| Parameter |
Value |
| Designation |
C/2014 W11 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2015-06-17T08:54:15.324480Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:04Z |
| Obs used |
1038 |
| NEO |
- |
| M1 |
10.300 |
| K1 |
6.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2015-06-01.0000000 |
| e |
0.65023088 |
| q (au) |
3.426807 |
| a (au) |
9.797339 |
| i (deg) |
12.706625 |
| Ω (om, deg) |
295.942382 |
| ω (w, deg) |
225.644803 |
| M (ma, deg) |
359.473841 |
Magnitude
Scatter + Global Linear
$$
M_a = (7.093 + 3.562\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
7.093 |
| n |
3.562 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2014-10-22 |
2015-06-12 |
+82.2821 |
-44.843 |
| 2015-06-27 |
2017-05-27 |
+12.3719 |
-7.898 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
21:56:31.72 |
-00:39:54.2 |
HIP 108299 |
1.75 |
| 2026-05-12 12:00 |
21:56:33.61 |
-00:39:13.5 |
HIP 108299 |
2.52 |
| 2026-05-13 00:00 |
21:56:35.43 |
-00:38:32.9 |
HIP 108299 |
3.31 |
| 2026-05-13 12:00 |
21:56:37.20 |
-00:37:52.7 |
HIP 108299 |
4.09 |
| 2026-05-14 00:00 |
21:56:38.90 |
-00:37:12.7 |
HIP 108299 |
4.87 |
| 2026-05-14 12:00 |
21:56:40.55 |
-00:36:33.1 |
HIP 108299 |
5.63 |
| 2026-05-15 00:00 |
21:56:42.12 |
-00:35:53.7 |
HIP 108299 |
6.39 |
| 2026-05-15 12:00 |
21:56:43.64 |
-00:35:14.6 |
HIP 108299 |
7.13 |
| 2026-05-16 00:00 |
21:56:45.10 |
-00:34:35.8 |
HIP 108299 |
7.87 |
| 2026-05-16 12:00 |
21:56:46.49 |
-00:33:57.3 |
HIP 108299 |
8.59 |
| 2026-05-17 00:00 |
21:56:47.82 |
-00:33:19.0 |
HIP 108299 |
9.30 |
| 2026-05-17 12:00 |
21:56:49.09 |
-00:32:41.1 |
HIP 108299 |
9.99 |
| 2026-05-18 00:00 |
21:56:50.29 |
-00:32:03.5 |
HIP 108299 |
10.68 |
| 2026-05-18 12:00 |
21:56:51.43 |
-00:31:26.2 |
HIP 108299 |
11.35 |
| 2026-05-19 00:00 |
21:56:52.51 |
-00:30:49.2 |
HIP 108299 |
12.01 |
| 2026-05-19 12:00 |
21:56:53.53 |
-00:30:12.4 |
HIP 108299 |
12.67 |
| 2026-05-20 00:00 |
21:56:54.48 |
-00:29:36.0 |
HIP 108299 |
13.30 |
| 2026-05-20 12:00 |
21:56:55.37 |
-00:29:00.0 |
HIP 108299 |
13.93 |
| 2026-05-21 00:00 |
21:56:56.20 |
-00:28:24.2 |
HIP 108299 |
14.55 |
| 2026-05-21 12:00 |
21:56:56.96 |
-00:27:48.7 |
HIP 108406 |
14.86 |
| 2026-05-22 00:00 |
21:56:57.66 |
-00:27:13.6 |
HIP 108406 |
15.13 |
| 2026-05-22 12:00 |
21:56:58.30 |
-00:26:38.7 |
HIP 108406 |
15.43 |
| 2026-05-23 00:00 |
21:56:58.87 |
-00:26:04.2 |
HIP 108406 |
15.75 |
| 2026-05-23 12:00 |
21:56:59.38 |
-00:25:30.1 |
HIP 108406 |
16.10 |
| 2026-05-24 00:00 |
21:56:59.83 |
-00:24:56.2 |
HIP 108406 |
16.46 |
| 2026-05-24 12:00 |
21:57:00.21 |
-00:24:22.6 |
HIP 108406 |
16.84 |
| 2026-05-25 00:00 |
21:57:00.54 |
-00:23:49.4 |
HIP 108406 |
17.23 |
| 2026-05-25 12:00 |
21:57:00.79 |
-00:23:16.6 |
HIP 108406 |
17.64 |
| 2026-05-26 00:00 |
21:57:00.99 |
-00:22:44.0 |
HIP 108406 |
18.06 |
| 2026-05-26 12:00 |
21:57:01.12 |
-00:22:11.8 |
HIP 108406 |
18.49 |
| 2026-05-27 00:00 |
21:57:01.19 |
-00:21:39.9 |
HIP 108406 |
18.93 |
| 2026-05-27 12:00 |
21:57:01.19 |
-00:21:08.3 |
HIP 108406 |
19.38 |
| 2026-05-28 00:00 |
21:57:01.14 |
-00:20:37.1 |
HIP 108406 |
19.83 |
| 2026-05-28 12:00 |
21:57:01.02 |
-00:20:06.2 |
HIP 108406 |
20.29 |
| 2026-05-29 00:00 |
21:57:00.83 |
-00:19:35.7 |
HIP 108406 |
20.76 |
| 2026-05-29 12:00 |
21:57:00.59 |
-00:19:05.5 |
HIP 108406 |
21.23 |
| 2026-05-30 00:00 |
21:57:00.28 |
-00:18:35.6 |
HIP 108406 |
21.70 |
| 2026-05-30 12:00 |
21:56:59.90 |
-00:18:06.1 |
HIP 108406 |
22.18 |
| 2026-05-31 00:00 |
21:56:59.47 |
-00:17:37.0 |
HIP 108406 |
22.66 |
| 2026-05-31 12:00 |
21:56:58.97 |
-00:17:08.2 |
HIP 108406 |
23.15 |
| 2026-06-01 00:00 |
21:56:58.40 |
-00:16:39.7 |
HIP 108406 |
23.63 |
| 2026-06-01 12:00 |
21:56:57.78 |
-00:16:11.6 |
HIP 108406 |
24.12 |
| 2026-06-02 00:00 |
21:56:57.09 |
-00:15:43.8 |
HIP 108406 |
24.61 |