| Parameter |
Value |
| Designation |
C/2016 VZ18 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-03-07T09:07:19.603200Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:28Z |
| Obs used |
351 |
| NEO |
- |
| M1 |
18.400 |
| K1 |
9.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2017-02-20.0000000 |
| e |
0.99532240 |
| q (au) |
0.910266 |
| a (au) |
194.601204 |
| i (deg) |
24.035635 |
| Ω (om, deg) |
98.954808 |
| ω (w, deg) |
36.386221 |
| M (ma, deg) |
359.994416 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.990 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.990 |
| 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) |
| 2026-03-26 00:00 |
19:49:27.40 |
-26:50:32.3 |
HIP 97613 |
14.35 |
| 2026-03-26 12:00 |
19:49:29.66 |
-26:50:35.6 |
HIP 97613 |
13.96 |
| 2026-03-27 00:00 |
19:49:31.87 |
-26:50:39.0 |
HIP 97613 |
13.58 |
| 2026-03-27 12:00 |
19:49:34.04 |
-26:50:42.6 |
HIP 97613 |
13.22 |
| 2026-03-28 00:00 |
19:49:36.17 |
-26:50:46.3 |
HIP 97613 |
12.88 |
| 2026-03-28 12:00 |
19:49:38.25 |
-26:50:50.2 |
HIP 97613 |
12.55 |
| 2026-03-29 00:00 |
19:49:40.29 |
-26:50:54.2 |
HIP 97613 |
12.24 |
| 2026-03-29 12:00 |
19:49:42.28 |
-26:50:58.3 |
HIP 97613 |
11.95 |
| 2026-03-30 00:00 |
19:49:44.23 |
-26:51:02.5 |
HIP 97613 |
11.68 |
| 2026-03-30 12:00 |
19:49:46.14 |
-26:51:06.9 |
HIP 97613 |
11.43 |
| 2026-03-31 00:00 |
19:49:48.00 |
-26:51:11.4 |
HIP 97613 |
11.20 |
| 2026-03-31 12:00 |
19:49:49.81 |
-26:51:16.1 |
HIP 97613 |
10.99 |
| 2026-04-01 00:00 |
19:49:51.58 |
-26:51:20.9 |
HIP 97613 |
10.80 |
| 2026-04-01 12:00 |
19:49:53.30 |
-26:51:25.8 |
HIP 97613 |
10.63 |
| 2026-04-02 00:00 |
19:49:54.98 |
-26:51:30.8 |
HIP 97613 |
10.47 |
| 2026-04-02 12:00 |
19:49:56.61 |
-26:51:36.0 |
HIP 97613 |
10.34 |
| 2026-04-03 00:00 |
19:49:58.20 |
-26:51:41.3 |
HIP 97613 |
10.23 |
| 2026-04-03 12:00 |
19:49:59.74 |
-26:51:46.7 |
HIP 97613 |
10.13 |
| 2026-04-04 00:00 |
19:50:01.23 |
-26:51:52.3 |
HIP 97613 |
10.05 |
| 2026-04-04 12:00 |
19:50:02.68 |
-26:51:58.0 |
HIP 97613 |
10.00 |
| 2026-04-05 00:00 |
19:50:04.09 |
-26:52:03.8 |
HIP 97613 |
9.95 |
| 2026-04-05 12:00 |
19:50:05.44 |
-26:52:09.8 |
HIP 97613 |
9.93 |
| 2026-04-06 00:00 |
19:50:06.75 |
-26:52:15.9 |
HIP 97613 |
9.92 |
| 2026-04-06 12:00 |
19:50:08.02 |
-26:52:22.1 |
HIP 97613 |
9.92 |
| 2026-04-07 00:00 |
19:50:09.24 |
-26:52:28.5 |
HIP 97613 |
9.94 |
| 2026-04-07 12:00 |
19:50:10.41 |
-26:52:35.0 |
HIP 97613 |
9.98 |
| 2026-04-08 00:00 |
19:50:11.53 |
-26:52:41.6 |
HIP 97613 |
10.02 |
| 2026-04-08 12:00 |
19:50:12.61 |
-26:52:48.3 |
HIP 97613 |
10.08 |
| 2026-04-09 00:00 |
19:50:13.64 |
-26:52:55.2 |
HIP 97613 |
10.15 |
| 2026-04-09 12:00 |
19:50:14.63 |
-26:53:02.2 |
HIP 97613 |
10.22 |
| 2026-04-10 00:00 |
19:50:15.56 |
-26:53:09.3 |
HIP 97613 |
10.31 |
| 2026-04-10 12:00 |
19:50:16.45 |
-26:53:16.6 |
HIP 97613 |
10.40 |
| 2026-04-11 00:00 |
19:50:17.29 |
-26:53:24.0 |
HIP 97613 |
10.51 |
| 2026-04-11 12:00 |
19:50:18.09 |
-26:53:31.5 |
HIP 97613 |
10.62 |
| 2026-04-12 00:00 |
19:50:18.84 |
-26:53:39.2 |
HIP 97613 |
10.73 |
| 2026-04-12 12:00 |
19:50:19.54 |
-26:53:47.0 |
HIP 97613 |
10.85 |
| 2026-04-13 00:00 |
19:50:20.19 |
-26:53:54.9 |
HIP 97613 |
10.98 |
| 2026-04-13 12:00 |
19:50:20.79 |
-26:54:02.9 |
HIP 97613 |
11.11 |
| 2026-04-14 00:00 |
19:50:21.35 |
-26:54:11.1 |
HIP 97613 |
11.24 |
| 2026-04-14 12:00 |
19:50:21.86 |
-26:54:19.3 |
HIP 97613 |
11.38 |
| 2026-04-15 00:00 |
19:50:22.32 |
-26:54:27.8 |
HIP 97613 |
11.52 |
| 2026-04-15 12:00 |
19:50:22.74 |
-26:54:36.3 |
HIP 97613 |
11.66 |
| 2026-04-16 00:00 |
19:50:23.10 |
-26:54:45.0 |
HIP 97613 |
11.81 |