| Parameter |
Value |
| Designation |
C/2014 W9 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2015-02-15T16:56:21.163200Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:03Z |
| Obs used |
120 |
| NEO |
- |
| M1 |
14.600 |
| K1 |
13.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2015-01-29.0000000 |
| e |
0.85784434 |
| q (au) |
1.587455 |
| a (au) |
11.167021 |
| i (deg) |
10.630531 |
| Ω (om, deg) |
21.288616 |
| ω (w, deg) |
167.769440 |
| M (ma, deg) |
359.532358 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.130 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.130 |
| n |
6.000 |
| gf |
0.800 |
| gb |
-0.833 |
| k |
0.986 |
| 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) |
| 2026-09-25 00:00 |
00:01:24.47 |
-04:37:03.0 |
HIP 81 |
19.95 |
| 2026-09-25 12:00 |
00:01:18.86 |
-04:37:37.1 |
HIP 81 |
19.00 |
| 2026-09-26 00:00 |
00:01:13.26 |
-04:38:11.1 |
HIP 81 |
18.12 |
| 2026-09-26 12:00 |
00:01:07.66 |
-04:38:45.0 |
HIP 81 |
17.33 |
| 2026-09-27 00:00 |
00:01:02.07 |
-04:39:18.8 |
HIP 81 |
16.64 |
| 2026-09-27 12:00 |
00:00:56.48 |
-04:39:52.5 |
HIP 81 |
16.06 |
| 2026-09-28 00:00 |
00:00:50.89 |
-04:40:26.1 |
HIP 81 |
15.61 |
| 2026-09-28 12:00 |
00:00:45.31 |
-04:40:59.5 |
HIP 81 |
15.29 |
| 2026-09-29 00:00 |
00:00:39.73 |
-04:41:32.9 |
HIP 81 |
15.12 |
| 2026-09-29 12:00 |
00:00:34.16 |
-04:42:06.2 |
HIP 81 |
15.10 |
| 2026-09-30 00:00 |
00:00:28.60 |
-04:42:39.3 |
HIP 81 |
15.22 |
| 2026-09-30 12:00 |
00:00:23.04 |
-04:43:12.4 |
HIP 81 |
15.49 |
| 2026-10-01 00:00 |
00:00:17.49 |
-04:43:45.3 |
HIP 81 |
15.89 |
| 2026-10-01 12:00 |
00:00:11.95 |
-04:44:18.1 |
HIP 81 |
16.42 |
| 2026-10-02 00:00 |
00:00:06.42 |
-04:44:50.8 |
HIP 81 |
17.07 |
| 2026-10-02 12:00 |
00:00:00.89 |
-04:45:23.3 |
HIP 81 |
17.81 |
| 2026-10-03 00:00 |
23:59:55.37 |
-04:45:55.7 |
HIP 81 |
18.64 |
| 2026-10-03 12:00 |
23:59:49.87 |
-04:46:28.0 |
HIP 81 |
19.55 |
| 2026-10-04 00:00 |
23:59:44.37 |
-04:47:00.1 |
HIP 81 |
20.52 |
| 2026-10-04 12:00 |
23:59:38.89 |
-04:47:32.1 |
HIP 81 |
21.54 |
| 2026-10-05 00:00 |
23:59:33.41 |
-04:48:04.0 |
HIP 81 |
22.61 |
| 2026-10-05 12:00 |
23:59:27.95 |
-04:48:35.7 |
HIP 81 |
23.72 |
| 2026-10-06 00:00 |
23:59:22.50 |
-04:49:07.2 |
HIP 81 |
24.87 |
| 2026-10-06 12:00 |
23:59:17.07 |
-04:49:38.6 |
HIP 81 |
26.04 |
| 2026-10-07 00:00 |
23:59:11.65 |
-04:50:09.8 |
HIP 81 |
27.24 |
| 2026-10-07 12:00 |
23:59:06.24 |
-04:50:40.9 |
HIP 81 |
28.46 |
| 2026-10-08 00:00 |
23:59:00.84 |
-04:51:11.8 |
HIP 81 |
29.69 |
| 2026-10-08 12:00 |
23:58:55.46 |
-04:51:42.5 |
HIP 81 |
30.94 |
| 2026-10-09 00:00 |
23:58:50.10 |
-04:52:13.1 |
HIP 81 |
32.20 |
| 2026-10-09 12:00 |
23:58:44.75 |
-04:52:43.5 |
HIP 81 |
33.47 |
| 2026-10-10 00:00 |
23:58:39.42 |
-04:53:13.7 |
HIP 81 |
34.75 |
| 2026-10-10 12:00 |
23:58:34.11 |
-04:53:43.7 |
HIP 118141 |
35.52 |
| 2026-10-11 00:00 |
23:58:28.82 |
-04:54:13.5 |
HIP 118141 |
34.64 |
| 2026-10-11 12:00 |
23:58:23.54 |
-04:54:43.2 |
HIP 118141 |
33.81 |
| 2026-10-12 00:00 |
23:58:18.28 |
-04:55:12.6 |
HIP 118141 |
33.02 |
| 2026-10-12 12:00 |
23:58:13.04 |
-04:55:41.9 |
HIP 118141 |
32.27 |
| 2026-10-13 00:00 |
23:58:07.82 |
-04:56:11.0 |
HIP 118141 |
31.57 |
| 2026-10-13 12:00 |
23:58:02.62 |
-04:56:39.8 |
HIP 118141 |
30.92 |
| 2026-10-14 00:00 |
23:57:57.45 |
-04:57:08.5 |
HIP 118141 |
30.33 |
| 2026-10-14 12:00 |
23:57:52.29 |
-04:57:37.0 |
HIP 118141 |
29.79 |
| 2026-10-15 00:00 |
23:57:47.15 |
-04:58:05.2 |
HIP 118141 |
29.30 |
| 2026-10-15 12:00 |
23:57:42.04 |
-04:58:33.3 |
HIP 118141 |
28.88 |
| 2026-10-16 00:00 |
23:57:36.95 |
-04:59:01.1 |
HIP 118141 |
28.52 |