| 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 |
0.977 |
| 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) |
| 2026-07-29 00:00 |
07:04:04.05 |
+14:18:05.6 |
HIP 33997 |
12.25 |
| 2026-07-29 12:00 |
07:04:13.71 |
+14:17:43.1 |
HIP 34162 |
12.34 |
| 2026-07-30 00:00 |
07:04:23.35 |
+14:17:20.5 |
HIP 34162 |
10.02 |
| 2026-07-30 12:00 |
07:04:32.97 |
+14:16:57.7 |
HIP 34162 |
7.72 |
| 2026-07-31 00:00 |
07:04:42.56 |
+14:16:34.8 |
HIP 34162 |
5.49 |
| 2026-07-31 12:00 |
07:04:52.13 |
+14:16:11.8 |
HIP 34162 |
3.43 |
| 2026-08-01 00:00 |
07:05:01.68 |
+14:15:48.6 |
HIP 34162 |
2.11 |
| 2026-08-01 12:00 |
07:05:11.20 |
+14:15:25.4 |
HIP 34162 |
2.85 |
| 2026-08-02 00:00 |
07:05:20.70 |
+14:15:02.0 |
HIP 34162 |
4.76 |
| 2026-08-02 12:00 |
07:05:30.17 |
+14:14:38.5 |
HIP 34162 |
6.93 |
| 2026-08-03 00:00 |
07:05:39.62 |
+14:14:14.8 |
HIP 34162 |
9.17 |
| 2026-08-03 12:00 |
07:05:49.04 |
+14:13:51.0 |
HIP 34162 |
11.44 |
| 2026-08-04 00:00 |
07:05:58.44 |
+14:13:27.1 |
HIP 34162 |
13.71 |
| 2026-08-04 12:00 |
07:06:07.80 |
+14:13:03.1 |
HIP 34258 |
13.92 |
| 2026-08-05 00:00 |
07:06:17.15 |
+14:12:39.0 |
HIP 34258 |
13.82 |
| 2026-08-05 12:00 |
07:06:26.46 |
+14:12:14.7 |
HIP 34258 |
14.09 |
| 2026-08-06 00:00 |
07:06:35.75 |
+14:11:50.4 |
HIP 34258 |
14.71 |
| 2026-08-06 12:00 |
07:06:45.00 |
+14:11:25.9 |
HIP 34376 |
15.32 |
| 2026-08-07 00:00 |
07:06:54.23 |
+14:11:01.3 |
HIP 34376 |
13.86 |
| 2026-08-07 12:00 |
07:07:03.43 |
+14:10:36.6 |
HIP 34376 |
12.66 |
| 2026-08-08 00:00 |
07:07:12.60 |
+14:10:11.7 |
HIP 34376 |
11.78 |
| 2026-08-08 12:00 |
07:07:21.74 |
+14:09:46.8 |
HIP 34376 |
11.29 |
| 2026-08-09 00:00 |
07:07:30.85 |
+14:09:21.8 |
HIP 34376 |
11.25 |
| 2026-08-09 12:00 |
07:07:39.92 |
+14:08:56.6 |
HIP 34376 |
11.65 |
| 2026-08-10 00:00 |
07:07:48.97 |
+14:08:31.3 |
HIP 34376 |
12.44 |
| 2026-08-10 12:00 |
07:07:57.98 |
+14:08:06.0 |
HIP 34376 |
13.56 |
| 2026-08-11 00:00 |
07:08:06.96 |
+14:07:40.5 |
HIP 34376 |
14.92 |
| 2026-08-11 12:00 |
07:08:15.91 |
+14:07:14.9 |
HIP 34376 |
16.47 |
| 2026-08-12 00:00 |
07:08:24.82 |
+14:06:49.2 |
HIP 34376 |
18.15 |
| 2026-08-12 12:00 |
07:08:33.70 |
+14:06:23.5 |
HIP 34376 |
19.93 |
| 2026-08-13 00:00 |
07:08:42.54 |
+14:05:57.6 |
HIP 34376 |
21.78 |
| 2026-08-13 12:00 |
07:08:51.35 |
+14:05:31.6 |
HIP 34376 |
23.68 |
| 2026-08-14 00:00 |
07:09:00.13 |
+14:05:05.5 |
HIP 34376 |
25.62 |
| 2026-08-14 12:00 |
07:09:08.86 |
+14:04:39.4 |
HIP 34557 |
26.03 |
| 2026-08-15 00:00 |
07:09:17.56 |
+14:04:13.1 |
HIP 34557 |
25.23 |
| 2026-08-15 12:00 |
07:09:26.23 |
+14:03:46.8 |
HIP 34557 |
24.59 |
| 2026-08-16 00:00 |
07:09:34.85 |
+14:03:20.4 |
HIP 34557 |
24.13 |
| 2026-08-16 12:00 |
07:09:43.44 |
+14:02:53.9 |
HIP 34557 |
23.85 |
| 2026-08-17 00:00 |
07:09:51.99 |
+14:02:27.3 |
HIP 34557 |
23.75 |
| 2026-08-17 12:00 |
07:10:00.50 |
+14:02:00.6 |
HIP 34557 |
23.84 |
| 2026-08-18 00:00 |
07:10:08.97 |
+14:01:33.8 |
HIP 34557 |
24.11 |
| 2026-08-18 12:00 |
07:10:17.40 |
+14:01:07.0 |
HIP 34557 |
24.55 |
| 2026-08-19 00:00 |
07:10:25.80 |
+14:00:40.0 |
HIP 34557 |
25.15 |