| Parameter |
Value |
| Designation |
C/2011 U3 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2012-06-03T21:30:23.644800Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:56Z |
| Obs used |
60 |
| NEO |
- |
| M1 |
11.800 |
| K1 |
14.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2011-11-08.0000000 |
| e |
1.00044923 |
| q (au) |
1.071437 |
| a (au) |
-2385.059256 |
| i (deg) |
116.775956 |
| Ω (om, deg) |
228.378920 |
| ω (w, deg) |
287.823893 |
| M (ma, deg) |
-0.001768 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.812 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.812 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.917 |
| k |
0.999 |
| 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 |
12:54:55.77 |
+66:30:34.6 |
HIP 62839 |
14.82 |
| 2026-07-29 12:00 |
12:54:58.64 |
+66:29:46.5 |
HIP 62839 |
15.39 |
| 2026-07-30 00:00 |
12:55:01.57 |
+66:28:58.5 |
HIP 62839 |
16.00 |
| 2026-07-30 12:00 |
12:55:04.57 |
+66:28:10.6 |
HIP 62839 |
16.62 |
| 2026-07-31 00:00 |
12:55:07.63 |
+66:27:22.8 |
HIP 62839 |
17.27 |
| 2026-07-31 12:00 |
12:55:10.75 |
+66:26:35.2 |
HIP 62839 |
17.95 |
| 2026-08-01 00:00 |
12:55:13.93 |
+66:25:47.6 |
HIP 62839 |
18.64 |
| 2026-08-01 12:00 |
12:55:17.17 |
+66:25:00.2 |
HIP 62839 |
19.35 |
| 2026-08-02 00:00 |
12:55:20.47 |
+66:24:13.0 |
HIP 62839 |
20.07 |
| 2026-08-02 12:00 |
12:55:23.83 |
+66:23:25.8 |
HIP 62839 |
20.81 |
| 2026-08-03 00:00 |
12:55:27.25 |
+66:22:38.9 |
HIP 62839 |
21.56 |
| 2026-08-03 12:00 |
12:55:30.73 |
+66:21:52.0 |
HIP 62839 |
22.32 |
| 2026-08-04 00:00 |
12:55:34.27 |
+66:21:05.3 |
HIP 63152 |
22.05 |
| 2026-08-04 12:00 |
12:55:37.86 |
+66:20:18.7 |
HIP 63152 |
21.21 |
| 2026-08-05 00:00 |
12:55:41.52 |
+66:19:32.3 |
HIP 63152 |
20.37 |
| 2026-08-05 12:00 |
12:55:45.23 |
+66:18:46.1 |
HIP 63152 |
19.54 |
| 2026-08-06 00:00 |
12:55:49.00 |
+66:18:00.0 |
HIP 63152 |
18.71 |
| 2026-08-06 12:00 |
12:55:52.83 |
+66:17:14.0 |
HIP 63152 |
17.88 |
| 2026-08-07 00:00 |
12:55:56.72 |
+66:16:28.2 |
HIP 63152 |
17.06 |
| 2026-08-07 12:00 |
12:56:00.66 |
+66:15:42.6 |
HIP 63152 |
16.25 |
| 2026-08-08 00:00 |
12:56:04.66 |
+66:14:57.1 |
HIP 63152 |
15.44 |
| 2026-08-08 12:00 |
12:56:08.72 |
+66:14:11.8 |
HIP 63152 |
14.64 |
| 2026-08-09 00:00 |
12:56:12.83 |
+66:13:26.7 |
HIP 63152 |
13.84 |
| 2026-08-09 12:00 |
12:56:17.00 |
+66:12:41.8 |
HIP 63152 |
13.06 |
| 2026-08-10 00:00 |
12:56:21.23 |
+66:11:57.0 |
HIP 63152 |
12.29 |
| 2026-08-10 12:00 |
12:56:25.51 |
+66:11:12.4 |
HIP 63152 |
11.54 |
| 2026-08-11 00:00 |
12:56:29.84 |
+66:10:28.1 |
HIP 63152 |
10.81 |
| 2026-08-11 12:00 |
12:56:34.23 |
+66:09:43.9 |
HIP 63152 |
10.10 |
| 2026-08-12 00:00 |
12:56:38.67 |
+66:08:59.9 |
HIP 63152 |
9.42 |
| 2026-08-12 12:00 |
12:56:43.17 |
+66:08:16.0 |
HIP 63152 |
8.78 |
| 2026-08-13 00:00 |
12:56:47.71 |
+66:07:32.4 |
HIP 63152 |
8.18 |
| 2026-08-13 12:00 |
12:56:52.32 |
+66:06:49.0 |
HIP 63152 |
7.64 |
| 2026-08-14 00:00 |
12:56:56.97 |
+66:06:05.8 |
HIP 63152 |
7.16 |
| 2026-08-14 12:00 |
12:57:01.68 |
+66:05:22.8 |
HIP 63152 |
6.77 |
| 2026-08-15 00:00 |
12:57:06.43 |
+66:04:40.1 |
HIP 63152 |
6.48 |
| 2026-08-15 12:00 |
12:57:11.24 |
+66:03:57.5 |
HIP 63152 |
6.30 |
| 2026-08-16 00:00 |
12:57:16.10 |
+66:03:15.1 |
HIP 63152 |
6.24 |
| 2026-08-16 12:00 |
12:57:21.01 |
+66:02:33.0 |
HIP 63152 |
6.30 |
| 2026-08-17 00:00 |
12:57:25.97 |
+66:01:51.1 |
HIP 63152 |
6.49 |
| 2026-08-17 12:00 |
12:57:30.98 |
+66:01:09.4 |
HIP 63152 |
6.78 |
| 2026-08-18 00:00 |
12:57:36.04 |
+66:00:28.0 |
HIP 63152 |
7.18 |
| 2026-08-18 12:00 |
12:57:41.15 |
+65:59:46.8 |
HIP 63152 |
7.65 |
| 2026-08-19 00:00 |
12:57:46.31 |
+65:59:05.8 |
HIP 63152 |
8.20 |