| Parameter |
Value |
| Designation |
C/1974 O1 (Cesco) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1974-05-12T23:37:48.135360Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:22Z |
| Obs used |
18 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1974-08-21.0000000 |
| e |
0.97938205 |
| q (au) |
1.372893 |
| a (au) |
66.587290 |
| i (deg) |
173.158463 |
| Ω (om, deg) |
165.740646 |
| ω (w, deg) |
176.764065 |
| M (ma, deg) |
0.181420 |
Magnitude
Scatter + Global Linear
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| 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) |
| 2026-03-26 00:00 |
11:58:37.14 |
-01:46:30.7 |
HIP 58480 |
16.61 |
| 2026-03-26 12:00 |
11:58:35.46 |
-01:46:19.6 |
HIP 58480 |
17.06 |
| 2026-03-27 00:00 |
11:58:33.78 |
-01:46:08.5 |
HIP 58480 |
17.52 |
| 2026-03-27 12:00 |
11:58:32.11 |
-01:45:57.5 |
HIP 58480 |
17.97 |
| 2026-03-28 00:00 |
11:58:30.43 |
-01:45:46.4 |
HIP 58480 |
18.43 |
| 2026-03-28 12:00 |
11:58:28.76 |
-01:45:35.3 |
HIP 58480 |
18.88 |
| 2026-03-29 00:00 |
11:58:27.09 |
-01:45:24.3 |
HIP 58480 |
19.33 |
| 2026-03-29 12:00 |
11:58:25.42 |
-01:45:13.2 |
HIP 58480 |
19.79 |
| 2026-03-30 00:00 |
11:58:23.75 |
-01:45:02.2 |
HIP 58480 |
20.24 |
| 2026-03-30 12:00 |
11:58:22.09 |
-01:44:51.2 |
HIP 58480 |
20.69 |
| 2026-03-31 00:00 |
11:58:20.42 |
-01:44:40.1 |
HIP 58480 |
21.14 |
| 2026-03-31 12:00 |
11:58:18.76 |
-01:44:29.1 |
HIP 58480 |
21.59 |
| 2026-04-01 00:00 |
11:58:17.11 |
-01:44:18.1 |
HIP 58480 |
22.04 |
| 2026-04-01 12:00 |
11:58:15.45 |
-01:44:07.1 |
HIP 58480 |
22.49 |
| 2026-04-02 00:00 |
11:58:13.80 |
-01:43:56.2 |
HIP 58480 |
22.94 |
| 2026-04-02 12:00 |
11:58:12.16 |
-01:43:45.2 |
HIP 58480 |
23.39 |
| 2026-04-03 00:00 |
11:58:10.51 |
-01:43:34.2 |
HIP 58480 |
23.84 |
| 2026-04-03 12:00 |
11:58:08.87 |
-01:43:23.3 |
HIP 58480 |
24.29 |
| 2026-04-04 00:00 |
11:58:07.24 |
-01:43:12.4 |
HIP 58480 |
24.73 |
| 2026-04-04 12:00 |
11:58:05.60 |
-01:43:01.5 |
HIP 58480 |
25.18 |
| 2026-04-05 00:00 |
11:58:03.97 |
-01:42:50.6 |
HIP 58480 |
25.62 |
| 2026-04-05 12:00 |
11:58:02.35 |
-01:42:39.7 |
HIP 58480 |
26.07 |
| 2026-04-06 00:00 |
11:58:00.72 |
-01:42:28.8 |
HIP 58480 |
26.51 |
| 2026-04-06 12:00 |
11:57:59.11 |
-01:42:18.0 |
HIP 58480 |
26.95 |
| 2026-04-07 00:00 |
11:57:57.49 |
-01:42:07.2 |
HIP 58480 |
27.39 |
| 2026-04-07 12:00 |
11:57:55.88 |
-01:41:56.4 |
HIP 58480 |
27.83 |
| 2026-04-08 00:00 |
11:57:54.28 |
-01:41:45.6 |
HIP 58480 |
28.27 |
| 2026-04-08 12:00 |
11:57:52.68 |
-01:41:34.9 |
HIP 58480 |
28.71 |
| 2026-04-09 00:00 |
11:57:51.08 |
-01:41:24.1 |
HIP 58480 |
29.14 |
| 2026-04-09 12:00 |
11:57:49.49 |
-01:41:13.4 |
HIP 58480 |
29.58 |
| 2026-04-10 00:00 |
11:57:47.91 |
-01:41:02.7 |
HIP 58480 |
30.01 |
| 2026-04-10 12:00 |
11:57:46.33 |
-01:40:52.1 |
HIP 58191 |
29.92 |
| 2026-04-11 00:00 |
11:57:44.75 |
-01:40:41.5 |
HIP 58191 |
29.49 |
| 2026-04-11 12:00 |
11:57:43.18 |
-01:40:30.8 |
HIP 58191 |
29.06 |
| 2026-04-12 00:00 |
11:57:41.61 |
-01:40:20.3 |
HIP 58191 |
28.63 |
| 2026-04-12 12:00 |
11:57:40.05 |
-01:40:09.7 |
HIP 58191 |
28.21 |
| 2026-04-13 00:00 |
11:57:38.50 |
-01:39:59.2 |
HIP 58191 |
27.78 |
| 2026-04-13 12:00 |
11:57:36.95 |
-01:39:48.7 |
HIP 58191 |
27.36 |
| 2026-04-14 00:00 |
11:57:35.41 |
-01:39:38.3 |
HIP 58191 |
26.94 |
| 2026-04-14 12:00 |
11:57:33.87 |
-01:39:27.8 |
HIP 58191 |
26.52 |
| 2026-04-15 00:00 |
11:57:32.34 |
-01:39:17.4 |
HIP 58191 |
26.10 |
| 2026-04-15 12:00 |
11:57:30.82 |
-01:39:07.1 |
HIP 58191 |
25.68 |
| 2026-04-16 00:00 |
11:57:29.30 |
-01:38:56.7 |
HIP 58191 |
25.27 |