| 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) |
| 2026-09-20 00:00 |
21:38:01.01 |
-00:59:01.9 |
HIP 106817 |
13.51 |
| 2026-09-20 12:00 |
21:37:55.64 |
-00:59:38.6 |
HIP 106817 |
14.21 |
| 2026-09-21 00:00 |
21:37:50.32 |
-01:00:15.4 |
HIP 106817 |
15.03 |
| 2026-09-21 12:00 |
21:37:45.04 |
-01:00:52.1 |
HIP 106817 |
15.93 |
| 2026-09-22 00:00 |
21:37:39.81 |
-01:01:28.8 |
HIP 106817 |
16.91 |
| 2026-09-22 12:00 |
21:37:34.62 |
-01:02:05.4 |
HIP 106817 |
17.95 |
| 2026-09-23 00:00 |
21:37:29.47 |
-01:02:42.0 |
HIP 106817 |
19.03 |
| 2026-09-23 12:00 |
21:37:24.37 |
-01:03:18.5 |
HIP 106817 |
20.15 |
| 2026-09-24 00:00 |
21:37:19.32 |
-01:03:55.1 |
HIP 106817 |
21.29 |
| 2026-09-24 12:00 |
21:37:14.31 |
-01:04:31.5 |
HIP 106655 |
21.02 |
| 2026-09-25 00:00 |
21:37:09.36 |
-01:05:07.9 |
HIP 106655 |
19.69 |
| 2026-09-25 12:00 |
21:37:04.44 |
-01:05:44.3 |
HIP 106655 |
18.37 |
| 2026-09-26 00:00 |
21:36:59.58 |
-01:06:20.6 |
HIP 106655 |
17.08 |
| 2026-09-26 12:00 |
21:36:54.77 |
-01:06:56.8 |
HIP 106655 |
15.80 |
| 2026-09-27 00:00 |
21:36:50.00 |
-01:07:33.0 |
HIP 106655 |
14.55 |
| 2026-09-27 12:00 |
21:36:45.28 |
-01:08:09.0 |
HIP 106655 |
13.32 |
| 2026-09-28 00:00 |
21:36:40.61 |
-01:08:45.0 |
HIP 106655 |
12.11 |
| 2026-09-28 12:00 |
21:36:36.00 |
-01:09:21.0 |
HIP 106655 |
10.95 |
| 2026-09-29 00:00 |
21:36:31.43 |
-01:09:56.8 |
HIP 106655 |
9.82 |
| 2026-09-29 12:00 |
21:36:26.91 |
-01:10:32.6 |
HIP 106655 |
8.74 |
| 2026-09-30 00:00 |
21:36:22.45 |
-01:11:08.3 |
HIP 106655 |
7.73 |
| 2026-09-30 12:00 |
21:36:18.03 |
-01:11:43.8 |
HIP 106655 |
6.82 |
| 2026-10-01 00:00 |
21:36:13.67 |
-01:12:19.3 |
HIP 106655 |
6.03 |
| 2026-10-01 12:00 |
21:36:09.36 |
-01:12:54.7 |
HIP 106655 |
5.41 |
| 2026-10-02 00:00 |
21:36:05.11 |
-01:13:30.0 |
HIP 106655 |
5.01 |
| 2026-10-02 12:00 |
21:36:00.90 |
-01:14:05.1 |
HIP 106655 |
4.89 |
| 2026-10-03 00:00 |
21:35:56.75 |
-01:14:40.2 |
HIP 106655 |
5.06 |
| 2026-10-03 12:00 |
21:35:52.66 |
-01:15:15.1 |
HIP 106655 |
5.47 |
| 2026-10-04 00:00 |
21:35:48.62 |
-01:15:49.9 |
HIP 106655 |
6.08 |
| 2026-10-04 12:00 |
21:35:44.63 |
-01:16:24.6 |
HIP 106655 |
6.81 |
| 2026-10-05 00:00 |
21:35:40.70 |
-01:16:59.2 |
HIP 106655 |
7.64 |
| 2026-10-05 12:00 |
21:35:36.83 |
-01:17:33.6 |
HIP 106655 |
8.53 |
| 2026-10-06 00:00 |
21:35:33.01 |
-01:18:07.9 |
HIP 106655 |
9.45 |
| 2026-10-06 12:00 |
21:35:29.25 |
-01:18:42.1 |
HIP 106655 |
10.40 |
| 2026-10-07 00:00 |
21:35:25.55 |
-01:19:16.1 |
HIP 106655 |
11.36 |
| 2026-10-07 12:00 |
21:35:21.90 |
-01:19:50.0 |
HIP 106655 |
12.32 |
| 2026-10-08 00:00 |
21:35:18.31 |
-01:20:23.7 |
HIP 106655 |
13.29 |
| 2026-10-08 12:00 |
21:35:14.78 |
-01:20:57.2 |
HIP 106655 |
14.26 |
| 2026-10-09 00:00 |
21:35:11.31 |
-01:21:30.6 |
HIP 106655 |
15.22 |
| 2026-10-09 12:00 |
21:35:07.89 |
-01:22:03.9 |
HIP 106655 |
16.17 |
| 2026-10-10 00:00 |
21:35:04.54 |
-01:22:37.0 |
HIP 106655 |
17.12 |
| 2026-10-10 12:00 |
21:35:01.24 |
-01:23:09.9 |
HIP 106655 |
18.06 |
| 2026-10-11 00:00 |
21:34:58.01 |
-01:23:42.6 |
HIP 106655 |
18.98 |