| Parameter |
Value |
| Designation |
187P/LINEAR |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2008-10-22T14:00:37.010880Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:27:48Z |
| Obs used |
296 |
| NEO |
- |
| M1 |
7.300 |
| K1 |
16.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2011-02-09.0000000 |
| e |
0.17318236 |
| q (au) |
3.715328 |
| a (au) |
4.493528 |
| i (deg) |
13.655086 |
| Ω (om, deg) |
111.736093 |
| ω (w, deg) |
134.735817 |
| M (ma, deg) |
86.856101 |
Magnitude
Scatter + Global Linear
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| 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) |
| 2026-06-01 00:00 |
10:15:24.86 |
+22:05:32.0 |
HIP 50364 |
24.61 |
| 2026-06-01 12:00 |
10:15:41.62 |
+22:03:24.7 |
HIP 50364 |
20.19 |
| 2026-06-02 00:00 |
10:15:58.55 |
+22:01:16.7 |
HIP 50364 |
15.74 |
| 2026-06-02 12:00 |
10:16:15.63 |
+21:59:08.0 |
HIP 50364 |
11.25 |
| 2026-06-03 00:00 |
10:16:32.88 |
+21:56:58.4 |
HIP 50364 |
6.74 |
| 2026-06-03 12:00 |
10:16:50.28 |
+21:54:48.1 |
HIP 50364 |
2.34 |
| 2026-06-04 00:00 |
10:17:07.83 |
+21:52:37.1 |
HIP 50364 |
2.77 |
| 2026-06-04 12:00 |
10:17:25.54 |
+21:50:25.3 |
HIP 50364 |
7.29 |
| 2026-06-05 00:00 |
10:17:43.41 |
+21:48:12.8 |
HIP 50444 |
10.54 |
| 2026-06-05 12:00 |
10:18:01.43 |
+21:45:59.5 |
HIP 50444 |
12.14 |
| 2026-06-06 00:00 |
10:18:19.60 |
+21:43:45.5 |
HIP 50444 |
15.14 |
| 2026-06-06 12:00 |
10:18:37.92 |
+21:41:30.8 |
HIP 50444 |
18.91 |
| 2026-06-07 00:00 |
10:18:56.40 |
+21:39:15.3 |
HIP 50444 |
23.10 |
| 2026-06-07 12:00 |
10:19:15.02 |
+21:36:59.1 |
HIP 50522 |
25.67 |
| 2026-06-08 00:00 |
10:19:33.79 |
+21:34:42.2 |
HIP 50608 |
27.72 |
| 2026-06-08 12:00 |
10:19:52.71 |
+21:32:24.6 |
HIP 50744 |
27.09 |
| 2026-06-09 00:00 |
10:20:11.77 |
+21:30:06.3 |
HIP 50744 |
22.16 |
| 2026-06-09 12:00 |
10:20:30.98 |
+21:27:47.3 |
HIP 50744 |
17.23 |
| 2026-06-10 00:00 |
10:20:50.34 |
+21:25:27.7 |
HIP 50744 |
12.36 |
| 2026-06-10 12:00 |
10:21:09.84 |
+21:23:07.3 |
HIP 50744 |
7.70 |
| 2026-06-11 00:00 |
10:21:29.48 |
+21:20:46.2 |
HIP 50744 |
4.22 |
| 2026-06-11 12:00 |
10:21:49.26 |
+21:18:24.4 |
HIP 50744 |
5.43 |
| 2026-06-12 00:00 |
10:22:09.19 |
+21:16:02.0 |
HIP 50744 |
9.76 |
| 2026-06-12 12:00 |
10:22:29.25 |
+21:13:38.9 |
HIP 50744 |
14.71 |
| 2026-06-13 00:00 |
10:22:49.46 |
+21:11:15.1 |
HIP 50744 |
19.85 |
| 2026-06-13 12:00 |
10:23:09.80 |
+21:08:50.7 |
HIP 50744 |
25.08 |
| 2026-06-14 00:00 |
10:23:30.27 |
+21:06:25.6 |
HIP 50744 |
30.37 |
| 2026-06-14 12:00 |
10:23:50.89 |
+21:03:59.8 |
HIP 50744 |
35.72 |
| 2026-06-15 00:00 |
10:24:11.64 |
+21:01:33.4 |
HIP 50744 |
41.11 |
| 2026-06-15 12:00 |
10:24:32.52 |
+20:59:06.4 |
HIP 50744 |
46.54 |
| 2026-06-16 00:00 |
10:24:53.53 |
+20:56:38.7 |
HIP 51155 |
42.32 |
| 2026-06-16 12:00 |
10:25:14.68 |
+20:54:10.4 |
HIP 51155 |
37.17 |
| 2026-06-17 00:00 |
10:25:35.96 |
+20:51:41.5 |
HIP 51155 |
32.11 |
| 2026-06-17 12:00 |
10:25:57.36 |
+20:49:12.0 |
HIP 51155 |
27.23 |
| 2026-06-18 00:00 |
10:26:18.90 |
+20:46:41.8 |
HIP 51155 |
22.65 |
| 2026-06-18 12:00 |
10:26:40.56 |
+20:44:11.1 |
HIP 51155 |
18.64 |
| 2026-06-19 00:00 |
10:27:02.34 |
+20:41:39.7 |
HIP 51155 |
15.66 |
| 2026-06-19 12:00 |
10:27:24.26 |
+20:39:07.8 |
HIP 51155 |
14.43 |
| 2026-06-20 00:00 |
10:27:46.29 |
+20:36:35.2 |
HIP 51155 |
15.40 |
| 2026-06-20 12:00 |
10:28:08.45 |
+20:34:02.1 |
HIP 51155 |
18.24 |
| 2026-06-21 00:00 |
10:28:30.73 |
+20:31:28.4 |
HIP 51155 |
22.29 |
| 2026-06-21 12:00 |
10:28:53.13 |
+20:28:54.1 |
HIP 51404 |
19.14 |
| 2026-06-22 00:00 |
10:29:15.64 |
+20:26:19.3 |
HIP 51404 |
17.40 |