| Parameter |
Value |
| Designation |
C/2015 V4 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2016-08-27T23:52:13.535040Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:16Z |
| Obs used |
79 |
| NEO |
- |
| M1 |
12.900 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2016-03-18.0000000 |
| e |
0.70560176 |
| q (au) |
5.459628 |
| a (au) |
18.545043 |
| i (deg) |
60.751306 |
| Ω (om, deg) |
179.896328 |
| ω (w, deg) |
306.907117 |
| M (ma, deg) |
357.988428 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.198 + 4.797\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.198 |
| n |
4.797 |
| 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 |
17:10:32.21 |
+36:58:21.9 |
HIP 83979 |
10.11 |
| 2026-03-26 12:00 |
17:10:31.30 |
+36:59:53.7 |
HIP 83979 |
11.26 |
| 2026-03-27 00:00 |
17:10:30.32 |
+37:01:25.3 |
HIP 83979 |
12.48 |
| 2026-03-27 12:00 |
17:10:29.27 |
+37:02:56.7 |
HIP 83979 |
13.75 |
| 2026-03-28 00:00 |
17:10:28.14 |
+37:04:28.0 |
HIP 83979 |
15.07 |
| 2026-03-28 12:00 |
17:10:26.94 |
+37:05:59.0 |
HIP 84074 |
14.50 |
| 2026-03-29 00:00 |
17:10:25.67 |
+37:07:29.9 |
HIP 84074 |
13.68 |
| 2026-03-29 12:00 |
17:10:24.32 |
+37:09:00.6 |
HIP 84074 |
13.00 |
| 2026-03-30 00:00 |
17:10:22.91 |
+37:10:31.0 |
HIP 84074 |
12.49 |
| 2026-03-30 12:00 |
17:10:21.42 |
+37:12:01.3 |
HIP 84074 |
12.17 |
| 2026-03-31 00:00 |
17:10:19.85 |
+37:13:31.3 |
HIP 84074 |
12.05 |
| 2026-03-31 12:00 |
17:10:18.22 |
+37:15:01.1 |
HIP 84074 |
12.14 |
| 2026-04-01 00:00 |
17:10:16.51 |
+37:16:30.6 |
HIP 84074 |
12.43 |
| 2026-04-01 12:00 |
17:10:14.73 |
+37:17:59.9 |
HIP 84074 |
12.92 |
| 2026-04-02 00:00 |
17:10:12.88 |
+37:19:28.9 |
HIP 84074 |
13.57 |
| 2026-04-02 12:00 |
17:10:10.96 |
+37:20:57.7 |
HIP 84074 |
14.37 |
| 2026-04-03 00:00 |
17:10:08.97 |
+37:22:26.3 |
HIP 84074 |
15.29 |
| 2026-04-03 12:00 |
17:10:06.91 |
+37:23:54.5 |
HIP 84074 |
16.31 |
| 2026-04-04 00:00 |
17:10:04.77 |
+37:25:22.5 |
HIP 84074 |
17.41 |
| 2026-04-04 12:00 |
17:10:02.57 |
+37:26:50.2 |
HIP 84074 |
18.59 |
| 2026-04-05 00:00 |
17:10:00.29 |
+37:28:17.6 |
HIP 84074 |
19.81 |
| 2026-04-05 12:00 |
17:09:57.95 |
+37:29:44.7 |
HIP 84074 |
21.09 |
| 2026-04-06 00:00 |
17:09:55.53 |
+37:31:11.5 |
HIP 84074 |
22.40 |
| 2026-04-06 12:00 |
17:09:53.05 |
+37:32:38.1 |
HIP 83860 |
23.24 |
| 2026-04-07 00:00 |
17:09:50.50 |
+37:34:04.2 |
HIP 83860 |
21.98 |
| 2026-04-07 12:00 |
17:09:47.87 |
+37:35:30.1 |
HIP 83860 |
20.75 |
| 2026-04-08 00:00 |
17:09:45.18 |
+37:36:55.6 |
HIP 83860 |
19.54 |
| 2026-04-08 12:00 |
17:09:42.42 |
+37:38:20.8 |
HIP 83860 |
18.38 |
| 2026-04-09 00:00 |
17:09:39.59 |
+37:39:45.7 |
HIP 83860 |
17.26 |
| 2026-04-09 12:00 |
17:09:36.69 |
+37:41:10.2 |
HIP 83860 |
16.19 |
| 2026-04-10 00:00 |
17:09:33.72 |
+37:42:34.3 |
HIP 83860 |
15.19 |
| 2026-04-10 12:00 |
17:09:30.68 |
+37:43:58.1 |
HIP 83860 |
14.28 |
| 2026-04-11 00:00 |
17:09:27.58 |
+37:45:21.5 |
HIP 83860 |
13.46 |
| 2026-04-11 12:00 |
17:09:24.41 |
+37:46:44.6 |
HIP 83860 |
12.75 |
| 2026-04-12 00:00 |
17:09:21.17 |
+37:48:07.2 |
HIP 83860 |
12.18 |
| 2026-04-12 12:00 |
17:09:17.87 |
+37:49:29.5 |
HIP 83860 |
11.77 |
| 2026-04-13 00:00 |
17:09:14.50 |
+37:50:51.3 |
HIP 83860 |
11.53 |
| 2026-04-13 12:00 |
17:09:11.06 |
+37:52:12.8 |
HIP 83860 |
11.47 |
| 2026-04-14 00:00 |
17:09:07.56 |
+37:53:33.8 |
HIP 83860 |
11.60 |
| 2026-04-14 12:00 |
17:09:03.99 |
+37:54:54.5 |
HIP 83860 |
11.91 |
| 2026-04-15 00:00 |
17:09:00.36 |
+37:56:14.7 |
HIP 83860 |
12.38 |
| 2026-04-15 12:00 |
17:08:56.66 |
+37:57:34.4 |
HIP 83860 |
13.00 |
| 2026-04-16 00:00 |
17:08:52.89 |
+37:58:53.8 |
HIP 83860 |
13.75 |