| Parameter |
Value |
| Designation |
C/2011 P2 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2010-09-13T12:20:43.287360Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:54Z |
| Obs used |
58 |
| NEO |
- |
| M1 |
6.700 |
| K1 |
12.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2012-02-09.0000000 |
| e |
0.36981923 |
| q (au) |
6.148105 |
| a (au) |
9.756097 |
| i (deg) |
8.989636 |
| Ω (om, deg) |
204.018525 |
| ω (w, deg) |
76.384633 |
| M (ma, deg) |
16.608031 |
Magnitude
Scatter + Global Linear
$$
M_a = (3.498 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
3.498 |
| n |
6.000 |
| gf |
0.973 |
| gb |
-1.000 |
| 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 |
06:31:46.83 |
+14:22:03.5 |
HIP 30975 |
25.90 |
| 2026-03-26 12:00 |
06:31:48.35 |
+14:22:21.6 |
HIP 30975 |
26.15 |
| 2026-03-27 00:00 |
06:31:49.94 |
+14:22:39.7 |
HIP 30975 |
26.44 |
| 2026-03-27 12:00 |
06:31:51.60 |
+14:22:57.7 |
HIP 30975 |
26.74 |
| 2026-03-28 00:00 |
06:31:53.35 |
+14:23:15.6 |
HIP 30975 |
27.07 |
| 2026-03-28 12:00 |
06:31:55.17 |
+14:23:33.4 |
HIP 30975 |
27.43 |
| 2026-03-29 00:00 |
06:31:57.06 |
+14:23:51.1 |
HIP 30975 |
27.81 |
| 2026-03-29 12:00 |
06:31:59.04 |
+14:24:08.8 |
HIP 31277 |
27.81 |
| 2026-03-30 00:00 |
06:32:01.09 |
+14:24:26.3 |
HIP 31277 |
27.55 |
| 2026-03-30 12:00 |
06:32:03.21 |
+14:24:43.8 |
HIP 31306 |
27.20 |
| 2026-03-31 00:00 |
06:32:05.42 |
+14:25:01.1 |
HIP 31306 |
26.64 |
| 2026-03-31 12:00 |
06:32:07.70 |
+14:25:18.4 |
HIP 31306 |
26.05 |
| 2026-04-01 00:00 |
06:32:10.05 |
+14:25:35.6 |
HIP 31306 |
25.46 |
| 2026-04-01 12:00 |
06:32:12.48 |
+14:25:52.7 |
HIP 31306 |
24.84 |
| 2026-04-02 00:00 |
06:32:14.98 |
+14:26:09.7 |
HIP 31306 |
24.21 |
| 2026-04-02 12:00 |
06:32:17.56 |
+14:26:26.6 |
HIP 31306 |
23.57 |
| 2026-04-03 00:00 |
06:32:20.21 |
+14:26:43.3 |
HIP 31306 |
22.91 |
| 2026-04-03 12:00 |
06:32:22.94 |
+14:27:00.0 |
HIP 31306 |
22.23 |
| 2026-04-04 00:00 |
06:32:25.74 |
+14:27:16.6 |
HIP 31306 |
21.54 |
| 2026-04-04 12:00 |
06:32:28.62 |
+14:27:33.1 |
HIP 31306 |
20.83 |
| 2026-04-05 00:00 |
06:32:31.57 |
+14:27:49.5 |
HIP 31306 |
20.11 |
| 2026-04-05 12:00 |
06:32:34.59 |
+14:28:05.7 |
HIP 31306 |
19.37 |
| 2026-04-06 00:00 |
06:32:37.69 |
+14:28:21.9 |
HIP 31306 |
18.62 |
| 2026-04-06 12:00 |
06:32:40.86 |
+14:28:38.0 |
HIP 31306 |
17.86 |
| 2026-04-07 00:00 |
06:32:44.10 |
+14:28:53.9 |
HIP 31306 |
17.08 |
| 2026-04-07 12:00 |
06:32:47.42 |
+14:29:09.7 |
HIP 31306 |
16.29 |
| 2026-04-08 00:00 |
06:32:50.81 |
+14:29:25.5 |
HIP 31306 |
15.49 |
| 2026-04-08 12:00 |
06:32:54.27 |
+14:29:41.1 |
HIP 31306 |
14.67 |
| 2026-04-09 00:00 |
06:32:57.80 |
+14:29:56.6 |
HIP 31306 |
13.85 |
| 2026-04-09 12:00 |
06:33:01.41 |
+14:30:11.9 |
HIP 31306 |
13.02 |
| 2026-04-10 00:00 |
06:33:05.08 |
+14:30:27.2 |
HIP 31306 |
12.18 |
| 2026-04-10 12:00 |
06:33:08.83 |
+14:30:42.3 |
HIP 31306 |
11.34 |
| 2026-04-11 00:00 |
06:33:12.65 |
+14:30:57.3 |
HIP 31306 |
10.50 |
| 2026-04-11 12:00 |
06:33:16.54 |
+14:31:12.2 |
HIP 31306 |
9.67 |
| 2026-04-12 00:00 |
06:33:20.50 |
+14:31:27.0 |
HIP 31306 |
8.84 |
| 2026-04-12 12:00 |
06:33:24.54 |
+14:31:41.7 |
HIP 31306 |
8.04 |
| 2026-04-13 00:00 |
06:33:28.64 |
+14:31:56.2 |
HIP 31306 |
7.27 |
| 2026-04-13 12:00 |
06:33:32.81 |
+14:32:10.6 |
HIP 31306 |
6.56 |
| 2026-04-14 00:00 |
06:33:37.05 |
+14:32:24.8 |
HIP 31306 |
5.93 |
| 2026-04-14 12:00 |
06:33:41.36 |
+14:32:39.0 |
HIP 31306 |
5.42 |
| 2026-04-15 00:00 |
06:33:45.74 |
+14:32:53.0 |
HIP 31306 |
5.08 |
| 2026-04-15 12:00 |
06:33:50.19 |
+14:33:06.9 |
HIP 31306 |
4.95 |
| 2026-04-16 00:00 |
06:33:54.71 |
+14:33:20.6 |
HIP 31306 |
5.06 |