| Parameter |
Value |
| Designation |
C/2015 WZ (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2016-04-15T19:10:55.200000Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:17Z |
| Obs used |
373 |
| NEO |
- |
| M1 |
10.400 |
| K1 |
25.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2016-05-03.0000000 |
| e |
0.99287381 |
| q (au) |
1.376638 |
| a (au) |
193.179952 |
| i (deg) |
134.134938 |
| Ω (om, deg) |
40.045810 |
| ω (w, deg) |
66.710648 |
| M (ma, deg) |
0.006314 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.676 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.676 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| k |
1.000 |
| 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) |
| 2026-07-29 00:00 |
11:38:18.16 |
-27:21:43.9 |
HIP 56838 |
22.84 |
| 2026-07-29 12:00 |
11:38:21.05 |
-27:21:35.7 |
HIP 56838 |
22.66 |
| 2026-07-30 00:00 |
11:38:23.97 |
-27:21:27.8 |
HIP 56838 |
22.49 |
| 2026-07-30 12:00 |
11:38:26.91 |
-27:21:20.2 |
HIP 56838 |
22.33 |
| 2026-07-31 00:00 |
11:38:29.89 |
-27:21:13.0 |
HIP 56838 |
22.18 |
| 2026-07-31 12:00 |
11:38:32.89 |
-27:21:06.1 |
HIP 56838 |
22.04 |
| 2026-08-01 00:00 |
11:38:35.92 |
-27:20:59.6 |
HIP 56838 |
21.92 |
| 2026-08-01 12:00 |
11:38:38.97 |
-27:20:53.4 |
HIP 56838 |
21.81 |
| 2026-08-02 00:00 |
11:38:42.05 |
-27:20:47.6 |
HIP 56838 |
21.71 |
| 2026-08-02 12:00 |
11:38:45.16 |
-27:20:42.1 |
HIP 56838 |
21.63 |
| 2026-08-03 00:00 |
11:38:48.29 |
-27:20:37.0 |
HIP 56838 |
21.56 |
| 2026-08-03 12:00 |
11:38:51.45 |
-27:20:32.2 |
HIP 56838 |
21.51 |
| 2026-08-04 00:00 |
11:38:54.63 |
-27:20:27.7 |
HIP 56838 |
21.47 |
| 2026-08-04 12:00 |
11:38:57.84 |
-27:20:23.6 |
HIP 56838 |
21.46 |
| 2026-08-05 00:00 |
11:39:01.08 |
-27:20:19.8 |
HIP 56838 |
21.46 |
| 2026-08-05 12:00 |
11:39:04.34 |
-27:20:16.4 |
HIP 56838 |
21.47 |
| 2026-08-06 00:00 |
11:39:07.62 |
-27:20:13.4 |
HIP 56838 |
21.51 |
| 2026-08-06 12:00 |
11:39:10.93 |
-27:20:10.7 |
HIP 56838 |
21.57 |
| 2026-08-07 00:00 |
11:39:14.26 |
-27:20:08.3 |
HIP 56838 |
21.64 |
| 2026-08-07 12:00 |
11:39:17.62 |
-27:20:06.3 |
HIP 56838 |
21.73 |
| 2026-08-08 00:00 |
11:39:21.00 |
-27:20:04.6 |
HIP 56838 |
21.85 |
| 2026-08-08 12:00 |
11:39:24.40 |
-27:20:03.3 |
HIP 56838 |
21.98 |
| 2026-08-09 00:00 |
11:39:27.83 |
-27:20:02.3 |
HIP 56838 |
22.14 |
| 2026-08-09 12:00 |
11:39:31.28 |
-27:20:01.6 |
HIP 56838 |
22.31 |
| 2026-08-10 00:00 |
11:39:34.75 |
-27:20:01.4 |
HIP 56838 |
22.51 |
| 2026-08-10 12:00 |
11:39:38.25 |
-27:20:01.4 |
HIP 56838 |
22.73 |
| 2026-08-11 00:00 |
11:39:41.77 |
-27:20:01.8 |
HIP 56838 |
22.96 |
| 2026-08-11 12:00 |
11:39:45.31 |
-27:20:02.6 |
HIP 56838 |
23.22 |
| 2026-08-12 00:00 |
11:39:48.87 |
-27:20:03.7 |
HIP 56838 |
23.50 |
| 2026-08-12 12:00 |
11:39:52.45 |
-27:20:05.1 |
HIP 56838 |
23.79 |
| 2026-08-13 00:00 |
11:39:56.06 |
-27:20:06.9 |
HIP 56838 |
24.11 |
| 2026-08-13 12:00 |
11:39:59.68 |
-27:20:09.1 |
HIP 56838 |
24.44 |
| 2026-08-14 00:00 |
11:40:03.33 |
-27:20:11.6 |
HIP 56838 |
24.80 |
| 2026-08-14 12:00 |
11:40:06.99 |
-27:20:14.4 |
HIP 56838 |
25.17 |
| 2026-08-15 00:00 |
11:40:10.68 |
-27:20:17.6 |
HIP 56838 |
25.56 |
| 2026-08-15 12:00 |
11:40:14.38 |
-27:20:21.1 |
HIP 56838 |
25.97 |
| 2026-08-16 00:00 |
11:40:18.10 |
-27:20:25.0 |
HIP 56838 |
26.39 |
| 2026-08-16 12:00 |
11:40:21.85 |
-27:20:29.2 |
HIP 56838 |
26.83 |
| 2026-08-17 00:00 |
11:40:25.61 |
-27:20:33.7 |
HIP 56838 |
27.29 |
| 2026-08-17 12:00 |
11:40:29.39 |
-27:20:38.6 |
HIP 56838 |
27.77 |
| 2026-08-18 00:00 |
11:40:33.19 |
-27:20:43.8 |
HIP 56838 |
28.26 |
| 2026-08-18 12:00 |
11:40:37.00 |
-27:20:49.4 |
HIP 56838 |
28.76 |
| 2026-08-19 00:00 |
11:40:40.84 |
-27:20:55.3 |
HIP 56838 |
29.28 |