| Parameter |
Value |
| Designation |
C/2016 A5 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2015-06-28T07:50:25.661760Z |
| Orbit solution date (soln_date, UTC) |
2022-07-06T03:12:22Z |
| Obs used |
46 |
| NEO |
- |
| M1 |
13.100 |
| K1 |
11.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2015-12-22.0000000 |
| e |
0.99730397 |
| q (au) |
2.947450 |
| a (au) |
1093.256056 |
| i (deg) |
40.327049 |
| Ω (om, deg) |
136.218315 |
| ω (w, deg) |
321.625267 |
| M (ma, deg) |
0.004817 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.549 + 4.558\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.549 |
| n |
4.558 |
| gf |
0.971 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
1.000 |
| 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 |
16:20:44.52 |
+17:42:42.7 |
HIP 79995 |
14.57 |
| 2026-09-20 12:00 |
16:20:46.68 |
+17:41:56.8 |
HIP 79995 |
15.31 |
| 2026-09-21 00:00 |
16:20:48.87 |
+17:41:11.1 |
HIP 79995 |
16.08 |
| 2026-09-21 12:00 |
16:20:51.09 |
+17:40:25.4 |
HIP 79995 |
16.87 |
| 2026-09-22 00:00 |
16:20:53.36 |
+17:39:39.8 |
HIP 79995 |
17.69 |
| 2026-09-22 12:00 |
16:20:55.65 |
+17:38:54.3 |
HIP 79995 |
18.52 |
| 2026-09-23 00:00 |
16:20:57.99 |
+17:38:09.0 |
HIP 79995 |
19.36 |
| 2026-09-23 12:00 |
16:21:00.36 |
+17:37:23.7 |
HIP 79995 |
20.23 |
| 2026-09-24 00:00 |
16:21:02.76 |
+17:36:38.5 |
HIP 79995 |
21.10 |
| 2026-09-24 12:00 |
16:21:05.20 |
+17:35:53.4 |
HIP 79995 |
21.99 |
| 2026-09-25 00:00 |
16:21:07.67 |
+17:35:08.4 |
HIP 79995 |
22.88 |
| 2026-09-25 12:00 |
16:21:10.18 |
+17:34:23.6 |
HIP 79995 |
23.79 |
| 2026-09-26 00:00 |
16:21:12.73 |
+17:33:38.8 |
HIP 79995 |
24.71 |
| 2026-09-26 12:00 |
16:21:15.31 |
+17:32:54.2 |
HIP 80239 |
24.86 |
| 2026-09-27 00:00 |
16:21:17.92 |
+17:32:09.7 |
HIP 80239 |
24.03 |
| 2026-09-27 12:00 |
16:21:20.56 |
+17:31:25.3 |
HIP 80239 |
23.19 |
| 2026-09-28 00:00 |
16:21:23.24 |
+17:30:41.0 |
HIP 80239 |
22.36 |
| 2026-09-28 12:00 |
16:21:25.96 |
+17:29:56.8 |
HIP 80239 |
21.54 |
| 2026-09-29 00:00 |
16:21:28.71 |
+17:29:12.8 |
HIP 80239 |
20.72 |
| 2026-09-29 12:00 |
16:21:31.49 |
+17:28:28.9 |
HIP 80239 |
19.90 |
| 2026-09-30 00:00 |
16:21:34.30 |
+17:27:45.1 |
HIP 80239 |
19.10 |
| 2026-09-30 12:00 |
16:21:37.15 |
+17:27:01.5 |
HIP 80239 |
18.31 |
| 2026-10-01 00:00 |
16:21:40.03 |
+17:26:18.0 |
HIP 80239 |
17.53 |
| 2026-10-01 12:00 |
16:21:42.94 |
+17:25:34.7 |
HIP 80239 |
16.76 |
| 2026-10-02 00:00 |
16:21:45.89 |
+17:24:51.5 |
HIP 80239 |
16.02 |
| 2026-10-02 12:00 |
16:21:48.86 |
+17:24:08.4 |
HIP 80239 |
15.29 |
| 2026-10-03 00:00 |
16:21:51.88 |
+17:23:25.5 |
HIP 80239 |
14.60 |
| 2026-10-03 12:00 |
16:21:54.92 |
+17:22:42.7 |
HIP 80239 |
13.93 |
| 2026-10-04 00:00 |
16:21:57.99 |
+17:22:00.1 |
HIP 80239 |
13.30 |
| 2026-10-04 12:00 |
16:22:01.10 |
+17:21:17.7 |
HIP 80239 |
12.71 |
| 2026-10-05 00:00 |
16:22:04.24 |
+17:20:35.4 |
HIP 80239 |
12.17 |
| 2026-10-05 12:00 |
16:22:07.41 |
+17:19:53.3 |
HIP 80239 |
11.69 |
| 2026-10-06 00:00 |
16:22:10.61 |
+17:19:11.3 |
HIP 80239 |
11.28 |
| 2026-10-06 12:00 |
16:22:13.84 |
+17:18:29.5 |
HIP 80239 |
10.94 |
| 2026-10-07 00:00 |
16:22:17.10 |
+17:17:47.9 |
HIP 80239 |
10.68 |
| 2026-10-07 12:00 |
16:22:20.40 |
+17:17:06.4 |
HIP 80239 |
10.52 |
| 2026-10-08 00:00 |
16:22:23.72 |
+17:16:25.1 |
HIP 80239 |
10.45 |
| 2026-10-08 12:00 |
16:22:27.08 |
+17:15:44.0 |
HIP 80239 |
10.48 |
| 2026-10-09 00:00 |
16:22:30.46 |
+17:15:03.1 |
HIP 80239 |
10.60 |
| 2026-10-09 12:00 |
16:22:33.88 |
+17:14:22.4 |
HIP 80239 |
10.83 |
| 2026-10-10 00:00 |
16:22:37.32 |
+17:13:41.9 |
HIP 80239 |
11.14 |
| 2026-10-10 12:00 |
16:22:40.79 |
+17:13:01.5 |
HIP 80239 |
11.54 |
| 2026-10-11 00:00 |
16:22:44.30 |
+17:12:21.4 |
HIP 80239 |
12.02 |