| Parameter |
Value |
| Designation |
C/1980 O1 (Cernis-Petrauskas) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1980-06-22T10:43:23.995200Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:29Z |
| Obs used |
20 |
| NEO |
- |
| M1 |
9.700 |
| K1 |
8.750 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1980-08-29.0000000 |
| e |
1.00000000 |
| q (au) |
0.522897 |
| a (au) |
- |
| i (deg) |
49.068235 |
| Ω (om, deg) |
160.632533 |
| ω (w, deg) |
337.783670 |
| M (ma, deg) |
- |
Magnitude
Scatter + Global Linear
$$
M_a = (7.470 + 3.779\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
7.470 |
| n |
3.779 |
| gf |
0.800 |
| gb |
-0.501 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
20:52:35.31 |
+07:17:39.9 |
HIP 102997 |
19.03 |
| 2026-09-20 12:00 |
20:52:34.24 |
+07:17:27.9 |
HIP 102997 |
19.11 |
| 2026-09-21 00:00 |
20:52:33.17 |
+07:17:15.8 |
HIP 102997 |
19.19 |
| 2026-09-21 12:00 |
20:52:32.12 |
+07:17:03.7 |
HIP 102997 |
19.28 |
| 2026-09-22 00:00 |
20:52:31.08 |
+07:16:51.6 |
HIP 102997 |
19.37 |
| 2026-09-22 12:00 |
20:52:30.05 |
+07:16:39.5 |
HIP 102997 |
19.47 |
| 2026-09-23 00:00 |
20:52:29.03 |
+07:16:27.4 |
HIP 102997 |
19.57 |
| 2026-09-23 12:00 |
20:52:28.02 |
+07:16:15.2 |
HIP 102997 |
19.69 |
| 2026-09-24 00:00 |
20:52:27.02 |
+07:16:03.1 |
HIP 102997 |
19.80 |
| 2026-09-24 12:00 |
20:52:26.03 |
+07:15:50.9 |
HIP 102997 |
19.93 |
| 2026-09-25 00:00 |
20:52:25.05 |
+07:15:38.7 |
HIP 102997 |
20.05 |
| 2026-09-25 12:00 |
20:52:24.09 |
+07:15:26.5 |
HIP 102997 |
20.19 |
| 2026-09-26 00:00 |
20:52:23.13 |
+07:15:14.3 |
HIP 102997 |
20.32 |
| 2026-09-26 12:00 |
20:52:22.19 |
+07:15:02.0 |
HIP 102997 |
20.47 |
| 2026-09-27 00:00 |
20:52:21.25 |
+07:14:49.8 |
HIP 102997 |
20.61 |
| 2026-09-27 12:00 |
20:52:20.33 |
+07:14:37.5 |
HIP 102997 |
20.76 |
| 2026-09-28 00:00 |
20:52:19.42 |
+07:14:25.3 |
HIP 102997 |
20.92 |
| 2026-09-28 12:00 |
20:52:18.52 |
+07:14:13.0 |
HIP 102997 |
21.08 |
| 2026-09-29 00:00 |
20:52:17.63 |
+07:14:00.7 |
HIP 102997 |
21.24 |
| 2026-09-29 12:00 |
20:52:16.75 |
+07:13:48.5 |
HIP 102923 |
21.23 |
| 2026-09-30 00:00 |
20:52:15.89 |
+07:13:36.2 |
HIP 102923 |
20.94 |
| 2026-09-30 12:00 |
20:52:15.03 |
+07:13:23.9 |
HIP 102923 |
20.64 |
| 2026-10-01 00:00 |
20:52:14.19 |
+07:13:11.6 |
HIP 102923 |
20.36 |
| 2026-10-01 12:00 |
20:52:13.36 |
+07:12:59.3 |
HIP 102923 |
20.07 |
| 2026-10-02 00:00 |
20:52:12.54 |
+07:12:47.0 |
HIP 102923 |
19.79 |
| 2026-10-02 12:00 |
20:52:11.74 |
+07:12:34.7 |
HIP 102923 |
19.51 |
| 2026-10-03 00:00 |
20:52:10.94 |
+07:12:22.4 |
HIP 102923 |
19.23 |
| 2026-10-03 12:00 |
20:52:10.16 |
+07:12:10.1 |
HIP 102923 |
18.95 |
| 2026-10-04 00:00 |
20:52:09.39 |
+07:11:57.8 |
HIP 102923 |
18.68 |
| 2026-10-04 12:00 |
20:52:08.63 |
+07:11:45.5 |
HIP 102923 |
18.41 |
| 2026-10-05 00:00 |
20:52:07.88 |
+07:11:33.2 |
HIP 102923 |
18.14 |
| 2026-10-05 12:00 |
20:52:07.15 |
+07:11:20.9 |
HIP 102923 |
17.88 |
| 2026-10-06 00:00 |
20:52:06.43 |
+07:11:08.6 |
HIP 102923 |
17.62 |
| 2026-10-06 12:00 |
20:52:05.72 |
+07:10:56.3 |
HIP 102923 |
17.36 |
| 2026-10-07 00:00 |
20:52:05.02 |
+07:10:44.1 |
HIP 102923 |
17.11 |
| 2026-10-07 12:00 |
20:52:04.34 |
+07:10:31.8 |
HIP 102923 |
16.85 |
| 2026-10-08 00:00 |
20:52:03.66 |
+07:10:19.5 |
HIP 102923 |
16.60 |
| 2026-10-08 12:00 |
20:52:03.00 |
+07:10:07.3 |
HIP 102923 |
16.36 |
| 2026-10-09 00:00 |
20:52:02.36 |
+07:09:55.1 |
HIP 102923 |
16.12 |
| 2026-10-09 12:00 |
20:52:01.72 |
+07:09:42.9 |
HIP 102923 |
15.88 |
| 2026-10-10 00:00 |
20:52:01.10 |
+07:09:30.6 |
HIP 102923 |
15.64 |
| 2026-10-10 12:00 |
20:52:00.50 |
+07:09:18.5 |
HIP 102923 |
15.41 |
| 2026-10-11 00:00 |
20:51:59.90 |
+07:09:06.3 |
HIP 102923 |
15.18 |