| Parameter |
Value |
| Designation |
C/2017 D5 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-01-08T20:46:08.676480Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:31Z |
| Obs used |
75 |
| NEO |
- |
| M1 |
14.700 |
| K1 |
13.750 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2017-03-05.0000000 |
| e |
0.98076543 |
| q (au) |
2.167199 |
| a (au) |
112.672079 |
| i (deg) |
131.038508 |
| Ω (om, deg) |
92.721040 |
| ω (w, deg) |
287.822322 |
| M (ma, deg) |
0.045436 |
Magnitude
Scatter + Global Linear
$$
M_a = (13.560 + 5.726\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.560 |
| n |
5.726 |
| gf |
1.000 |
| gb |
-0.978 |
| k |
1.000 |
| δ90 |
10.000 |
| 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 |
23:59:01.26 |
+54:01:10.1 |
HIP 61 |
19.01 |
| 2026-09-20 12:00 |
23:58:52.28 |
+54:00:51.0 |
HIP 61 |
19.87 |
| 2026-09-21 00:00 |
23:58:43.29 |
+54:00:31.2 |
HIP 118036 |
19.28 |
| 2026-09-21 12:00 |
23:58:34.30 |
+54:00:10.8 |
HIP 118036 |
17.93 |
| 2026-09-22 00:00 |
23:58:25.32 |
+53:59:49.9 |
HIP 118036 |
16.57 |
| 2026-09-22 12:00 |
23:58:16.33 |
+53:59:28.4 |
HIP 118036 |
15.22 |
| 2026-09-23 00:00 |
23:58:07.35 |
+53:59:06.2 |
HIP 118036 |
13.86 |
| 2026-09-23 12:00 |
23:57:58.37 |
+53:58:43.5 |
HIP 118036 |
12.51 |
| 2026-09-24 00:00 |
23:57:49.39 |
+53:58:20.2 |
HIP 118036 |
11.17 |
| 2026-09-24 12:00 |
23:57:40.42 |
+53:57:56.3 |
HIP 118036 |
9.83 |
| 2026-09-25 00:00 |
23:57:31.46 |
+53:57:31.8 |
HIP 118036 |
8.51 |
| 2026-09-25 12:00 |
23:57:22.49 |
+53:57:06.8 |
HIP 118036 |
7.21 |
| 2026-09-26 00:00 |
23:57:13.54 |
+53:56:41.1 |
HIP 118036 |
5.95 |
| 2026-09-26 12:00 |
23:57:04.59 |
+53:56:14.9 |
HIP 118036 |
4.76 |
| 2026-09-27 00:00 |
23:56:55.65 |
+53:55:48.1 |
HIP 118036 |
3.71 |
| 2026-09-27 12:00 |
23:56:46.72 |
+53:55:20.8 |
HIP 118036 |
2.97 |
| 2026-09-28 00:00 |
23:56:37.80 |
+53:54:52.8 |
HIP 118036 |
2.80 |
| 2026-09-28 12:00 |
23:56:28.89 |
+53:54:24.3 |
HIP 118036 |
3.28 |
| 2026-09-29 00:00 |
23:56:19.98 |
+53:53:55.2 |
HIP 118036 |
4.20 |
| 2026-09-29 12:00 |
23:56:11.09 |
+53:53:25.6 |
HIP 118036 |
5.34 |
| 2026-09-30 00:00 |
23:56:02.22 |
+53:52:55.4 |
HIP 118036 |
6.58 |
| 2026-09-30 12:00 |
23:55:53.35 |
+53:52:24.6 |
HIP 118036 |
7.89 |
| 2026-10-01 00:00 |
23:55:44.50 |
+53:51:53.2 |
HIP 118036 |
9.22 |
| 2026-10-01 12:00 |
23:55:35.66 |
+53:51:21.3 |
HIP 118036 |
10.58 |
| 2026-10-02 00:00 |
23:55:26.84 |
+53:50:48.9 |
HIP 118036 |
11.96 |
| 2026-10-02 12:00 |
23:55:18.03 |
+53:50:15.8 |
HIP 118032 |
13.15 |
| 2026-10-03 00:00 |
23:55:09.24 |
+53:49:42.3 |
HIP 118032 |
13.95 |
| 2026-10-03 12:00 |
23:55:00.47 |
+53:49:08.1 |
HIP 118032 |
14.83 |
| 2026-10-04 00:00 |
23:54:51.71 |
+53:48:33.4 |
HIP 118032 |
15.79 |
| 2026-10-04 12:00 |
23:54:42.97 |
+53:47:58.2 |
HIP 118032 |
16.81 |
| 2026-10-05 00:00 |
23:54:34.26 |
+53:47:22.4 |
HIP 117892 |
17.67 |
| 2026-10-05 12:00 |
23:54:25.56 |
+53:46:46.1 |
HIP 117892 |
17.29 |
| 2026-10-06 00:00 |
23:54:16.88 |
+53:46:09.2 |
HIP 117892 |
17.00 |
| 2026-10-06 12:00 |
23:54:08.23 |
+53:45:31.8 |
HIP 117892 |
16.82 |
| 2026-10-07 00:00 |
23:53:59.59 |
+53:44:53.9 |
HIP 117892 |
16.76 |
| 2026-10-07 12:00 |
23:53:50.98 |
+53:44:15.4 |
HIP 117892 |
16.80 |
| 2026-10-08 00:00 |
23:53:42.40 |
+53:43:36.4 |
HIP 117892 |
16.96 |
| 2026-10-08 12:00 |
23:53:33.84 |
+53:42:56.9 |
HIP 117741 |
16.33 |
| 2026-10-09 00:00 |
23:53:25.30 |
+53:42:16.8 |
HIP 117741 |
15.18 |
| 2026-10-09 12:00 |
23:53:16.79 |
+53:41:36.3 |
HIP 117741 |
14.08 |
| 2026-10-10 00:00 |
23:53:08.31 |
+53:40:55.2 |
HIP 117741 |
13.04 |
| 2026-10-10 12:00 |
23:52:59.86 |
+53:40:13.6 |
HIP 117741 |
12.07 |
| 2026-10-11 00:00 |
23:52:51.43 |
+53:39:31.5 |
HIP 117741 |
11.19 |