| Parameter |
Value |
| Designation |
380P/PANSTARRS |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2019-06-06T22:55:01.165440Z |
| Orbit solution date (soln_date, UTC) |
2023-02-06T22:13:34Z |
| Obs used |
266 |
| NEO |
- |
| M1 |
7.600 |
| K1 |
20.000 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2011-07-27T11:29:39.984000Z |
| Discovery magnitude (MPC) |
22.90 G |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2018-10-25.0000000 |
| e |
0.32644250 |
| q (au) |
3.049709 |
| a (au) |
4.527763 |
| i (deg) |
8.234018 |
| Ω (om, deg) |
133.114129 |
| ω (w, deg) |
90.060499 |
| M (ma, deg) |
336.986963 |
Magnitude
Scatter + Global Linear
$$
M_a = (9.310 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.310 |
| n |
6.000 |
| gf |
0.906 |
| gb |
-0.918 |
| k |
1.000 |
| δ90 |
5.286 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2018-01-16 |
2019-06-02 |
+10.1851 |
-5.046 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
06:01:19.60 |
+19:44:58.5 |
HIP 28495 |
7.05 |
| 2026-06-01 12:00 |
06:01:48.80 |
+19:45:19.4 |
HIP 28495 |
13.24 |
| 2026-06-02 00:00 |
06:02:18.05 |
+19:45:39.9 |
HIP 28691 |
16.85 |
| 2026-06-02 12:00 |
06:02:47.35 |
+19:46:00.0 |
HIP 28691 |
10.46 |
| 2026-06-03 00:00 |
06:03:16.69 |
+19:46:19.4 |
HIP 28691 |
5.49 |
| 2026-06-03 12:00 |
06:03:46.09 |
+19:46:38.5 |
HIP 28691 |
6.82 |
| 2026-06-04 00:00 |
06:04:15.52 |
+19:46:57.1 |
HIP 28691 |
12.60 |
| 2026-06-04 12:00 |
06:04:45.01 |
+19:47:15.3 |
HIP 28691 |
19.17 |
| 2026-06-05 00:00 |
06:05:14.54 |
+19:47:32.9 |
HIP 28691 |
25.95 |
| 2026-06-05 12:00 |
06:05:44.11 |
+19:47:50.1 |
HIP 28958 |
22.97 |
| 2026-06-06 00:00 |
06:06:13.73 |
+19:48:06.8 |
HIP 28958 |
19.39 |
| 2026-06-06 12:00 |
06:06:43.39 |
+19:48:23.1 |
HIP 28958 |
17.92 |
| 2026-06-07 00:00 |
06:07:13.09 |
+19:48:38.9 |
HIP 28958 |
19.09 |
| 2026-06-07 12:00 |
06:07:42.84 |
+19:48:54.2 |
HIP 28958 |
22.49 |
| 2026-06-08 00:00 |
06:08:12.63 |
+19:49:09.0 |
HIP 28958 |
27.31 |
| 2026-06-08 12:00 |
06:08:42.46 |
+19:49:23.3 |
HIP 28958 |
32.93 |
| 2026-06-09 00:00 |
06:09:12.32 |
+19:49:37.2 |
HIP 29190 |
35.89 |
| 2026-06-09 12:00 |
06:09:42.23 |
+19:49:50.6 |
HIP 29433 |
32.81 |
| 2026-06-10 00:00 |
06:10:12.18 |
+19:50:03.5 |
HIP 29433 |
25.81 |
| 2026-06-10 12:00 |
06:10:42.17 |
+19:50:15.9 |
HIP 29433 |
18.84 |
| 2026-06-11 00:00 |
06:11:12.19 |
+19:50:27.8 |
HIP 29433 |
11.95 |
| 2026-06-11 12:00 |
06:11:42.25 |
+19:50:39.3 |
HIP 29433 |
5.52 |
| 2026-06-12 00:00 |
06:12:12.35 |
+19:50:50.2 |
HIP 29433 |
4.28 |
| 2026-06-12 12:00 |
06:12:42.48 |
+19:51:00.7 |
HIP 29511 |
4.80 |
| 2026-06-13 00:00 |
06:13:12.65 |
+19:51:10.7 |
HIP 29511 |
3.48 |
| 2026-06-13 12:00 |
06:13:42.85 |
+19:51:20.2 |
HIP 29511 |
10.10 |
| 2026-06-14 00:00 |
06:14:13.08 |
+19:51:29.2 |
HIP 29511 |
17.12 |
| 2026-06-14 12:00 |
06:14:43.35 |
+19:51:37.8 |
HIP 29587 |
20.50 |
| 2026-06-15 00:00 |
06:15:13.65 |
+19:51:45.8 |
HIP 29786 |
21.61 |
| 2026-06-15 12:00 |
06:15:43.98 |
+19:51:53.3 |
HIP 29786 |
17.57 |
| 2026-06-16 00:00 |
06:16:14.34 |
+19:52:00.4 |
HIP 29786 |
15.86 |
| 2026-06-16 12:00 |
06:16:44.73 |
+19:52:07.0 |
HIP 29786 |
17.22 |
| 2026-06-17 00:00 |
06:17:15.14 |
+19:52:13.1 |
HIP 29786 |
21.07 |
| 2026-06-17 12:00 |
06:17:45.59 |
+19:52:18.6 |
HIP 29909 |
24.91 |
| 2026-06-18 00:00 |
06:18:16.06 |
+19:52:23.7 |
HIP 29909 |
25.66 |
| 2026-06-18 12:00 |
06:18:46.56 |
+19:52:28.3 |
HIP 30110 |
20.12 |
| 2026-06-19 00:00 |
06:19:17.08 |
+19:52:32.5 |
HIP 30110 |
12.94 |
| 2026-06-19 12:00 |
06:19:47.63 |
+19:52:36.1 |
HIP 30110 |
5.76 |
| 2026-06-20 00:00 |
06:20:18.20 |
+19:52:39.2 |
HIP 30110 |
1.44 |
| 2026-06-20 12:00 |
06:20:48.79 |
+19:52:41.9 |
HIP 30110 |
8.63 |
| 2026-06-21 00:00 |
06:21:19.41 |
+19:52:44.0 |
HIP 30229 |
3.90 |
| 2026-06-21 12:00 |
06:21:50.05 |
+19:52:45.7 |
HIP 30229 |
3.46 |
| 2026-06-22 00:00 |
06:22:20.71 |
+19:52:46.9 |
HIP 30229 |
10.61 |