| Parameter |
Value |
| Designation |
311P/PANSTARRS |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2017-07-10T16:19:53.999040Z |
| Orbit solution date (soln_date, UTC) |
2025-05-08T09:42:30Z |
| Obs used |
272 |
| NEO |
- |
| M1 |
19.000 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2017-04-29.0000000 |
| e |
0.11566755 |
| q (au) |
1.935566 |
| a (au) |
2.188731 |
| i (deg) |
4.966451 |
| Ω (om, deg) |
279.259757 |
| ω (w, deg) |
143.998566 |
| M (ma, deg) |
337.877546 |
Magnitude
Scatter + Global Linear
$$
M_a = (19.434 + 2.034\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
19.434 |
| n |
2.034 |
| gf |
0.800 |
| gb |
-0.702 |
| k |
0.976 |
| δ90 |
1.000 |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
23:01:23.50 |
-02:35:52.8 |
HIP 113727 |
9.56 |
| 2026-06-01 12:00 |
23:01:59.58 |
-02:30:48.7 |
HIP 113727 |
10.40 |
| 2026-06-02 00:00 |
23:02:35.48 |
-02:25:45.1 |
HIP 113727 |
18.38 |
| 2026-06-02 12:00 |
23:03:11.21 |
-02:20:42.0 |
HIP 113727 |
27.88 |
| 2026-06-03 00:00 |
23:03:46.75 |
-02:15:39.4 |
HIP 113931 |
23.07 |
| 2026-06-03 12:00 |
23:04:22.11 |
-02:10:37.4 |
HIP 113931 |
16.66 |
| 2026-06-04 00:00 |
23:04:57.28 |
-02:05:35.9 |
HIP 113931 |
15.12 |
| 2026-06-04 12:00 |
23:05:32.27 |
-02:00:34.9 |
HIP 113931 |
19.58 |
| 2026-06-05 00:00 |
23:06:07.07 |
-01:55:34.5 |
HIP 114202 |
25.71 |
| 2026-06-05 12:00 |
23:06:41.69 |
-01:50:34.7 |
HIP 114202 |
21.54 |
| 2026-06-06 00:00 |
23:07:16.11 |
-01:45:35.5 |
HIP 114202 |
21.61 |
| 2026-06-06 12:00 |
23:07:50.34 |
-01:40:36.9 |
HIP 114202 |
25.82 |
| 2026-06-07 00:00 |
23:08:24.38 |
-01:35:38.9 |
HIP 114202 |
32.57 |
| 2026-06-07 12:00 |
23:08:58.22 |
-01:30:41.6 |
HIP 114202 |
40.58 |
| 2026-06-08 00:00 |
23:09:31.87 |
-01:25:44.9 |
HIP 114517 |
36.91 |
| 2026-06-08 12:00 |
23:10:05.32 |
-01:20:48.9 |
HIP 114517 |
27.21 |
| 2026-06-09 00:00 |
23:10:38.56 |
-01:15:53.5 |
HIP 114517 |
17.57 |
| 2026-06-09 12:00 |
23:11:11.60 |
-01:10:58.8 |
HIP 114517 |
8.02 |
| 2026-06-10 00:00 |
23:11:44.44 |
-01:06:04.9 |
HIP 114517 |
2.12 |
| 2026-06-10 12:00 |
23:12:17.07 |
-01:01:11.6 |
HIP 114517 |
11.24 |
| 2026-06-11 00:00 |
23:12:49.49 |
-00:56:19.1 |
HIP 114517 |
20.66 |
| 2026-06-11 12:00 |
23:13:21.70 |
-00:51:27.3 |
HIP 114609 |
25.72 |
| 2026-06-12 00:00 |
23:13:53.70 |
-00:46:36.3 |
HIP 114770 |
22.71 |
| 2026-06-12 12:00 |
23:14:25.48 |
-00:41:46.1 |
HIP 114770 |
22.83 |
| 2026-06-13 00:00 |
23:14:57.04 |
-00:36:56.7 |
HIP 114770 |
26.43 |
| 2026-06-13 12:00 |
23:15:28.39 |
-00:32:08.1 |
HIP 114852 |
30.18 |
| 2026-06-14 00:00 |
23:15:59.51 |
-00:27:20.3 |
HIP 114852 |
25.01 |
| 2026-06-14 12:00 |
23:16:30.41 |
-00:22:33.4 |
HIP 114852 |
22.51 |
| 2026-06-15 00:00 |
23:17:01.08 |
-00:17:47.3 |
HIP 114852 |
23.47 |
| 2026-06-15 12:00 |
23:17:31.53 |
-00:13:02.1 |
HIP 114852 |
27.50 |
| 2026-06-16 00:00 |
23:18:01.75 |
-00:08:17.8 |
HIP 114852 |
33.44 |
| 2026-06-16 12:00 |
23:18:31.73 |
-00:03:34.4 |
HIP 115190 |
31.57 |
| 2026-06-17 00:00 |
23:19:01.49 |
+00:01:08.1 |
HIP 115050 |
31.66 |
| 2026-06-17 12:00 |
23:19:31.01 |
+00:05:49.7 |
HIP 115063 |
31.16 |
| 2026-06-18 00:00 |
23:20:00.29 |
+00:10:30.4 |
HIP 115063 |
32.64 |
| 2026-06-18 12:00 |
23:20:29.33 |
+00:15:10.1 |
HIP 115063 |
36.15 |
| 2026-06-19 00:00 |
23:20:58.14 |
+00:19:48.8 |
HIP 115476 |
38.51 |
| 2026-06-19 12:00 |
23:21:26.70 |
+00:24:26.6 |
HIP 115476 |
32.07 |
| 2026-06-20 00:00 |
23:21:55.02 |
+00:29:03.3 |
HIP 115476 |
26.85 |
| 2026-06-20 12:00 |
23:22:23.09 |
+00:33:39.1 |
HIP 115476 |
23.61 |
| 2026-06-21 00:00 |
23:22:50.92 |
+00:38:13.9 |
HIP 115476 |
23.14 |
| 2026-06-21 12:00 |
23:23:18.49 |
+00:42:47.6 |
HIP 115474 |
23.48 |
| 2026-06-22 00:00 |
23:23:45.82 |
+00:47:20.3 |
HIP 115474 |
19.09 |