| Parameter |
Value |
| Designation |
C/1989 Q1 (Okazaki-Levy-Rudenko) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1989-11-11T21:59:23.887680Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:38Z |
| Obs used |
225 |
| NEO |
- |
| M1 |
8.600 |
| K1 |
11.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1989-10-08.0000000 |
| e |
1.00005568 |
| q (au) |
0.642331 |
| a (au) |
-11536.096034 |
| i (deg) |
90.145942 |
| Ω (om, deg) |
275.510071 |
| ω (w, deg) |
150.571089 |
| M (ma, deg) |
-0.000028 |
Magnitude
Scatter + Global Linear
$$
M_a = (7.901 + 2.905\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
7.901 |
| n |
2.905 |
| gf |
0.800 |
| gb |
-1.000 |
| k |
0.800 |
| δ90 |
1.286 |
| 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 |
| 1989-08-24 |
1989-09-13 |
+19.0917 |
-2.707 |
| 1989-09-13 |
1989-11-11 |
-0.2123 |
-0.358 |
| 1989-11-12 |
1990-01-05 |
+1.0681 |
+0.558 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
18:48:29.83 |
-64:22:34.5 |
HIP 92121 |
23.88 |
| 2026-03-26 12:00 |
18:48:30.34 |
-64:22:52.9 |
HIP 92121 |
24.16 |
| 2026-03-27 00:00 |
18:48:30.81 |
-64:23:11.4 |
HIP 92121 |
24.45 |
| 2026-03-27 12:00 |
18:48:31.24 |
-64:23:29.8 |
HIP 92121 |
24.74 |
| 2026-03-28 00:00 |
18:48:31.63 |
-64:23:48.3 |
HIP 92378 |
24.48 |
| 2026-03-28 12:00 |
18:48:31.99 |
-64:24:06.8 |
HIP 92378 |
24.18 |
| 2026-03-29 00:00 |
18:48:32.30 |
-64:24:25.4 |
HIP 92378 |
23.87 |
| 2026-03-29 12:00 |
18:48:32.58 |
-64:24:43.9 |
HIP 92378 |
23.56 |
| 2026-03-30 00:00 |
18:48:32.82 |
-64:25:02.5 |
HIP 92378 |
23.26 |
| 2026-03-30 12:00 |
18:48:33.03 |
-64:25:21.2 |
HIP 92378 |
22.95 |
| 2026-03-31 00:00 |
18:48:33.19 |
-64:25:39.8 |
HIP 92378 |
22.65 |
| 2026-03-31 12:00 |
18:48:33.31 |
-64:25:58.5 |
HIP 92378 |
22.35 |
| 2026-04-01 00:00 |
18:48:33.40 |
-64:26:17.2 |
HIP 92378 |
22.04 |
| 2026-04-01 12:00 |
18:48:33.45 |
-64:26:35.9 |
HIP 92378 |
21.74 |
| 2026-04-02 00:00 |
18:48:33.46 |
-64:26:54.6 |
HIP 92378 |
21.45 |
| 2026-04-02 12:00 |
18:48:33.43 |
-64:27:13.4 |
HIP 92378 |
21.15 |
| 2026-04-03 00:00 |
18:48:33.37 |
-64:27:32.1 |
HIP 92378 |
20.85 |
| 2026-04-03 12:00 |
18:48:33.26 |
-64:27:50.9 |
HIP 92378 |
20.56 |
| 2026-04-04 00:00 |
18:48:33.12 |
-64:28:09.7 |
HIP 92378 |
20.26 |
| 2026-04-04 12:00 |
18:48:32.94 |
-64:28:28.5 |
HIP 92378 |
19.97 |
| 2026-04-05 00:00 |
18:48:32.72 |
-64:28:47.3 |
HIP 92378 |
19.68 |
| 2026-04-05 12:00 |
18:48:32.46 |
-64:29:06.1 |
HIP 92378 |
19.40 |
| 2026-04-06 00:00 |
18:48:32.16 |
-64:29:24.9 |
HIP 92378 |
19.11 |
| 2026-04-06 12:00 |
18:48:31.83 |
-64:29:43.7 |
HIP 92378 |
18.83 |
| 2026-04-07 00:00 |
18:48:31.45 |
-64:30:02.6 |
HIP 92378 |
18.55 |
| 2026-04-07 12:00 |
18:48:31.04 |
-64:30:21.4 |
HIP 92378 |
18.27 |
| 2026-04-08 00:00 |
18:48:30.59 |
-64:30:40.2 |
HIP 92378 |
17.99 |
| 2026-04-08 12:00 |
18:48:30.10 |
-64:30:59.1 |
HIP 92378 |
17.72 |
| 2026-04-09 00:00 |
18:48:29.57 |
-64:31:17.9 |
HIP 92378 |
17.45 |
| 2026-04-09 12:00 |
18:48:29.00 |
-64:31:36.7 |
HIP 92378 |
17.19 |
| 2026-04-10 00:00 |
18:48:28.40 |
-64:31:55.6 |
HIP 92378 |
16.93 |
| 2026-04-10 12:00 |
18:48:27.75 |
-64:32:14.4 |
HIP 92378 |
16.67 |
| 2026-04-11 00:00 |
18:48:27.07 |
-64:32:33.2 |
HIP 92378 |
16.41 |
| 2026-04-11 12:00 |
18:48:26.35 |
-64:32:52.0 |
HIP 92378 |
16.16 |
| 2026-04-12 00:00 |
18:48:25.59 |
-64:33:10.8 |
HIP 92378 |
15.92 |
| 2026-04-12 12:00 |
18:48:24.80 |
-64:33:29.6 |
HIP 92378 |
15.68 |
| 2026-04-13 00:00 |
18:48:23.96 |
-64:33:48.3 |
HIP 92378 |
15.44 |
| 2026-04-13 12:00 |
18:48:23.09 |
-64:34:07.1 |
HIP 92378 |
15.21 |
| 2026-04-14 00:00 |
18:48:22.17 |
-64:34:25.8 |
HIP 92378 |
14.99 |
| 2026-04-14 12:00 |
18:48:21.22 |
-64:34:44.5 |
HIP 92378 |
14.77 |
| 2026-04-15 00:00 |
18:48:20.23 |
-64:35:03.2 |
HIP 92378 |
14.56 |
| 2026-04-15 12:00 |
18:48:19.21 |
-64:35:21.9 |
HIP 92378 |
14.36 |
| 2026-04-16 00:00 |
18:48:18.14 |
-64:35:40.6 |
HIP 92378 |
14.16 |