| Parameter |
Value |
| Designation |
C/1956 E1 (Mrkos) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1956-04-13T14:37:14.880000Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:12Z |
| Obs used |
4 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1956-04-05.0000000 |
| e |
1.00000000 |
| q (au) |
0.842240 |
| a (au) |
- |
| i (deg) |
147.451900 |
| Ω (om, deg) |
226.715900 |
| ω (w, deg) |
81.001500 |
| M (ma, deg) |
- |
Magnitude
Scatter + Global Linear
$$
M_a = (9.975 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.975 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.938 |
| 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) |
| 2026-05-12 00:00 |
23:42:27.81 |
-35:15:46.3 |
HIP 116903 |
8.87 |
| 2026-05-12 12:00 |
23:42:28.58 |
-35:15:51.3 |
HIP 116903 |
9.04 |
| 2026-05-13 00:00 |
23:42:29.35 |
-35:15:56.5 |
HIP 116903 |
9.22 |
| 2026-05-13 12:00 |
23:42:30.10 |
-35:16:01.7 |
HIP 116903 |
9.39 |
| 2026-05-14 00:00 |
23:42:30.85 |
-35:16:07.0 |
HIP 116903 |
9.56 |
| 2026-05-14 12:00 |
23:42:31.58 |
-35:16:12.4 |
HIP 116903 |
9.74 |
| 2026-05-15 00:00 |
23:42:32.31 |
-35:16:17.9 |
HIP 116903 |
9.91 |
| 2026-05-15 12:00 |
23:42:33.03 |
-35:16:23.5 |
HIP 116903 |
10.07 |
| 2026-05-16 00:00 |
23:42:33.73 |
-35:16:29.2 |
HIP 116903 |
10.24 |
| 2026-05-16 12:00 |
23:42:34.43 |
-35:16:35.0 |
HIP 116903 |
10.41 |
| 2026-05-17 00:00 |
23:42:35.11 |
-35:16:40.9 |
HIP 116903 |
10.57 |
| 2026-05-17 12:00 |
23:42:35.79 |
-35:16:46.8 |
HIP 116903 |
10.74 |
| 2026-05-18 00:00 |
23:42:36.45 |
-35:16:52.9 |
HIP 116903 |
10.90 |
| 2026-05-18 12:00 |
23:42:37.11 |
-35:16:59.0 |
HIP 116903 |
11.06 |
| 2026-05-19 00:00 |
23:42:37.75 |
-35:17:05.2 |
HIP 116903 |
11.22 |
| 2026-05-19 12:00 |
23:42:38.38 |
-35:17:11.5 |
HIP 116903 |
11.38 |
| 2026-05-20 00:00 |
23:42:39.01 |
-35:17:17.9 |
HIP 116903 |
11.54 |
| 2026-05-20 12:00 |
23:42:39.62 |
-35:17:24.4 |
HIP 116903 |
11.69 |
| 2026-05-21 00:00 |
23:42:40.22 |
-35:17:31.0 |
HIP 116903 |
11.85 |
| 2026-05-21 12:00 |
23:42:40.81 |
-35:17:37.6 |
HIP 116903 |
12.00 |
| 2026-05-22 00:00 |
23:42:41.40 |
-35:17:44.3 |
HIP 116903 |
12.15 |
| 2026-05-22 12:00 |
23:42:41.97 |
-35:17:51.2 |
HIP 116903 |
12.30 |
| 2026-05-23 00:00 |
23:42:42.53 |
-35:17:58.1 |
HIP 116903 |
12.45 |
| 2026-05-23 12:00 |
23:42:43.07 |
-35:18:05.0 |
HIP 116903 |
12.60 |
| 2026-05-24 00:00 |
23:42:43.61 |
-35:18:12.1 |
HIP 116903 |
12.75 |
| 2026-05-24 12:00 |
23:42:44.14 |
-35:18:19.3 |
HIP 116903 |
12.90 |
| 2026-05-25 00:00 |
23:42:44.66 |
-35:18:26.5 |
HIP 116903 |
13.04 |
| 2026-05-25 12:00 |
23:42:45.16 |
-35:18:33.8 |
HIP 116903 |
13.19 |
| 2026-05-26 00:00 |
23:42:45.66 |
-35:18:41.2 |
HIP 116903 |
13.33 |
| 2026-05-26 12:00 |
23:42:46.14 |
-35:18:48.7 |
HIP 116903 |
13.47 |
| 2026-05-27 00:00 |
23:42:46.61 |
-35:18:56.2 |
HIP 116903 |
13.62 |
| 2026-05-27 12:00 |
23:42:47.08 |
-35:19:03.8 |
HIP 116903 |
13.76 |
| 2026-05-28 00:00 |
23:42:47.53 |
-35:19:11.5 |
HIP 116903 |
13.89 |
| 2026-05-28 12:00 |
23:42:47.97 |
-35:19:19.3 |
HIP 116903 |
14.03 |
| 2026-05-29 00:00 |
23:42:48.40 |
-35:19:27.2 |
HIP 116903 |
14.17 |
| 2026-05-29 12:00 |
23:42:48.81 |
-35:19:35.1 |
HIP 116903 |
14.31 |
| 2026-05-30 00:00 |
23:42:49.22 |
-35:19:43.1 |
HIP 116903 |
14.44 |
| 2026-05-30 12:00 |
23:42:49.62 |
-35:19:51.2 |
HIP 116903 |
14.58 |
| 2026-05-31 00:00 |
23:42:50.00 |
-35:19:59.4 |
HIP 116903 |
14.71 |
| 2026-05-31 12:00 |
23:42:50.38 |
-35:20:07.6 |
HIP 116903 |
14.84 |
| 2026-06-01 00:00 |
23:42:50.74 |
-35:20:16.0 |
HIP 116903 |
14.97 |
| 2026-06-01 12:00 |
23:42:51.09 |
-35:20:24.3 |
HIP 116903 |
15.10 |
| 2026-06-02 00:00 |
23:42:51.43 |
-35:20:32.8 |
HIP 116903 |
15.23 |