| 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) |
| 2026-03-26 00:00 |
21:20:12.90 |
-14:05:04.4 |
HIP 105315 |
7.13 |
| 2026-03-26 12:00 |
21:21:05.42 |
-14:00:17.6 |
HIP 105315 |
18.64 |
| 2026-03-27 00:00 |
21:21:57.84 |
-13:55:30.2 |
HIP 105315 |
31.83 |
| 2026-03-27 12:00 |
21:22:50.17 |
-13:50:42.1 |
HIP 105603 |
21.25 |
| 2026-03-28 00:00 |
21:23:42.41 |
-13:45:53.4 |
HIP 105603 |
15.96 |
| 2026-03-28 12:00 |
21:24:34.56 |
-13:41:03.9 |
HIP 105759 |
14.75 |
| 2026-03-29 00:00 |
21:25:26.62 |
-13:36:13.9 |
HIP 105759 |
7.42 |
| 2026-03-29 12:00 |
21:26:18.59 |
-13:31:23.2 |
HIP 105759 |
16.09 |
| 2026-03-30 00:00 |
21:27:10.46 |
-13:26:31.8 |
HIP 105946 |
9.26 |
| 2026-03-30 12:00 |
21:28:02.24 |
-13:21:39.8 |
HIP 105946 |
16.58 |
| 2026-03-31 00:00 |
21:28:53.94 |
-13:16:47.2 |
HIP 105946 |
28.77 |
| 2026-03-31 12:00 |
21:29:45.53 |
-13:11:54.0 |
HIP 106089 |
26.18 |
| 2026-04-01 00:00 |
21:30:37.04 |
-13:07:00.1 |
HIP 106089 |
27.44 |
| 2026-04-01 12:00 |
21:31:28.45 |
-13:02:05.7 |
HIP 106380 |
31.85 |
| 2026-04-02 00:00 |
21:32:19.78 |
-12:57:10.6 |
HIP 106380 |
31.09 |
| 2026-04-02 12:00 |
21:33:11.00 |
-12:52:15.0 |
HIP 106441 |
35.21 |
| 2026-04-03 00:00 |
21:34:02.14 |
-12:47:18.7 |
HIP 106475 |
39.09 |
| 2026-04-03 12:00 |
21:34:53.18 |
-12:42:21.9 |
HIP 106475 |
36.97 |
| 2026-04-04 00:00 |
21:35:44.13 |
-12:37:24.5 |
HIP 106475 |
39.54 |
| 2026-04-04 12:00 |
21:36:34.98 |
-12:32:26.6 |
HIP 106833 |
38.74 |
| 2026-04-05 00:00 |
21:37:25.74 |
-12:27:28.1 |
HIP 106833 |
27.71 |
| 2026-04-05 12:00 |
21:38:16.41 |
-12:22:29.0 |
HIP 106833 |
19.79 |
| 2026-04-06 00:00 |
21:39:06.98 |
-12:17:29.4 |
HIP 106833 |
19.26 |
| 2026-04-06 12:00 |
21:39:57.46 |
-12:12:29.3 |
HIP 106951 |
25.25 |
| 2026-04-07 00:00 |
21:40:47.84 |
-12:07:28.6 |
HIP 107127 |
19.27 |
| 2026-04-07 12:00 |
21:41:38.12 |
-12:02:27.4 |
HIP 107127 |
13.66 |
| 2026-04-08 00:00 |
21:42:28.31 |
-11:57:25.7 |
HIP 107182 |
5.52 |
| 2026-04-08 12:00 |
21:43:18.40 |
-11:52:23.5 |
HIP 107182 |
14.37 |
| 2026-04-09 00:00 |
21:44:08.39 |
-11:47:20.9 |
HIP 107337 |
3.92 |
| 2026-04-09 12:00 |
21:44:58.28 |
-11:42:17.7 |
HIP 107337 |
9.35 |
| 2026-04-10 00:00 |
21:45:48.08 |
-11:37:14.0 |
HIP 107527 |
14.00 |
| 2026-04-10 12:00 |
21:46:37.78 |
-11:32:09.9 |
HIP 107527 |
9.74 |
| 2026-04-11 00:00 |
21:47:27.38 |
-11:27:05.4 |
HIP 107517 |
14.49 |
| 2026-04-11 12:00 |
21:48:16.88 |
-11:22:00.3 |
HIP 107517 |
25.69 |
| 2026-04-12 00:00 |
21:49:06.28 |
-11:16:54.9 |
HIP 107793 |
16.40 |
| 2026-04-12 12:00 |
21:49:55.57 |
-11:11:49.0 |
HIP 107793 |
9.60 |
| 2026-04-13 00:00 |
21:50:44.77 |
-11:06:42.7 |
HIP 107793 |
16.10 |
| 2026-04-13 12:00 |
21:51:33.87 |
-11:01:35.9 |
HIP 107846 |
24.68 |
| 2026-04-14 00:00 |
21:52:22.86 |
-10:56:28.8 |
HIP 108018 |
24.58 |
| 2026-04-14 12:00 |
21:53:11.75 |
-10:51:21.3 |
HIP 108018 |
17.80 |
| 2026-04-15 00:00 |
21:54:00.53 |
-10:46:13.4 |
HIP 108018 |
19.23 |
| 2026-04-15 12:00 |
21:54:49.21 |
-10:41:05.1 |
HIP 108018 |
27.59 |
| 2026-04-16 00:00 |
21:55:37.79 |
-10:35:56.4 |
HIP 108058 |
34.55 |