| 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) |
| 2026-03-26 00:00 |
08:32:09.56 |
+10:25:29.6 |
HIP 41904 |
22.79 |
| 2026-03-26 12:00 |
08:32:06.47 |
+10:26:04.6 |
HIP 41904 |
23.59 |
| 2026-03-27 00:00 |
08:32:03.47 |
+10:26:39.3 |
HIP 41904 |
24.40 |
| 2026-03-27 12:00 |
08:32:00.58 |
+10:27:13.8 |
HIP 41904 |
25.20 |
| 2026-03-28 00:00 |
08:31:57.79 |
+10:27:47.9 |
HIP 41904 |
25.99 |
| 2026-03-28 12:00 |
08:31:55.09 |
+10:28:21.7 |
HIP 41904 |
26.77 |
| 2026-03-29 00:00 |
08:31:52.50 |
+10:28:55.3 |
HIP 41904 |
27.55 |
| 2026-03-29 12:00 |
08:31:50.01 |
+10:29:28.5 |
HIP 41904 |
28.31 |
| 2026-03-30 00:00 |
08:31:47.62 |
+10:30:01.4 |
HIP 41904 |
29.06 |
| 2026-03-30 12:00 |
08:31:45.33 |
+10:30:34.1 |
HIP 41904 |
29.80 |
| 2026-03-31 00:00 |
08:31:43.14 |
+10:31:06.4 |
HIP 41904 |
30.52 |
| 2026-03-31 12:00 |
08:31:41.05 |
+10:31:38.4 |
HIP 41904 |
31.23 |
| 2026-04-01 00:00 |
08:31:39.07 |
+10:32:10.1 |
HIP 41904 |
31.93 |
| 2026-04-01 12:00 |
08:31:37.18 |
+10:32:41.4 |
HIP 41904 |
32.60 |
| 2026-04-02 00:00 |
08:31:35.40 |
+10:33:12.5 |
HIP 41904 |
33.27 |
| 2026-04-02 12:00 |
08:31:33.72 |
+10:33:43.2 |
HIP 41904 |
33.92 |
| 2026-04-03 00:00 |
08:31:32.14 |
+10:34:13.6 |
HIP 41904 |
34.55 |
| 2026-04-03 12:00 |
08:31:30.66 |
+10:34:43.7 |
HIP 41904 |
35.16 |
| 2026-04-04 00:00 |
08:31:29.29 |
+10:35:13.5 |
HIP 41904 |
35.76 |
| 2026-04-04 12:00 |
08:31:28.02 |
+10:35:42.9 |
HIP 41904 |
36.34 |
| 2026-04-05 00:00 |
08:31:26.84 |
+10:36:12.0 |
HIP 41904 |
36.90 |
| 2026-04-05 12:00 |
08:31:25.77 |
+10:36:40.8 |
HIP 41904 |
37.45 |
| 2026-04-06 00:00 |
08:31:24.81 |
+10:37:09.2 |
HIP 42023 |
37.72 |
| 2026-04-06 12:00 |
08:31:23.94 |
+10:37:37.3 |
HIP 42023 |
37.96 |
| 2026-04-07 00:00 |
08:31:23.18 |
+10:38:05.0 |
HIP 42023 |
38.17 |
| 2026-04-07 12:00 |
08:31:22.52 |
+10:38:32.4 |
HIP 42023 |
38.37 |
| 2026-04-08 00:00 |
08:31:21.96 |
+10:38:59.5 |
HIP 42023 |
38.55 |
| 2026-04-08 12:00 |
08:31:21.51 |
+10:39:26.2 |
HIP 42023 |
38.71 |
| 2026-04-09 00:00 |
08:31:21.15 |
+10:39:52.5 |
HIP 42023 |
38.85 |
| 2026-04-09 12:00 |
08:31:20.90 |
+10:40:18.5 |
HIP 42023 |
38.96 |
| 2026-04-10 00:00 |
08:31:20.75 |
+10:40:44.2 |
HIP 42023 |
39.06 |
| 2026-04-10 12:00 |
08:31:20.71 |
+10:41:09.5 |
HIP 42023 |
39.13 |
| 2026-04-11 00:00 |
08:31:20.77 |
+10:41:34.4 |
HIP 42023 |
39.18 |
| 2026-04-11 12:00 |
08:31:20.93 |
+10:41:59.0 |
HIP 42023 |
39.21 |
| 2026-04-12 00:00 |
08:31:21.19 |
+10:42:23.2 |
HIP 42023 |
39.22 |
| 2026-04-12 12:00 |
08:31:21.55 |
+10:42:47.1 |
HIP 42023 |
39.20 |
| 2026-04-13 00:00 |
08:31:22.02 |
+10:43:10.5 |
HIP 42023 |
39.17 |
| 2026-04-13 12:00 |
08:31:22.59 |
+10:43:33.7 |
HIP 42023 |
39.11 |
| 2026-04-14 00:00 |
08:31:23.26 |
+10:43:56.4 |
HIP 42023 |
39.04 |
| 2026-04-14 12:00 |
08:31:24.03 |
+10:44:18.8 |
HIP 42023 |
38.94 |
| 2026-04-15 00:00 |
08:31:24.91 |
+10:44:40.8 |
HIP 42023 |
38.81 |
| 2026-04-15 12:00 |
08:31:25.89 |
+10:45:02.4 |
HIP 42023 |
38.67 |
| 2026-04-16 00:00 |
08:31:26.97 |
+10:45:23.6 |
HIP 42023 |
38.51 |