87P/Bus
| Parameter |
Value |
| Designation |
87P/Bus |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2013-12-19T21:38:08.010240Z |
| Orbit solution date (soln_date, UTC) |
2020-09-28T09:20:31Z |
| Obs used |
667 |
| NEO |
- |
| M1 |
12.700 |
| K1 |
14.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2016-03-20.0000000 |
| e |
0.38934769 |
| q (au) |
2.101175 |
| a (au) |
3.440869 |
| i (deg) |
2.602394 |
| Ω (om, deg) |
181.889806 |
| ω (w, deg) |
24.756386 |
| M (ma, deg) |
126.793522 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.080 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.080 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.756 |
| k |
0.993 |
| 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) |
| 2026-02-03 00:00 |
05:45:33.92 |
+18:58:56.5 |
HIP 27218 |
10.95 |
| 2026-02-03 12:00 |
05:45:25.39 |
+18:59:16.2 |
HIP 27218 |
12.72 |
| 2026-02-04 00:00 |
05:45:17.07 |
+18:59:36.1 |
HIP 27191 |
14.25 |
| 2026-02-04 12:00 |
05:45:08.95 |
+18:59:56.1 |
HIP 27191 |
15.63 |
| 2026-02-05 00:00 |
05:45:01.04 |
+19:00:16.4 |
HIP 27191 |
17.08 |
| 2026-02-05 12:00 |
05:44:53.34 |
+19:00:36.8 |
HIP 27191 |
18.59 |
| 2026-02-06 00:00 |
05:44:45.84 |
+19:00:57.4 |
HIP 27129 |
19.66 |
| 2026-02-06 12:00 |
05:44:38.55 |
+19:01:18.1 |
HIP 27129 |
20.58 |
| 2026-02-07 00:00 |
05:44:31.47 |
+19:01:39.0 |
HIP 27129 |
21.58 |
| 2026-02-07 12:00 |
05:44:24.60 |
+19:02:00.1 |
HIP 26925 |
21.73 |
| 2026-02-08 00:00 |
05:44:17.94 |
+19:02:21.4 |
HIP 26925 |
20.23 |
| 2026-02-08 12:00 |
05:44:11.49 |
+19:02:42.8 |
HIP 26925 |
18.80 |
| 2026-02-09 00:00 |
05:44:05.26 |
+19:03:04.4 |
HIP 26925 |
17.44 |
| 2026-02-09 12:00 |
05:43:59.24 |
+19:03:26.2 |
HIP 26925 |
16.17 |
| 2026-02-10 00:00 |
05:43:53.43 |
+19:03:48.1 |
HIP 26925 |
14.97 |
| 2026-02-10 12:00 |
05:43:47.83 |
+19:04:10.2 |
HIP 26925 |
13.87 |
| 2026-02-11 00:00 |
05:43:42.46 |
+19:04:32.4 |
HIP 26925 |
12.87 |
| 2026-02-11 12:00 |
05:43:37.29 |
+19:04:54.8 |
HIP 26925 |
11.97 |
| 2026-02-12 00:00 |
05:43:32.35 |
+19:05:17.4 |
HIP 26925 |
11.20 |
| 2026-02-12 12:00 |
05:43:27.62 |
+19:05:40.1 |
HIP 26925 |
10.55 |
| 2026-02-13 00:00 |
05:43:23.10 |
+19:06:03.0 |
HIP 26925 |
10.03 |
| 2026-02-13 12:00 |
05:43:18.81 |
+19:06:26.1 |
HIP 26925 |
9.65 |
| 2026-02-14 00:00 |
05:43:14.73 |
+19:06:49.3 |
HIP 26925 |
9.42 |
| 2026-02-14 12:00 |
05:43:10.88 |
+19:07:12.6 |
HIP 26925 |
9.32 |
| 2026-02-15 00:00 |
05:43:07.24 |
+19:07:36.1 |
HIP 26925 |
9.34 |
| 2026-02-15 12:00 |
05:43:03.82 |
+19:07:59.7 |
HIP 26925 |
9.48 |
| 2026-02-16 00:00 |
05:43:00.62 |
+19:08:23.5 |
HIP 26925 |
9.71 |
| 2026-02-16 12:00 |
05:42:57.64 |
+19:08:47.4 |
HIP 26925 |
10.01 |
| 2026-02-17 00:00 |
05:42:54.88 |
+19:09:11.5 |
HIP 26925 |
10.37 |
| 2026-02-17 12:00 |
05:42:52.34 |
+19:09:35.7 |
HIP 26925 |
10.78 |
| 2026-02-18 00:00 |
05:42:50.02 |
+19:10:00.0 |
HIP 26925 |
11.21 |
| 2026-02-18 12:00 |
05:42:47.92 |
+19:10:24.5 |
HIP 26925 |
11.66 |
| 2026-02-19 00:00 |
05:42:46.05 |
+19:10:49.1 |
HIP 26925 |
12.13 |
| 2026-02-19 12:00 |
05:42:44.39 |
+19:11:13.8 |
HIP 26886 |
12.53 |
| 2026-02-20 00:00 |
05:42:42.95 |
+19:11:38.7 |
HIP 26886 |
12.83 |
| 2026-02-20 12:00 |
05:42:41.74 |
+19:12:03.6 |
HIP 26886 |
13.16 |
| 2026-02-21 00:00 |
05:42:40.75 |
+19:12:28.7 |
HIP 26886 |
13.52 |
| 2026-02-21 12:00 |
05:42:39.97 |
+19:12:53.9 |
HIP 26886 |
13.89 |
| 2026-02-22 00:00 |
05:42:39.42 |
+19:13:19.2 |
HIP 26886 |
14.28 |
| 2026-02-22 12:00 |
05:42:39.08 |
+19:13:44.7 |
HIP 26886 |
14.69 |
| 2026-02-23 00:00 |
05:42:38.97 |
+19:14:10.2 |
HIP 26826 |
14.83 |
| 2026-02-23 12:00 |
05:42:39.08 |
+19:14:35.8 |
HIP 26826 |
14.65 |
| 2026-02-24 00:00 |
05:42:39.40 |
+19:15:01.6 |
HIP 26826 |
14.52 |