| Parameter |
Value |
| Designation |
311P/PANSTARRS |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2017-07-10T15:30:22.055040Z |
| Orbit solution date (soln_date, UTC) |
2026-07-28T14:12:27Z |
| Obs used |
278 |
| NEO |
- |
| M1 |
19.100 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2017-07-27.0000000 |
| e |
0.11564657 |
| q (au) |
1.935578 |
| a (au) |
2.188693 |
| i (deg) |
4.966582 |
| Ω (om, deg) |
279.258024 |
| ω (w, deg) |
143.986827 |
| M (ma, deg) |
4.977927 |
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) |
| 2026-07-29 00:00 |
23:42:58.80 |
+05:14:49.7 |
HIP 116917 |
22.99 |
| 2026-07-29 12:00 |
23:43:00.15 |
+05:17:10.7 |
HIP 116917 |
24.98 |
| 2026-07-30 00:00 |
23:43:01.07 |
+05:19:29.1 |
HIP 116862 |
26.57 |
| 2026-07-30 12:00 |
23:43:01.55 |
+05:21:44.8 |
HIP 116862 |
27.31 |
| 2026-07-31 00:00 |
23:43:01.59 |
+05:23:57.9 |
HIP 116862 |
28.10 |
| 2026-07-31 12:00 |
23:43:01.18 |
+05:26:08.3 |
HIP 116862 |
28.92 |
| 2026-08-01 00:00 |
23:43:00.33 |
+05:28:15.9 |
HIP 116862 |
29.76 |
| 2026-08-01 12:00 |
23:42:59.02 |
+05:30:20.8 |
HIP 116862 |
30.60 |
| 2026-08-02 00:00 |
23:42:57.27 |
+05:32:22.9 |
HIP 116862 |
31.45 |
| 2026-08-02 12:00 |
23:42:55.07 |
+05:34:22.3 |
HIP 116862 |
32.29 |
| 2026-08-03 00:00 |
23:42:52.41 |
+05:36:18.8 |
HIP 116862 |
33.13 |
| 2026-08-03 12:00 |
23:42:49.30 |
+05:38:12.4 |
HIP 116862 |
33.95 |
| 2026-08-04 00:00 |
23:42:45.73 |
+05:40:03.1 |
HIP 116862 |
34.77 |
| 2026-08-04 12:00 |
23:42:41.71 |
+05:41:50.9 |
HIP 116862 |
35.59 |
| 2026-08-05 00:00 |
23:42:37.22 |
+05:43:35.8 |
HIP 116862 |
36.39 |
| 2026-08-05 12:00 |
23:42:32.28 |
+05:45:17.7 |
HIP 116862 |
37.20 |
| 2026-08-06 00:00 |
23:42:26.87 |
+05:46:56.6 |
HIP 116862 |
38.00 |
| 2026-08-06 12:00 |
23:42:21.00 |
+05:48:32.5 |
HIP 116771 |
37.49 |
| 2026-08-07 00:00 |
23:42:14.67 |
+05:50:05.3 |
HIP 116771 |
36.48 |
| 2026-08-07 12:00 |
23:42:07.87 |
+05:51:35.0 |
HIP 116877 |
35.07 |
| 2026-08-08 00:00 |
23:42:00.61 |
+05:53:01.6 |
HIP 116877 |
33.19 |
| 2026-08-08 12:00 |
23:41:52.89 |
+05:54:25.0 |
HIP 116877 |
31.40 |
| 2026-08-09 00:00 |
23:41:44.70 |
+05:55:45.3 |
HIP 116877 |
29.72 |
| 2026-08-09 12:00 |
23:41:36.04 |
+05:57:02.5 |
HIP 116877 |
28.20 |
| 2026-08-10 00:00 |
23:41:26.92 |
+05:58:16.4 |
HIP 116877 |
26.88 |
| 2026-08-10 12:00 |
23:41:17.34 |
+05:59:27.0 |
HIP 116877 |
25.82 |
| 2026-08-11 00:00 |
23:41:07.29 |
+06:00:34.4 |
HIP 116877 |
25.07 |
| 2026-08-11 12:00 |
23:40:56.78 |
+06:01:38.6 |
HIP 116877 |
24.69 |
| 2026-08-12 00:00 |
23:40:45.82 |
+06:02:39.4 |
HIP 116877 |
24.73 |
| 2026-08-12 12:00 |
23:40:34.39 |
+06:03:37.0 |
HIP 116715 |
22.54 |
| 2026-08-13 00:00 |
23:40:22.50 |
+06:04:31.2 |
HIP 116715 |
19.46 |
| 2026-08-13 12:00 |
23:40:10.15 |
+06:05:22.0 |
HIP 116715 |
16.31 |
| 2026-08-14 00:00 |
23:39:57.36 |
+06:06:09.5 |
HIP 116715 |
13.10 |
| 2026-08-14 12:00 |
23:39:44.11 |
+06:06:53.7 |
HIP 116715 |
9.86 |
| 2026-08-15 00:00 |
23:39:30.41 |
+06:07:34.4 |
HIP 116715 |
6.72 |
| 2026-08-15 12:00 |
23:39:16.26 |
+06:08:11.7 |
HIP 116715 |
4.15 |
| 2026-08-16 00:00 |
23:39:01.67 |
+06:08:45.7 |
HIP 116715 |
3.95 |
| 2026-08-16 12:00 |
23:38:46.63 |
+06:09:16.2 |
HIP 116715 |
6.53 |
| 2026-08-17 00:00 |
23:38:31.16 |
+06:09:43.3 |
HIP 116715 |
10.02 |
| 2026-08-17 12:00 |
23:38:15.26 |
+06:10:06.9 |
HIP 116715 |
13.83 |
| 2026-08-18 00:00 |
23:37:58.92 |
+06:10:27.2 |
HIP 116715 |
17.83 |
| 2026-08-18 12:00 |
23:37:42.15 |
+06:10:43.9 |
HIP 116521 |
20.62 |
| 2026-08-19 00:00 |
23:37:24.96 |
+06:10:57.2 |
HIP 116521 |
18.35 |