| Parameter |
Value |
| Designation |
C/2017 F2 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-11-26T04:31:31.609920Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:32Z |
| Obs used |
73 |
| NEO |
- |
| M1 |
7.000 |
| K1 |
11.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2017-09-02.0000000 |
| e |
1.00519546 |
| q (au) |
6.927697 |
| a (au) |
-1333.414094 |
| i (deg) |
42.507666 |
| Ω (om, deg) |
38.668006 |
| ω (w, deg) |
134.901946 |
| M (ma, deg) |
-0.001724 |
Magnitude
Scatter + Global Linear
$$
M_a = (3.109 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
3.109 |
| n |
6.000 |
| gf |
0.999 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
9.999 |
| 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 |
18:25:37.33 |
-59:09:33.6 |
HIP 90206 |
28.98 |
| 2026-03-26 12:00 |
18:25:39.83 |
-59:10:35.9 |
HIP 90206 |
28.11 |
| 2026-03-27 00:00 |
18:25:42.22 |
-59:11:38.3 |
HIP 90206 |
27.24 |
| 2026-03-27 12:00 |
18:25:44.52 |
-59:12:40.7 |
HIP 90206 |
26.39 |
| 2026-03-28 00:00 |
18:25:46.71 |
-59:13:43.2 |
HIP 90206 |
25.55 |
| 2026-03-28 12:00 |
18:25:48.79 |
-59:14:45.7 |
HIP 90206 |
24.72 |
| 2026-03-29 00:00 |
18:25:50.77 |
-59:15:48.3 |
HIP 90206 |
23.90 |
| 2026-03-29 12:00 |
18:25:52.65 |
-59:16:50.9 |
HIP 90206 |
23.10 |
| 2026-03-30 00:00 |
18:25:54.42 |
-59:17:53.6 |
HIP 90206 |
22.31 |
| 2026-03-30 12:00 |
18:25:56.09 |
-59:18:56.3 |
HIP 90206 |
21.53 |
| 2026-03-31 00:00 |
18:25:57.66 |
-59:19:59.0 |
HIP 90206 |
20.78 |
| 2026-03-31 12:00 |
18:25:59.12 |
-59:21:01.7 |
HIP 90206 |
20.04 |
| 2026-04-01 00:00 |
18:26:00.47 |
-59:22:04.5 |
HIP 90206 |
19.33 |
| 2026-04-01 12:00 |
18:26:01.72 |
-59:23:07.3 |
HIP 90206 |
18.64 |
| 2026-04-02 00:00 |
18:26:02.87 |
-59:24:10.0 |
HIP 90206 |
17.97 |
| 2026-04-02 12:00 |
18:26:03.91 |
-59:25:12.8 |
HIP 90206 |
17.34 |
| 2026-04-03 00:00 |
18:26:04.84 |
-59:26:15.7 |
HIP 90206 |
16.73 |
| 2026-04-03 12:00 |
18:26:05.67 |
-59:27:18.5 |
HIP 90206 |
16.17 |
| 2026-04-04 00:00 |
18:26:06.40 |
-59:28:21.3 |
HIP 90206 |
15.64 |
| 2026-04-04 12:00 |
18:26:07.02 |
-59:29:24.1 |
HIP 90206 |
15.15 |
| 2026-04-05 00:00 |
18:26:07.53 |
-59:30:26.9 |
HIP 90206 |
14.71 |
| 2026-04-05 12:00 |
18:26:07.94 |
-59:31:29.7 |
HIP 90206 |
14.32 |
| 2026-04-06 00:00 |
18:26:08.24 |
-59:32:32.4 |
HIP 90206 |
13.99 |
| 2026-04-06 12:00 |
18:26:08.43 |
-59:33:35.2 |
HIP 90206 |
13.72 |
| 2026-04-07 00:00 |
18:26:08.52 |
-59:34:37.9 |
HIP 90206 |
13.50 |
| 2026-04-07 12:00 |
18:26:08.51 |
-59:35:40.6 |
HIP 90206 |
13.36 |
| 2026-04-08 00:00 |
18:26:08.39 |
-59:36:43.2 |
HIP 90206 |
13.28 |
| 2026-04-08 12:00 |
18:26:08.16 |
-59:37:45.8 |
HIP 90206 |
13.27 |
| 2026-04-09 00:00 |
18:26:07.82 |
-59:38:48.4 |
HIP 90206 |
13.32 |
| 2026-04-09 12:00 |
18:26:07.38 |
-59:39:50.9 |
HIP 90206 |
13.45 |
| 2026-04-10 00:00 |
18:26:06.83 |
-59:40:53.4 |
HIP 90206 |
13.64 |
| 2026-04-10 12:00 |
18:26:06.18 |
-59:41:55.8 |
HIP 90206 |
13.90 |
| 2026-04-11 00:00 |
18:26:05.42 |
-59:42:58.2 |
HIP 90206 |
14.21 |
| 2026-04-11 12:00 |
18:26:04.55 |
-59:44:00.5 |
HIP 90206 |
14.58 |
| 2026-04-12 00:00 |
18:26:03.57 |
-59:45:02.7 |
HIP 90206 |
15.00 |
| 2026-04-12 12:00 |
18:26:02.49 |
-59:46:04.8 |
HIP 90206 |
15.47 |
| 2026-04-13 00:00 |
18:26:01.30 |
-59:47:06.9 |
HIP 90206 |
15.98 |
| 2026-04-13 12:00 |
18:26:00.01 |
-59:48:08.9 |
HIP 90206 |
16.53 |
| 2026-04-14 00:00 |
18:25:58.61 |
-59:49:10.8 |
HIP 90206 |
17.12 |
| 2026-04-14 12:00 |
18:25:57.10 |
-59:50:12.6 |
HIP 90309 |
16.44 |
| 2026-04-15 00:00 |
18:25:55.48 |
-59:51:14.3 |
HIP 90309 |
15.39 |
| 2026-04-15 12:00 |
18:25:53.76 |
-59:52:15.9 |
HIP 90309 |
14.34 |
| 2026-04-16 00:00 |
18:25:51.94 |
-59:53:17.4 |
HIP 90309 |
13.29 |