| Parameter |
Value |
| Designation |
P/2015 Q2 (Pimentel) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2015-09-10T08:08:29.523840Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:13Z |
| Obs used |
60 |
| NEO |
- |
| M1 |
15.300 |
| K1 |
10.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2015-09-11.0000000 |
| e |
0.75436589 |
| q (au) |
1.819120 |
| a (au) |
7.405813 |
| i (deg) |
146.202156 |
| Ω (om, deg) |
228.244773 |
| ω (w, deg) |
244.407920 |
| M (ma, deg) |
0.032314 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.546 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.546 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.800 |
| 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) |
| 2026-07-29 00:00 |
11:41:16.18 |
+33:56:05.3 |
HIP 56997 |
16.29 |
| 2026-07-29 12:00 |
11:41:21.32 |
+33:54:56.7 |
HIP 56959 |
16.63 |
| 2026-07-30 00:00 |
11:41:26.51 |
+33:53:48.3 |
HIP 56959 |
16.37 |
| 2026-07-30 12:00 |
11:41:31.76 |
+33:52:40.0 |
HIP 56959 |
16.26 |
| 2026-07-31 00:00 |
11:41:37.06 |
+33:51:31.9 |
HIP 56959 |
16.31 |
| 2026-07-31 12:00 |
11:41:42.42 |
+33:50:23.9 |
HIP 56959 |
16.53 |
| 2026-08-01 00:00 |
11:41:47.83 |
+33:49:16.1 |
HIP 56959 |
16.90 |
| 2026-08-01 12:00 |
11:41:53.30 |
+33:48:08.4 |
HIP 56959 |
17.43 |
| 2026-08-02 00:00 |
11:41:58.81 |
+33:47:00.8 |
HIP 56959 |
18.10 |
| 2026-08-02 12:00 |
11:42:04.38 |
+33:45:53.4 |
HIP 56959 |
18.88 |
| 2026-08-03 00:00 |
11:42:10.00 |
+33:44:46.2 |
HIP 56959 |
19.79 |
| 2026-08-03 12:00 |
11:42:15.68 |
+33:43:39.1 |
HIP 56959 |
20.79 |
| 2026-08-04 00:00 |
11:42:21.40 |
+33:42:32.2 |
HIP 56959 |
21.87 |
| 2026-08-04 12:00 |
11:42:27.17 |
+33:41:25.5 |
HIP 56959 |
23.04 |
| 2026-08-05 00:00 |
11:42:33.00 |
+33:40:18.9 |
HIP 56959 |
24.26 |
| 2026-08-05 12:00 |
11:42:38.87 |
+33:39:12.6 |
HIP 56959 |
25.55 |
| 2026-08-06 00:00 |
11:42:44.79 |
+33:38:06.4 |
HIP 56959 |
26.88 |
| 2026-08-06 12:00 |
11:42:50.76 |
+33:37:00.4 |
HIP 57308 |
27.54 |
| 2026-08-07 00:00 |
11:42:56.78 |
+33:35:54.6 |
HIP 57308 |
26.21 |
| 2026-08-07 12:00 |
11:43:02.85 |
+33:34:49.0 |
HIP 57308 |
24.92 |
| 2026-08-08 00:00 |
11:43:08.97 |
+33:33:43.6 |
HIP 57308 |
23.65 |
| 2026-08-08 12:00 |
11:43:15.13 |
+33:32:38.4 |
HIP 57308 |
22.44 |
| 2026-08-09 00:00 |
11:43:21.34 |
+33:31:33.5 |
HIP 57308 |
21.27 |
| 2026-08-09 12:00 |
11:43:27.59 |
+33:30:28.7 |
HIP 57308 |
20.17 |
| 2026-08-10 00:00 |
11:43:33.90 |
+33:29:24.2 |
HIP 57308 |
19.14 |
| 2026-08-10 12:00 |
11:43:40.24 |
+33:28:19.8 |
HIP 57308 |
18.21 |
| 2026-08-11 00:00 |
11:43:46.63 |
+33:27:15.8 |
HIP 57308 |
17.38 |
| 2026-08-11 12:00 |
11:43:53.07 |
+33:26:11.9 |
HIP 57308 |
16.67 |
| 2026-08-12 00:00 |
11:43:59.54 |
+33:25:08.3 |
HIP 57308 |
16.11 |
| 2026-08-12 12:00 |
11:44:06.07 |
+33:24:04.9 |
HIP 57308 |
15.70 |
| 2026-08-13 00:00 |
11:44:12.63 |
+33:23:01.8 |
HIP 57308 |
15.46 |
| 2026-08-13 12:00 |
11:44:19.24 |
+33:21:58.9 |
HIP 57308 |
15.41 |
| 2026-08-14 00:00 |
11:44:25.88 |
+33:20:56.3 |
HIP 57308 |
15.54 |
| 2026-08-14 12:00 |
11:44:32.57 |
+33:19:54.0 |
HIP 57308 |
15.86 |
| 2026-08-15 00:00 |
11:44:39.30 |
+33:18:51.9 |
HIP 57308 |
16.35 |
| 2026-08-15 12:00 |
11:44:46.07 |
+33:17:50.1 |
HIP 57308 |
17.00 |
| 2026-08-16 00:00 |
11:44:52.88 |
+33:16:48.6 |
HIP 57308 |
17.79 |
| 2026-08-16 12:00 |
11:44:59.72 |
+33:15:47.3 |
HIP 57308 |
18.70 |
| 2026-08-17 00:00 |
11:45:06.61 |
+33:14:46.3 |
HIP 57308 |
19.73 |
| 2026-08-17 12:00 |
11:45:13.53 |
+33:13:45.6 |
HIP 57308 |
20.85 |
| 2026-08-18 00:00 |
11:45:20.49 |
+33:12:45.3 |
HIP 57308 |
22.05 |
| 2026-08-18 12:00 |
11:45:27.48 |
+33:11:45.2 |
HIP 57308 |
23.32 |
| 2026-08-19 00:00 |
11:45:34.52 |
+33:10:45.4 |
HIP 57308 |
24.65 |