| Parameter |
Value |
| Designation |
C/1990 K1 (Levy) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1990-10-24T16:24:53.331840Z |
| Orbit solution date (soln_date, UTC) |
2023-08-19T20:42:31Z |
| Obs used |
666 |
| NEO |
- |
| M1 |
4.600 |
| K1 |
9.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1990-10-29.0000000 |
| e |
1.00058309 |
| q (au) |
0.938738 |
| a (au) |
-1609.945375 |
| i (deg) |
131.583977 |
| Ω (om, deg) |
139.364097 |
| ω (w, deg) |
242.666331 |
| M (ma, deg) |
0.000066 |
Magnitude
Scatter + Global Linear
$$
M_a = (4.561 + 3.402\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
4.561 |
| n |
3.402 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
0.916 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 1990-05-20 |
1990-07-17 |
+0.5609 |
-0.382 |
| 1990-07-17 |
1990-10-23 |
-2.7924 |
+0.454 |
| 1990-10-24 |
1991-04-15 |
+1.4645 |
+0.190 |
| 1991-04-15 |
1991-11-07 |
-5.2198 |
+3.605 |
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 |
07:12:11.44 |
+56:33:06.8 |
HIP 34754 |
15.27 |
| 2026-03-26 12:00 |
07:12:10.64 |
+56:32:51.6 |
HIP 34754 |
15.00 |
| 2026-03-27 00:00 |
07:12:09.86 |
+56:32:36.4 |
HIP 34754 |
14.73 |
| 2026-03-27 12:00 |
07:12:09.12 |
+56:32:21.1 |
HIP 34754 |
14.45 |
| 2026-03-28 00:00 |
07:12:08.40 |
+56:32:05.8 |
HIP 34754 |
14.18 |
| 2026-03-28 12:00 |
07:12:07.72 |
+56:31:50.5 |
HIP 34754 |
13.91 |
| 2026-03-29 00:00 |
07:12:07.06 |
+56:31:35.1 |
HIP 34754 |
13.64 |
| 2026-03-29 12:00 |
07:12:06.44 |
+56:31:19.6 |
HIP 34754 |
13.36 |
| 2026-03-30 00:00 |
07:12:05.85 |
+56:31:04.2 |
HIP 34754 |
13.09 |
| 2026-03-30 12:00 |
07:12:05.29 |
+56:30:48.6 |
HIP 34754 |
12.82 |
| 2026-03-31 00:00 |
07:12:04.75 |
+56:30:33.1 |
HIP 34754 |
12.55 |
| 2026-03-31 12:00 |
07:12:04.25 |
+56:30:17.5 |
HIP 34754 |
12.29 |
| 2026-04-01 00:00 |
07:12:03.78 |
+56:30:01.8 |
HIP 34754 |
12.02 |
| 2026-04-01 12:00 |
07:12:03.34 |
+56:29:46.2 |
HIP 34754 |
11.75 |
| 2026-04-02 00:00 |
07:12:02.93 |
+56:29:30.5 |
HIP 34754 |
11.48 |
| 2026-04-02 12:00 |
07:12:02.55 |
+56:29:14.7 |
HIP 34754 |
11.22 |
| 2026-04-03 00:00 |
07:12:02.20 |
+56:28:59.0 |
HIP 34754 |
10.95 |
| 2026-04-03 12:00 |
07:12:01.89 |
+56:28:43.2 |
HIP 34754 |
10.69 |
| 2026-04-04 00:00 |
07:12:01.60 |
+56:28:27.3 |
HIP 34754 |
10.42 |
| 2026-04-04 12:00 |
07:12:01.34 |
+56:28:11.5 |
HIP 34754 |
10.16 |
| 2026-04-05 00:00 |
07:12:01.11 |
+56:27:55.6 |
HIP 34754 |
9.90 |
| 2026-04-05 12:00 |
07:12:00.92 |
+56:27:39.7 |
HIP 34754 |
9.64 |
| 2026-04-06 00:00 |
07:12:00.75 |
+56:27:23.8 |
HIP 34754 |
9.38 |
| 2026-04-06 12:00 |
07:12:00.61 |
+56:27:07.8 |
HIP 34754 |
9.12 |
| 2026-04-07 00:00 |
07:12:00.51 |
+56:26:51.8 |
HIP 34754 |
8.86 |
| 2026-04-07 12:00 |
07:12:00.43 |
+56:26:35.8 |
HIP 34754 |
8.61 |
| 2026-04-08 00:00 |
07:12:00.38 |
+56:26:19.8 |
HIP 34754 |
8.35 |
| 2026-04-08 12:00 |
07:12:00.37 |
+56:26:03.8 |
HIP 34754 |
8.10 |
| 2026-04-09 00:00 |
07:12:00.38 |
+56:25:47.7 |
HIP 34754 |
7.86 |
| 2026-04-09 12:00 |
07:12:00.43 |
+56:25:31.6 |
HIP 34754 |
7.61 |
| 2026-04-10 00:00 |
07:12:00.50 |
+56:25:15.6 |
HIP 34754 |
7.37 |
| 2026-04-10 12:00 |
07:12:00.61 |
+56:24:59.5 |
HIP 34754 |
7.13 |
| 2026-04-11 00:00 |
07:12:00.74 |
+56:24:43.3 |
HIP 34754 |
6.89 |
| 2026-04-11 12:00 |
07:12:00.91 |
+56:24:27.2 |
HIP 34754 |
6.66 |
| 2026-04-12 00:00 |
07:12:01.11 |
+56:24:11.1 |
HIP 34754 |
6.43 |
| 2026-04-12 12:00 |
07:12:01.33 |
+56:23:54.9 |
HIP 34754 |
6.21 |
| 2026-04-13 00:00 |
07:12:01.59 |
+56:23:38.8 |
HIP 34754 |
6.00 |
| 2026-04-13 12:00 |
07:12:01.87 |
+56:23:22.6 |
HIP 34754 |
5.79 |
| 2026-04-14 00:00 |
07:12:02.19 |
+56:23:06.5 |
HIP 34754 |
5.59 |
| 2026-04-14 12:00 |
07:12:02.53 |
+56:22:50.3 |
HIP 34754 |
5.40 |
| 2026-04-15 00:00 |
07:12:02.91 |
+56:22:34.1 |
HIP 34754 |
5.21 |
| 2026-04-15 12:00 |
07:12:03.31 |
+56:22:18.0 |
HIP 34754 |
5.04 |
| 2026-04-16 00:00 |
07:12:03.75 |
+56:22:01.8 |
HIP 34754 |
4.88 |