| 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 |
0.906 |
| 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) |
| 2026-05-12 00:00 |
01:02:25.46 |
+58:47:52.6 |
HIP 4961 |
11.41 |
| 2026-05-12 12:00 |
01:02:32.20 |
+58:48:31.8 |
HIP 4961 |
10.32 |
| 2026-05-13 00:00 |
01:02:38.89 |
+58:49:11.3 |
HIP 4961 |
9.23 |
| 2026-05-13 12:00 |
01:02:45.55 |
+58:49:51.2 |
HIP 4961 |
8.15 |
| 2026-05-14 00:00 |
01:02:52.15 |
+58:50:31.4 |
HIP 4961 |
7.06 |
| 2026-05-14 12:00 |
01:02:58.72 |
+58:51:11.9 |
HIP 4961 |
5.98 |
| 2026-05-15 00:00 |
01:03:05.23 |
+58:51:52.7 |
HIP 4961 |
4.90 |
| 2026-05-15 12:00 |
01:03:11.71 |
+58:52:33.9 |
HIP 4961 |
3.83 |
| 2026-05-16 00:00 |
01:03:18.13 |
+58:53:15.3 |
HIP 4961 |
2.76 |
| 2026-05-16 12:00 |
01:03:24.51 |
+58:53:57.1 |
HIP 4961 |
1.72 |
| 2026-05-17 00:00 |
01:03:30.84 |
+58:54:39.2 |
HIP 4961 |
0.80 |
| 2026-05-17 12:00 |
01:03:37.13 |
+58:55:21.6 |
HIP 4961 |
0.80 |
| 2026-05-18 00:00 |
01:03:43.37 |
+58:56:04.3 |
HIP 4961 |
1.72 |
| 2026-05-18 12:00 |
01:03:49.55 |
+58:56:47.3 |
HIP 4961 |
2.76 |
| 2026-05-19 00:00 |
01:03:55.69 |
+58:57:30.5 |
HIP 4961 |
3.81 |
| 2026-05-19 12:00 |
01:04:01.78 |
+58:58:14.1 |
HIP 4961 |
4.87 |
| 2026-05-20 00:00 |
01:04:07.82 |
+58:58:57.9 |
HIP 4961 |
5.94 |
| 2026-05-20 12:00 |
01:04:13.81 |
+58:59:42.1 |
HIP 4961 |
7.00 |
| 2026-05-21 00:00 |
01:04:19.75 |
+59:00:26.5 |
HIP 4961 |
8.06 |
| 2026-05-21 12:00 |
01:04:25.63 |
+59:01:11.1 |
HIP 4961 |
9.12 |
| 2026-05-22 00:00 |
01:04:31.46 |
+59:01:56.1 |
HIP 4961 |
10.18 |
| 2026-05-22 12:00 |
01:04:37.24 |
+59:02:41.3 |
HIP 4961 |
11.24 |
| 2026-05-23 00:00 |
01:04:42.97 |
+59:03:26.8 |
HIP 4961 |
12.30 |
| 2026-05-23 12:00 |
01:04:48.65 |
+59:04:12.5 |
HIP 4961 |
13.35 |
| 2026-05-24 00:00 |
01:04:54.27 |
+59:04:58.5 |
HIP 4961 |
14.41 |
| 2026-05-24 12:00 |
01:04:59.83 |
+59:05:44.7 |
HIP 4961 |
15.46 |
| 2026-05-25 00:00 |
01:05:05.34 |
+59:06:31.2 |
HIP 4961 |
16.51 |
| 2026-05-25 12:00 |
01:05:10.80 |
+59:07:17.9 |
HIP 4961 |
17.55 |
| 2026-05-26 00:00 |
01:05:16.20 |
+59:08:04.9 |
HIP 4961 |
18.60 |
| 2026-05-26 12:00 |
01:05:21.54 |
+59:08:52.1 |
HIP 4961 |
19.64 |
| 2026-05-27 00:00 |
01:05:26.83 |
+59:09:39.6 |
HIP 4961 |
20.68 |
| 2026-05-27 12:00 |
01:05:32.06 |
+59:10:27.2 |
HIP 4961 |
21.72 |
| 2026-05-28 00:00 |
01:05:37.24 |
+59:11:15.1 |
HIP 4961 |
22.75 |
| 2026-05-28 12:00 |
01:05:42.35 |
+59:12:03.2 |
HIP 4961 |
23.79 |
| 2026-05-29 00:00 |
01:05:47.41 |
+59:12:51.6 |
HIP 4871 |
24.70 |
| 2026-05-29 12:00 |
01:05:52.41 |
+59:13:40.1 |
HIP 4871 |
25.20 |
| 2026-05-30 00:00 |
01:05:57.35 |
+59:14:28.9 |
HIP 4871 |
25.72 |
| 2026-05-30 12:00 |
01:06:02.24 |
+59:15:17.9 |
HIP 4871 |
26.27 |
| 2026-05-31 00:00 |
01:06:07.06 |
+59:16:07.1 |
HIP 4871 |
26.83 |
| 2026-05-31 12:00 |
01:06:11.82 |
+59:16:56.5 |
HIP 4871 |
27.41 |
| 2026-06-01 00:00 |
01:06:16.52 |
+59:17:46.1 |
HIP 4871 |
28.01 |
| 2026-06-01 12:00 |
01:06:21.16 |
+59:18:35.8 |
HIP 4871 |
28.63 |
| 2026-06-02 00:00 |
01:06:25.74 |
+59:19:25.8 |
HIP 4871 |
29.26 |