| 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
$$
M_a = (16.307 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
16.307 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.687 |
| k |
0.800 |
| δ90 |
9.708 |
| 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) |
| 2026-05-12 00:00 |
08:34:37.48 |
+10:54:38.1 |
HIP 42023 |
21.73 |
| 2026-05-12 12:00 |
08:34:43.57 |
+10:54:37.9 |
HIP 42023 |
22.44 |
| 2026-05-13 00:00 |
08:34:49.74 |
+10:54:37.2 |
HIP 42112 |
22.69 |
| 2026-05-13 12:00 |
08:34:56.00 |
+10:54:36.2 |
HIP 42112 |
22.52 |
| 2026-05-14 00:00 |
08:35:02.35 |
+10:54:34.8 |
HIP 42112 |
22.46 |
| 2026-05-14 12:00 |
08:35:08.78 |
+10:54:32.9 |
HIP 42112 |
22.51 |
| 2026-05-15 00:00 |
08:35:15.29 |
+10:54:30.6 |
HIP 42112 |
22.68 |
| 2026-05-15 12:00 |
08:35:21.88 |
+10:54:27.9 |
HIP 42112 |
22.98 |
| 2026-05-16 00:00 |
08:35:28.56 |
+10:54:24.8 |
HIP 42112 |
23.39 |
| 2026-05-16 12:00 |
08:35:35.32 |
+10:54:21.2 |
HIP 42112 |
23.93 |
| 2026-05-17 00:00 |
08:35:42.17 |
+10:54:17.3 |
HIP 42112 |
24.57 |
| 2026-05-17 12:00 |
08:35:49.09 |
+10:54:12.9 |
HIP 42112 |
25.33 |
| 2026-05-18 00:00 |
08:35:56.10 |
+10:54:08.1 |
HIP 42112 |
26.19 |
| 2026-05-18 12:00 |
08:36:03.18 |
+10:54:02.8 |
HIP 42112 |
27.16 |
| 2026-05-19 00:00 |
08:36:10.35 |
+10:53:57.2 |
HIP 42112 |
28.21 |
| 2026-05-19 12:00 |
08:36:17.59 |
+10:53:51.1 |
HIP 42355 |
27.16 |
| 2026-05-20 00:00 |
08:36:24.91 |
+10:53:44.7 |
HIP 42355 |
25.36 |
| 2026-05-20 12:00 |
08:36:32.32 |
+10:53:37.8 |
HIP 42355 |
23.54 |
| 2026-05-21 00:00 |
08:36:39.80 |
+10:53:30.4 |
HIP 42355 |
21.70 |
| 2026-05-21 12:00 |
08:36:47.35 |
+10:53:22.7 |
HIP 42355 |
19.84 |
| 2026-05-22 00:00 |
08:36:54.98 |
+10:53:14.6 |
HIP 42355 |
17.96 |
| 2026-05-22 12:00 |
08:37:02.69 |
+10:53:06.0 |
HIP 42355 |
16.07 |
| 2026-05-23 00:00 |
08:37:10.48 |
+10:52:57.0 |
HIP 42355 |
14.15 |
| 2026-05-23 12:00 |
08:37:18.34 |
+10:52:47.6 |
HIP 42355 |
12.21 |
| 2026-05-24 00:00 |
08:37:26.27 |
+10:52:37.8 |
HIP 42355 |
10.26 |
| 2026-05-24 12:00 |
08:37:34.28 |
+10:52:27.6 |
HIP 42355 |
8.29 |
| 2026-05-25 00:00 |
08:37:42.36 |
+10:52:17.0 |
HIP 42355 |
6.30 |
| 2026-05-25 12:00 |
08:37:50.51 |
+10:52:06.0 |
HIP 42355 |
4.29 |
| 2026-05-26 00:00 |
08:37:58.74 |
+10:51:54.5 |
HIP 42355 |
2.27 |
| 2026-05-26 12:00 |
08:38:07.04 |
+10:51:42.7 |
HIP 42355 |
0.36 |
| 2026-05-27 00:00 |
08:38:15.41 |
+10:51:30.4 |
HIP 42355 |
1.89 |
| 2026-05-27 12:00 |
08:38:23.85 |
+10:51:17.7 |
HIP 42355 |
3.96 |
| 2026-05-28 00:00 |
08:38:32.36 |
+10:51:04.7 |
HIP 42355 |
6.05 |
| 2026-05-28 12:00 |
08:38:40.94 |
+10:50:51.2 |
HIP 42355 |
8.17 |
| 2026-05-29 00:00 |
08:38:49.59 |
+10:50:37.3 |
HIP 42355 |
10.31 |
| 2026-05-29 12:00 |
08:38:58.30 |
+10:50:23.0 |
HIP 42355 |
12.46 |
| 2026-05-30 00:00 |
08:39:07.09 |
+10:50:08.3 |
HIP 42355 |
14.63 |
| 2026-05-30 12:00 |
08:39:15.94 |
+10:49:53.2 |
HIP 42355 |
16.82 |
| 2026-05-31 00:00 |
08:39:24.87 |
+10:49:37.7 |
HIP 42560 |
17.61 |
| 2026-05-31 12:00 |
08:39:33.85 |
+10:49:21.8 |
HIP 42560 |
15.64 |
| 2026-06-01 00:00 |
08:39:42.91 |
+10:49:05.5 |
HIP 42560 |
13.75 |
| 2026-06-01 12:00 |
08:39:52.03 |
+10:48:48.8 |
HIP 42560 |
11.96 |
| 2026-06-02 00:00 |
08:40:01.21 |
+10:48:31.7 |
HIP 42560 |
10.35 |