| Parameter |
Value |
| Designation |
P/2017 P1 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2018-06-18T14:00:59.025600Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:35Z |
| Obs used |
46 |
| NEO |
- |
| M1 |
14.200 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2017-08-29.0000000 |
| e |
0.30846643 |
| q (au) |
5.438117 |
| a (au) |
7.863851 |
| i (deg) |
7.701554 |
| Ω (om, deg) |
221.393844 |
| ω (w, deg) |
122.270978 |
| M (ma, deg) |
346.878497 |
Magnitude
Scatter + Global Linear
$$
M_a = (16.305 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
16.305 |
| n |
2.000 |
| gf |
0.977 |
| gb |
-0.687 |
| k |
0.800 |
| δ90 |
9.531 |
| 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 |
09:24:48.17 |
+07:45:26.4 |
HIP 46053 |
19.65 |
| 2026-09-20 12:00 |
09:24:59.23 |
+07:44:20.4 |
HIP 46053 |
22.27 |
| 2026-09-21 00:00 |
09:25:10.24 |
+07:43:14.5 |
HIP 46303 |
20.97 |
| 2026-09-21 12:00 |
09:25:21.21 |
+07:42:08.7 |
HIP 46303 |
18.16 |
| 2026-09-22 00:00 |
09:25:32.12 |
+07:41:03.0 |
HIP 46303 |
15.40 |
| 2026-09-22 12:00 |
09:25:42.99 |
+07:39:57.3 |
HIP 46303 |
12.73 |
| 2026-09-23 00:00 |
09:25:53.81 |
+07:38:51.6 |
HIP 46303 |
10.20 |
| 2026-09-23 12:00 |
09:26:04.57 |
+07:37:46.1 |
HIP 46303 |
7.92 |
| 2026-09-24 00:00 |
09:26:15.29 |
+07:36:40.6 |
HIP 46303 |
6.19 |
| 2026-09-24 12:00 |
09:26:25.95 |
+07:35:35.2 |
HIP 46303 |
5.52 |
| 2026-09-25 00:00 |
09:26:36.56 |
+07:34:29.8 |
HIP 46303 |
6.23 |
| 2026-09-25 12:00 |
09:26:47.13 |
+07:33:24.6 |
HIP 46303 |
7.96 |
| 2026-09-26 00:00 |
09:26:57.63 |
+07:32:19.4 |
HIP 46303 |
10.18 |
| 2026-09-26 12:00 |
09:27:08.09 |
+07:31:14.3 |
HIP 46303 |
12.64 |
| 2026-09-27 00:00 |
09:27:18.49 |
+07:30:09.3 |
HIP 46400 |
10.16 |
| 2026-09-27 12:00 |
09:27:28.84 |
+07:29:04.4 |
HIP 46400 |
7.87 |
| 2026-09-28 00:00 |
09:27:39.13 |
+07:27:59.6 |
HIP 46400 |
6.01 |
| 2026-09-28 12:00 |
09:27:49.37 |
+07:26:55.0 |
HIP 46400 |
5.07 |
| 2026-09-29 00:00 |
09:27:59.55 |
+07:25:50.4 |
HIP 46400 |
5.51 |
| 2026-09-29 12:00 |
09:28:09.68 |
+07:24:45.9 |
HIP 46400 |
7.06 |
| 2026-09-30 00:00 |
09:28:19.75 |
+07:23:41.5 |
HIP 46400 |
9.17 |
| 2026-09-30 12:00 |
09:28:29.77 |
+07:22:37.2 |
HIP 46400 |
11.52 |
| 2026-10-01 00:00 |
09:28:39.73 |
+07:21:33.1 |
HIP 46400 |
13.99 |
| 2026-10-01 12:00 |
09:28:49.63 |
+07:20:29.1 |
HIP 46400 |
16.51 |
| 2026-10-02 00:00 |
09:28:59.47 |
+07:19:25.2 |
HIP 46400 |
19.06 |
| 2026-10-02 12:00 |
09:29:09.25 |
+07:18:21.4 |
HIP 46447 |
21.21 |
| 2026-10-03 00:00 |
09:29:18.97 |
+07:17:17.8 |
HIP 46447 |
21.75 |
| 2026-10-03 12:00 |
09:29:28.64 |
+07:16:14.3 |
HIP 46447 |
22.59 |
| 2026-10-04 00:00 |
09:29:38.24 |
+07:15:10.9 |
HIP 46447 |
23.67 |
| 2026-10-04 12:00 |
09:29:47.78 |
+07:14:07.7 |
HIP 46447 |
24.97 |
| 2026-10-05 00:00 |
09:29:57.26 |
+07:13:04.6 |
HIP 46447 |
26.45 |
| 2026-10-05 12:00 |
09:30:06.68 |
+07:12:01.6 |
HIP 46761 |
26.59 |
| 2026-10-06 00:00 |
09:30:16.04 |
+07:10:58.9 |
HIP 46761 |
24.59 |
| 2026-10-06 12:00 |
09:30:25.33 |
+07:09:56.2 |
HIP 46761 |
22.72 |
| 2026-10-07 00:00 |
09:30:34.56 |
+07:08:53.8 |
HIP 46761 |
20.99 |
| 2026-10-07 12:00 |
09:30:43.73 |
+07:07:51.5 |
HIP 46761 |
19.46 |
| 2026-10-08 00:00 |
09:30:52.83 |
+07:06:49.3 |
HIP 46761 |
18.15 |
| 2026-10-08 12:00 |
09:31:01.86 |
+07:05:47.4 |
HIP 46761 |
17.11 |
| 2026-10-09 00:00 |
09:31:10.83 |
+07:04:45.6 |
HIP 46761 |
16.39 |
| 2026-10-09 12:00 |
09:31:19.74 |
+07:03:44.0 |
HIP 46761 |
16.02 |
| 2026-10-10 00:00 |
09:31:28.57 |
+07:02:42.6 |
HIP 46826 |
15.86 |
| 2026-10-10 12:00 |
09:31:37.34 |
+07:01:41.3 |
HIP 46826 |
13.81 |
| 2026-10-11 00:00 |
09:31:46.04 |
+07:00:40.3 |
HIP 46826 |
11.91 |