| Parameter |
Value |
| Designation |
C/2015 D3 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2016-05-01T09:15:21.309120Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:07Z |
| Obs used |
313 |
| NEO |
- |
| M1 |
10.900 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2016-09-03.0000000 |
| e |
1.00219956 |
| q (au) |
8.148902 |
| a (au) |
-3704.795712 |
| i (deg) |
128.506522 |
| Ω (om, deg) |
156.980044 |
| ω (w, deg) |
2.885623 |
| M (ma, deg) |
0.000545 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.026 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.026 |
| n |
2.000 |
| gf |
0.907 |
| gb |
-0.987 |
| k |
1.000 |
| δ90 |
1.000 |
| 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 |
00:51:30.85 |
+61:33:22.7 |
HIP 3988 |
15.05 |
| 2026-09-20 12:00 |
00:51:19.16 |
+61:33:10.9 |
HIP 3988 |
15.15 |
| 2026-09-21 00:00 |
00:51:07.45 |
+61:32:58.4 |
HIP 3988 |
15.39 |
| 2026-09-21 12:00 |
00:50:55.72 |
+61:32:45.3 |
HIP 3988 |
15.77 |
| 2026-09-22 00:00 |
00:50:43.96 |
+61:32:31.4 |
HIP 3988 |
16.27 |
| 2026-09-22 12:00 |
00:50:32.18 |
+61:32:16.9 |
HIP 3767 |
15.69 |
| 2026-09-23 00:00 |
00:50:20.38 |
+61:32:01.6 |
HIP 3767 |
14.36 |
| 2026-09-23 12:00 |
00:50:08.56 |
+61:31:45.8 |
HIP 3767 |
13.05 |
| 2026-09-24 00:00 |
00:49:56.71 |
+61:31:29.2 |
HIP 3767 |
11.78 |
| 2026-09-24 12:00 |
00:49:44.85 |
+61:31:11.9 |
HIP 3767 |
10.54 |
| 2026-09-25 00:00 |
00:49:32.97 |
+61:30:54.0 |
HIP 3767 |
9.37 |
| 2026-09-25 12:00 |
00:49:21.08 |
+61:30:35.4 |
HIP 3767 |
8.29 |
| 2026-09-26 00:00 |
00:49:09.16 |
+61:30:16.1 |
HIP 3767 |
7.34 |
| 2026-09-26 12:00 |
00:48:57.24 |
+61:29:56.1 |
HIP 3767 |
6.59 |
| 2026-09-27 00:00 |
00:48:45.30 |
+61:29:35.4 |
HIP 3767 |
6.12 |
| 2026-09-27 12:00 |
00:48:33.34 |
+61:29:14.1 |
HIP 3767 |
5.98 |
| 2026-09-28 00:00 |
00:48:21.38 |
+61:28:52.0 |
HIP 3767 |
6.21 |
| 2026-09-28 12:00 |
00:48:09.40 |
+61:28:29.3 |
HIP 3767 |
6.77 |
| 2026-09-29 00:00 |
00:47:57.42 |
+61:28:05.9 |
HIP 3767 |
7.59 |
| 2026-09-29 12:00 |
00:47:45.42 |
+61:27:41.9 |
HIP 3767 |
8.60 |
| 2026-09-30 00:00 |
00:47:33.42 |
+61:27:17.1 |
HIP 3767 |
9.74 |
| 2026-09-30 12:00 |
00:47:21.41 |
+61:26:51.7 |
HIP 3767 |
10.98 |
| 2026-10-01 00:00 |
00:47:09.40 |
+61:26:25.6 |
HIP 3767 |
12.28 |
| 2026-10-01 12:00 |
00:46:57.38 |
+61:25:58.8 |
HIP 3767 |
13.63 |
| 2026-10-02 00:00 |
00:46:45.36 |
+61:25:31.3 |
HIP 3767 |
15.02 |
| 2026-10-02 12:00 |
00:46:33.33 |
+61:25:03.1 |
HIP 3767 |
16.43 |
| 2026-10-03 00:00 |
00:46:21.31 |
+61:24:34.3 |
HIP 3767 |
17.87 |
| 2026-10-03 12:00 |
00:46:09.28 |
+61:24:04.8 |
HIP 3767 |
19.33 |
| 2026-10-04 00:00 |
00:45:57.25 |
+61:23:34.6 |
HIP 3767 |
20.80 |
| 2026-10-04 12:00 |
00:45:45.23 |
+61:23:03.7 |
HIP 3767 |
22.29 |
| 2026-10-05 00:00 |
00:45:33.20 |
+61:22:32.1 |
HIP 3767 |
23.78 |
| 2026-10-05 12:00 |
00:45:21.19 |
+61:22:00.0 |
HIP 3442 |
23.29 |
| 2026-10-06 00:00 |
00:45:09.17 |
+61:21:27.0 |
HIP 3442 |
22.20 |
| 2026-10-06 12:00 |
00:44:57.16 |
+61:20:53.4 |
HIP 3442 |
21.16 |
| 2026-10-07 00:00 |
00:44:45.16 |
+61:20:19.2 |
HIP 3442 |
20.18 |
| 2026-10-07 12:00 |
00:44:33.17 |
+61:19:44.2 |
HIP 3442 |
19.26 |
| 2026-10-08 00:00 |
00:44:21.19 |
+61:19:08.6 |
HIP 3442 |
18.41 |
| 2026-10-08 12:00 |
00:44:09.22 |
+61:18:32.4 |
HIP 3442 |
17.65 |
| 2026-10-09 00:00 |
00:43:57.26 |
+61:17:55.4 |
HIP 3442 |
16.99 |
| 2026-10-09 12:00 |
00:43:45.31 |
+61:17:17.8 |
HIP 3442 |
16.44 |
| 2026-10-10 00:00 |
00:43:33.37 |
+61:16:39.6 |
HIP 3442 |
16.02 |
| 2026-10-10 12:00 |
00:43:21.46 |
+61:16:00.6 |
HIP 3442 |
15.74 |
| 2026-10-11 00:00 |
00:43:09.55 |
+61:15:21.0 |
HIP 3442 |
15.59 |