| Parameter |
Value |
| Designation |
C/2011 Q1 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2011-06-29T10:55:01.718400Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:54Z |
| Obs used |
59 |
| NEO |
- |
| M1 |
7.500 |
| K1 |
10.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2011-09-21.0000000 |
| e |
0.99791265 |
| q (au) |
6.780085 |
| a (au) |
3248.185456 |
| i (deg) |
94.862014 |
| Ω (om, deg) |
142.243907 |
| ω (w, deg) |
135.926448 |
| M (ma, deg) |
0.000445 |
Magnitude
Scatter + Global Linear
$$
M_a = (2.217 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
2.217 |
| n |
6.000 |
| gf |
0.994 |
| gb |
-0.711 |
| 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) |
| 2026-09-20 00:00 |
04:45:04.42 |
-76:41:46.3 |
HIP 22165 |
19.81 |
| 2026-09-20 12:00 |
04:45:01.82 |
-76:42:41.1 |
HIP 22165 |
18.94 |
| 2026-09-21 00:00 |
04:44:59.08 |
-76:43:35.8 |
HIP 22165 |
18.08 |
| 2026-09-21 12:00 |
04:44:56.18 |
-76:44:30.3 |
HIP 22165 |
17.23 |
| 2026-09-22 00:00 |
04:44:53.14 |
-76:45:24.6 |
HIP 22165 |
16.39 |
| 2026-09-22 12:00 |
04:44:49.94 |
-76:46:18.8 |
HIP 22165 |
15.57 |
| 2026-09-23 00:00 |
04:44:46.60 |
-76:47:12.8 |
HIP 22165 |
14.77 |
| 2026-09-23 12:00 |
04:44:43.10 |
-76:48:06.7 |
HIP 22165 |
13.98 |
| 2026-09-24 00:00 |
04:44:39.46 |
-76:49:00.3 |
HIP 22165 |
13.22 |
| 2026-09-24 12:00 |
04:44:35.66 |
-76:49:53.8 |
HIP 22165 |
12.48 |
| 2026-09-25 00:00 |
04:44:31.72 |
-76:50:47.0 |
HIP 22165 |
11.78 |
| 2026-09-25 12:00 |
04:44:27.62 |
-76:51:40.1 |
HIP 22165 |
11.11 |
| 2026-09-26 00:00 |
04:44:23.38 |
-76:52:33.0 |
HIP 22165 |
10.49 |
| 2026-09-26 12:00 |
04:44:18.98 |
-76:53:25.7 |
HIP 22165 |
9.92 |
| 2026-09-27 00:00 |
04:44:14.44 |
-76:54:18.2 |
HIP 22165 |
9.42 |
| 2026-09-27 12:00 |
04:44:09.74 |
-76:55:10.4 |
HIP 22165 |
8.98 |
| 2026-09-28 00:00 |
04:44:04.90 |
-76:56:02.5 |
HIP 22165 |
8.63 |
| 2026-09-28 12:00 |
04:43:59.90 |
-76:56:54.3 |
HIP 22165 |
8.37 |
| 2026-09-29 00:00 |
04:43:54.76 |
-76:57:45.9 |
HIP 22165 |
8.22 |
| 2026-09-29 12:00 |
04:43:49.46 |
-76:58:37.2 |
HIP 22165 |
8.17 |
| 2026-09-30 00:00 |
04:43:44.02 |
-76:59:28.4 |
HIP 22165 |
8.23 |
| 2026-09-30 12:00 |
04:43:38.43 |
-77:00:19.3 |
HIP 22165 |
8.40 |
| 2026-10-01 00:00 |
04:43:32.68 |
-77:01:09.9 |
HIP 22165 |
8.66 |
| 2026-10-01 12:00 |
04:43:26.79 |
-77:02:00.4 |
HIP 22165 |
9.02 |
| 2026-10-02 00:00 |
04:43:20.75 |
-77:02:50.5 |
HIP 22165 |
9.45 |
| 2026-10-02 12:00 |
04:43:14.55 |
-77:03:40.4 |
HIP 22165 |
9.96 |
| 2026-10-03 00:00 |
04:43:08.21 |
-77:04:30.1 |
HIP 22165 |
10.53 |
| 2026-10-03 12:00 |
04:43:01.72 |
-77:05:19.4 |
HIP 22165 |
11.14 |
| 2026-10-04 00:00 |
04:42:55.08 |
-77:06:08.6 |
HIP 22165 |
11.80 |
| 2026-10-04 12:00 |
04:42:48.29 |
-77:06:57.4 |
HIP 22165 |
12.49 |
| 2026-10-05 00:00 |
04:42:41.36 |
-77:07:46.0 |
HIP 22165 |
13.21 |
| 2026-10-05 12:00 |
04:42:34.27 |
-77:08:34.2 |
HIP 22165 |
13.95 |
| 2026-10-06 00:00 |
04:42:27.03 |
-77:09:22.2 |
HIP 22165 |
14.72 |
| 2026-10-06 12:00 |
04:42:19.65 |
-77:10:09.9 |
HIP 22165 |
15.50 |
| 2026-10-07 00:00 |
04:42:12.12 |
-77:10:57.3 |
HIP 22165 |
16.30 |
| 2026-10-07 12:00 |
04:42:04.45 |
-77:11:44.4 |
HIP 22165 |
17.11 |
| 2026-10-08 00:00 |
04:41:56.62 |
-77:12:31.2 |
HIP 22165 |
17.93 |
| 2026-10-08 12:00 |
04:41:48.65 |
-77:13:17.7 |
HIP 22165 |
18.76 |
| 2026-10-09 00:00 |
04:41:40.54 |
-77:14:03.8 |
HIP 22165 |
19.60 |
| 2026-10-09 12:00 |
04:41:32.28 |
-77:14:49.7 |
HIP 22165 |
20.44 |
| 2026-10-10 00:00 |
04:41:23.87 |
-77:15:35.2 |
HIP 22165 |
21.29 |
| 2026-10-10 12:00 |
04:41:15.32 |
-77:16:20.4 |
HIP 22165 |
22.14 |
| 2026-10-11 00:00 |
04:41:06.63 |
-77:17:05.2 |
HIP 22165 |
23.00 |