, deg) |
0.563158 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.399 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.399 |
| n |
6.000 |
| gf |
0.988 |
| gb |
-0.862 |
| 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) |
| 2026-09-20 00:00 |
17:50:26.70 |
+39:06:44.7 |
HIP 87168 |
24.05 |
| 2026-09-20 12:00 |
17:50:28.97 |
+39:04:41.8 |
HIP 87168 |
25.40 |
| 2026-09-21 00:00 |
17:50:31.32 |
+39:02:39.0 |
HIP 87168 |
26.86 |
| 2026-09-21 12:00 |
17:50:33.77 |
+39:00:36.3 |
HIP 87504 |
27.48 |
| 2026-09-22 00:00 |
17:50:36.29 |
+38:58:33.7 |
HIP 87463 |
26.11 |
| 2026-09-22 12:00 |
17:50:38.91 |
+38:56:31.1 |
HIP 87463 |
24.40 |
| 2026-09-23 00:00 |
17:50:41.60 |
+38:54:28.7 |
HIP 87463 |
22.74 |
| 2026-09-23 12:00 |
17:50:44.39 |
+38:52:26.4 |
HIP 87463 |
21.14 |
| 2026-09-24 00:00 |
17:50:47.26 |
+38:50:24.2 |
HIP 87463 |
19.63 |
| 2026-09-24 12:00 |
17:50:50.21 |
+38:48:22.2 |
HIP 87463 |
18.23 |
| 2026-09-25 00:00 |
17:50:53.25 |
+38:46:20.3 |
HIP 87463 |
16.96 |
| 2026-09-25 12:00 |
17:50:56.37 |
+38:44:18.5 |
HIP 87463 |
15.85 |
| 2026-09-26 00:00 |
17:50:59.57 |
+38:42:16.9 |
HIP 87463 |
14.95 |
| 2026-09-26 12:00 |
17:51:02.86 |
+38:40:15.4 |
HIP 87371 |
13.74 |
| 2026-09-27 00:00 |
17:51:06.23 |
+38:38:14.1 |
HIP 87371 |
11.69 |
| 2026-09-27 12:00 |
17:51:09.68 |
+38:36:13.0 |
HIP 87371 |
9.67 |
| 2026-09-28 00:00 |
17:51:13.22 |
+38:34:12.0 |
HIP 87371 |
7.72 |
| 2026-09-28 12:00 |
17:51:16.84 |
+38:32:11.2 |
HIP 87371 |
5.91 |
| 2026-09-29 00:00 |
17:51:20.54 |
+38:30:10.7 |
HIP 87371 |
4.41 |
| 2026-09-29 12:00 |
17:51:24.32 |
+38:28:10.3 |
HIP 87371 |
3.62 |
| 2026-09-30 00:00 |
17:51:28.19 |
+38:26:10.1 |
HIP 87371 |
4.02 |
| 2026-09-30 12:00 |
17:51:32.13 |
+38:24:10.1 |
HIP 87371 |
5.34 |
| 2026-10-01 00:00 |
17:51:36.16 |
+38:22:10.3 |
HIP 87371 |
7.08 |
| 2026-10-01 12:00 |
17:51:40.27 |
+38:20:10.8 |
HIP 87371 |
9.01 |
| 2026-10-02 00:00 |
17:51:44.46 |
+38:18:11.5 |
HIP 87371 |
11.03 |
| 2026-10-02 12:00 |
17:51:48.73 |
+38:16:12.4 |
HIP 87371 |
13.10 |
| 2026-10-03 00:00 |
17:51:53.08 |
+38:14:13.6 |
HIP 87371 |
15.19 |
| 2026-10-03 12:00 |
17:51:57.51 |
+38:12:15.0 |
HIP 87371 |
17.31 |
| 2026-10-04 00:00 |
17:52:02.02 |
+38:10:16.7 |
HIP 87371 |
19.45 |
| 2026-10-04 12:00 |
17:52:06.61 |
+38:08:18.6 |
HIP 87371 |
21.59 |
| 2026-10-05 00:00 |
17:52:11.28 |
+38:06:20.8 |
HIP 87371 |
23.74 |
| 2026-10-05 12:00 |
17:52:16.03 |
+38:04:23.3 |
HIP 87371 |
25.90 |
| 2026-10-06 00:00 |
17:52:20.86 |
+38:02:26.1 |
HIP 87349 |
26.30 |
| 2026-10-06 12:00 |
17:52:25.76 |
+38:00:29.1 |
HIP 87349 |
25.52 |
| 2026-10-07 00:00 |
17:52:30.74 |
+37:58:32.5 |
HIP 87349 |
24.91 |
| 2026-10-07 12:00 |
17:52:35.81 |
+37:56:36.1 |
HIP 87349 |
24.50 |
| 2026-10-08 00:00 |
17:52:40.94 |
+37:54:40.1 |
HIP 87349 |
24.29 |
| 2026-10-08 12:00 |
17:52:46.16 |
+37:52:44.4 |
HIP 87349 |
24.30 |
| 2026-10-09 00:00 |
17:52:51.45 |
+37:50:49.1 |
HIP 87349 |
24.52 |
| 2026-10-09 12:00 |
17:52:56.82 |
+37:48:54.0 |
HIP 87349 |
24.95 |
| 2026-10-10 00:00 |
17:53:02.27 |
+37:46:59.3 |
HIP 87349 |
25.57 |
| 2026-10-10 12:00 |
17:53:07.79 |
+37:45:05.0 |
HIP 87349 |
26.38 |
| 2026-10-11 00:00 |
17:53:13.39 |
+37:43:11.0 |
HIP 87506 |
26.65 |