| Parameter |
Value |
| Designation |
94P/Russell 4 |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2016-10-27T19:11:10.328640Z |
| Orbit solution date (soln_date, UTC) |
2026-05-06T14:49:56Z |
| Obs used |
2200 |
| NEO |
- |
| M1 |
13.400 |
| K1 |
9.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2014-05-04.0000000 |
| e |
0.36414156 |
| q (au) |
2.232637 |
| a (au) |
3.511217 |
| i (deg) |
6.184203 |
| Ω (om, deg) |
70.900127 |
| ω (w, deg) |
92.686863 |
| M (ma, deg) |
224.009846 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.171 + 4.127\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.171 |
| n |
4.127 |
| gf |
1.000 |
| gb |
-0.872 |
| k |
1.000 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2020-09-12 |
2022-11-21 |
+13.1879 |
-4.863 |
| 2022-11-21 |
2023-05-28 |
-4.7545 |
+2.518 |
| 2023-05-28 |
2025-08-16 |
+3.6569 |
-2.522 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
23:16:39.84 |
-10:54:19.1 |
HIP 115031 |
28.15 |
| 2026-05-12 12:00 |
23:16:57.57 |
-10:53:00.6 |
HIP 115031 |
26.68 |
| 2026-05-13 00:00 |
23:17:15.17 |
-10:51:43.0 |
HIP 115031 |
25.92 |
| 2026-05-13 12:00 |
23:17:32.66 |
-10:50:26.2 |
HIP 115031 |
25.92 |
| 2026-05-14 00:00 |
23:17:50.03 |
-10:49:10.4 |
HIP 115031 |
26.67 |
| 2026-05-14 12:00 |
23:18:07.28 |
-10:47:55.5 |
HIP 115031 |
28.10 |
| 2026-05-15 00:00 |
23:18:24.41 |
-10:46:41.4 |
HIP 115031 |
30.09 |
| 2026-05-15 12:00 |
23:18:41.41 |
-10:45:28.3 |
HIP 115031 |
32.52 |
| 2026-05-16 00:00 |
23:18:58.29 |
-10:44:16.1 |
HIP 115278 |
30.71 |
| 2026-05-16 12:00 |
23:19:15.05 |
-10:43:04.8 |
HIP 115278 |
26.46 |
| 2026-05-17 00:00 |
23:19:31.68 |
-10:41:54.5 |
HIP 115278 |
22.27 |
| 2026-05-17 12:00 |
23:19:48.19 |
-10:40:45.1 |
HIP 115278 |
18.15 |
| 2026-05-18 00:00 |
23:20:04.57 |
-10:39:36.7 |
HIP 115278 |
14.11 |
| 2026-05-18 12:00 |
23:20:20.82 |
-10:38:29.2 |
HIP 115278 |
10.21 |
| 2026-05-19 00:00 |
23:20:36.95 |
-10:37:22.6 |
HIP 115278 |
6.68 |
| 2026-05-19 12:00 |
23:20:52.95 |
-10:36:17.1 |
HIP 115278 |
4.33 |
| 2026-05-20 00:00 |
23:21:08.81 |
-10:35:12.4 |
HIP 115278 |
5.12 |
| 2026-05-20 12:00 |
23:21:24.55 |
-10:34:08.8 |
HIP 115278 |
8.11 |
| 2026-05-21 00:00 |
23:21:40.15 |
-10:33:06.1 |
HIP 115278 |
11.70 |
| 2026-05-21 12:00 |
23:21:55.63 |
-10:32:04.4 |
HIP 115278 |
15.45 |
| 2026-05-22 00:00 |
23:22:10.97 |
-10:31:03.7 |
HIP 115278 |
19.24 |
| 2026-05-22 12:00 |
23:22:26.17 |
-10:30:04.0 |
HIP 115445 |
18.43 |
| 2026-05-23 00:00 |
23:22:41.25 |
-10:29:05.3 |
HIP 115445 |
17.76 |
| 2026-05-23 12:00 |
23:22:56.18 |
-10:28:07.6 |
HIP 115445 |
17.89 |
| 2026-05-24 00:00 |
23:23:10.99 |
-10:27:10.8 |
HIP 115445 |
18.78 |
| 2026-05-24 12:00 |
23:23:25.65 |
-10:26:15.1 |
HIP 115445 |
20.31 |
| 2026-05-25 00:00 |
23:23:40.18 |
-10:25:20.4 |
HIP 115445 |
22.33 |
| 2026-05-25 12:00 |
23:23:54.57 |
-10:24:26.7 |
HIP 115445 |
24.71 |
| 2026-05-26 00:00 |
23:24:08.83 |
-10:23:34.0 |
HIP 115445 |
27.34 |
| 2026-05-26 12:00 |
23:24:22.94 |
-10:22:42.4 |
HIP 115445 |
30.13 |
| 2026-05-27 00:00 |
23:24:36.92 |
-10:21:51.8 |
HIP 115445 |
33.04 |
| 2026-05-27 12:00 |
23:24:50.75 |
-10:21:02.2 |
HIP 115712 |
32.17 |
| 2026-05-28 00:00 |
23:25:04.45 |
-10:20:13.6 |
HIP 115712 |
29.00 |
| 2026-05-28 12:00 |
23:25:18.00 |
-10:19:26.1 |
HIP 115712 |
25.95 |
| 2026-05-29 00:00 |
23:25:31.40 |
-10:18:39.6 |
HIP 115712 |
23.04 |
| 2026-05-29 12:00 |
23:25:44.67 |
-10:17:54.2 |
HIP 115712 |
20.32 |
| 2026-05-30 00:00 |
23:25:57.79 |
-10:17:09.8 |
HIP 115712 |
17.84 |
| 2026-05-30 12:00 |
23:26:10.77 |
-10:16:26.5 |
HIP 115712 |
15.70 |
| 2026-05-31 00:00 |
23:26:23.60 |
-10:15:44.3 |
HIP 115712 |
14.04 |
| 2026-05-31 12:00 |
23:26:36.28 |
-10:15:03.1 |
HIP 115712 |
13.00 |
| 2026-06-01 00:00 |
23:26:48.82 |
-10:14:23.1 |
HIP 115712 |
12.72 |
| 2026-06-01 12:00 |
23:27:01.20 |
-10:13:44.0 |
HIP 115712 |
13.20 |
| 2026-06-02 00:00 |
23:27:13.44 |
-10:13:06.1 |
HIP 115712 |
14.35 |