89P/Russell 2
| Parameter |
Value |
| Designation |
89P/Russell 2 |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2016-12-14T20:36:28.673280Z |
| Orbit solution date (soln_date, UTC) |
2025-11-13T13:54:38Z |
| Obs used |
648 |
| NEO |
- |
| M1 |
8.200 |
| K1 |
21.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2018-07-19.0000000 |
| e |
0.40842673 |
| q (au) |
2.220297 |
| a (au) |
3.753208 |
| i (deg) |
12.076267 |
| Ω (om, deg) |
41.443124 |
| ω (w, deg) |
250.178436 |
| M (ma, deg) |
78.773821 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.324 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.324 |
| n |
6.000 |
| gf |
0.856 |
| gb |
-0.758 |
| k |
0.985 |
| 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) |
| 2026-02-03 00:00 |
03:13:17.35 |
+23:22:52.7 |
HIP 15072 |
29.10 |
| 2026-02-03 12:00 |
03:13:25.59 |
+23:23:21.0 |
HIP 15072 |
28.68 |
| 2026-02-04 00:00 |
03:13:34.06 |
+23:23:50.2 |
HIP 15072 |
28.39 |
| 2026-02-04 12:00 |
03:13:42.76 |
+23:24:20.1 |
HIP 15072 |
28.24 |
| 2026-02-05 00:00 |
03:13:51.67 |
+23:24:50.9 |
HIP 15072 |
28.23 |
| 2026-02-05 12:00 |
03:14:00.81 |
+23:25:22.3 |
HIP 15072 |
28.39 |
| 2026-02-06 00:00 |
03:14:10.17 |
+23:25:54.6 |
HIP 15072 |
28.73 |
| 2026-02-06 12:00 |
03:14:19.74 |
+23:26:27.6 |
HIP 15072 |
29.24 |
| 2026-02-07 00:00 |
03:14:29.54 |
+23:27:01.4 |
HIP 15072 |
29.93 |
| 2026-02-07 12:00 |
03:14:39.55 |
+23:27:35.9 |
HIP 15072 |
30.81 |
| 2026-02-08 00:00 |
03:14:49.78 |
+23:28:11.2 |
HIP 15072 |
31.86 |
| 2026-02-08 12:00 |
03:15:00.22 |
+23:28:47.3 |
HIP 15072 |
33.08 |
| 2026-02-09 00:00 |
03:15:10.87 |
+23:29:24.0 |
HIP 15267 |
32.68 |
| 2026-02-09 12:00 |
03:15:21.74 |
+23:30:01.6 |
HIP 15267 |
31.31 |
| 2026-02-10 00:00 |
03:15:32.81 |
+23:30:39.8 |
HIP 15267 |
30.08 |
| 2026-02-10 12:00 |
03:15:44.10 |
+23:31:18.8 |
HIP 15267 |
29.01 |
| 2026-02-11 00:00 |
03:15:55.59 |
+23:31:58.5 |
HIP 15267 |
28.14 |
| 2026-02-11 12:00 |
03:16:07.29 |
+23:32:38.9 |
HIP 15267 |
27.51 |
| 2026-02-12 00:00 |
03:16:19.20 |
+23:33:20.1 |
HIP 15267 |
27.14 |
| 2026-02-12 12:00 |
03:16:31.31 |
+23:34:02.0 |
HIP 15267 |
27.07 |
| 2026-02-13 00:00 |
03:16:43.63 |
+23:34:44.5 |
HIP 15267 |
27.30 |
| 2026-02-13 12:00 |
03:16:56.15 |
+23:35:27.8 |
HIP 15278 |
26.75 |
| 2026-02-14 00:00 |
03:17:08.87 |
+23:36:11.8 |
HIP 15278 |
25.92 |
| 2026-02-14 12:00 |
03:17:21.79 |
+23:36:56.4 |
HIP 15278 |
25.41 |
| 2026-02-15 00:00 |
03:17:34.91 |
+23:37:41.8 |
HIP 15278 |
25.26 |
| 2026-02-15 12:00 |
03:17:48.22 |
+23:38:27.8 |
HIP 15278 |
25.50 |
| 2026-02-16 00:00 |
03:18:01.74 |
+23:39:14.5 |
HIP 15380 |
26.01 |
| 2026-02-16 12:00 |
03:18:15.44 |
+23:40:01.9 |
HIP 15380 |
24.90 |
| 2026-02-17 00:00 |
03:18:29.34 |
+23:40:50.0 |
HIP 15380 |
24.18 |
| 2026-02-17 12:00 |
03:18:43.44 |
+23:41:38.7 |
HIP 15552 |
22.39 |
| 2026-02-18 00:00 |
03:18:57.72 |
+23:42:28.0 |
HIP 15552 |
19.15 |
| 2026-02-18 12:00 |
03:19:12.20 |
+23:43:18.0 |
HIP 15552 |
15.92 |
| 2026-02-19 00:00 |
03:19:26.86 |
+23:44:08.7 |
HIP 15552 |
12.75 |
| 2026-02-19 12:00 |
03:19:41.72 |
+23:45:00.0 |
HIP 15552 |
9.75 |
| 2026-02-20 00:00 |
03:19:56.75 |
+23:45:51.9 |
HIP 15552 |
7.18 |
| 2026-02-20 12:00 |
03:20:11.97 |
+23:46:44.4 |
HIP 15552 |
5.78 |
| 2026-02-21 00:00 |
03:20:27.38 |
+23:47:37.5 |
HIP 15552 |
6.42 |
| 2026-02-21 12:00 |
03:20:42.97 |
+23:48:31.3 |
HIP 15552 |
8.71 |
| 2026-02-22 00:00 |
03:20:58.73 |
+23:49:25.7 |
HIP 15552 |
11.77 |
| 2026-02-22 12:00 |
03:21:14.68 |
+23:50:20.6 |
HIP 15552 |
15.17 |
| 2026-02-23 00:00 |
03:21:30.80 |
+23:51:16.2 |
HIP 15552 |
18.75 |
| 2026-02-23 12:00 |
03:21:47.10 |
+23:52:12.3 |
HIP 15552 |
22.44 |
| 2026-02-24 00:00 |
03:22:03.58 |
+23:53:09.0 |
HIP 15552 |
26.21 |