| Parameter |
Value |
| Designation |
C/1947 Y1 (Mrkos) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1948-02-16T15:01:24.922560Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:07Z |
| Obs used |
4 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1948-10-12.0000000 |
| e |
1.00041232 |
| q (au) |
1.499710 |
| a (au) |
-3637.212894 |
| i (deg) |
77.512349 |
| Ω (om, deg) |
199.310414 |
| ω (w, deg) |
61.913458 |
| M (ma, deg) |
0.001071 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.993 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.993 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.777 |
| k |
0.965 |
| 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) |
| 2026-07-29 00:00 |
03:12:25.33 |
-30:57:28.4 |
HIP 14940 |
10.60 |
| 2026-07-29 12:00 |
03:12:25.66 |
-30:57:40.5 |
HIP 14940 |
10.39 |
| 2026-07-30 00:00 |
03:12:25.99 |
-30:57:52.7 |
HIP 14940 |
10.17 |
| 2026-07-30 12:00 |
03:12:26.30 |
-30:58:04.9 |
HIP 14940 |
9.96 |
| 2026-07-31 00:00 |
03:12:26.61 |
-30:58:17.1 |
HIP 14940 |
9.75 |
| 2026-07-31 12:00 |
03:12:26.90 |
-30:58:29.4 |
HIP 14940 |
9.53 |
| 2026-08-01 00:00 |
03:12:27.18 |
-30:58:41.8 |
HIP 14940 |
9.32 |
| 2026-08-01 12:00 |
03:12:27.46 |
-30:58:54.2 |
HIP 14940 |
9.10 |
| 2026-08-02 00:00 |
03:12:27.72 |
-30:59:06.6 |
HIP 14940 |
8.89 |
| 2026-08-02 12:00 |
03:12:27.97 |
-30:59:19.1 |
HIP 14940 |
8.67 |
| 2026-08-03 00:00 |
03:12:28.21 |
-30:59:31.7 |
HIP 14940 |
8.46 |
| 2026-08-03 12:00 |
03:12:28.44 |
-30:59:44.3 |
HIP 14940 |
8.24 |
| 2026-08-04 00:00 |
03:12:28.66 |
-30:59:56.9 |
HIP 14940 |
8.03 |
| 2026-08-04 12:00 |
03:12:28.86 |
-31:00:09.6 |
HIP 14940 |
7.81 |
| 2026-08-05 00:00 |
03:12:29.06 |
-31:00:22.3 |
HIP 14940 |
7.59 |
| 2026-08-05 12:00 |
03:12:29.25 |
-31:00:35.1 |
HIP 14940 |
7.38 |
| 2026-08-06 00:00 |
03:12:29.42 |
-31:00:47.9 |
HIP 14940 |
7.16 |
| 2026-08-06 12:00 |
03:12:29.59 |
-31:01:00.7 |
HIP 14940 |
6.94 |
| 2026-08-07 00:00 |
03:12:29.74 |
-31:01:13.6 |
HIP 14940 |
6.73 |
| 2026-08-07 12:00 |
03:12:29.88 |
-31:01:26.6 |
HIP 14940 |
6.51 |
| 2026-08-08 00:00 |
03:12:30.02 |
-31:01:39.5 |
HIP 14940 |
6.30 |
| 2026-08-08 12:00 |
03:12:30.14 |
-31:01:52.6 |
HIP 14940 |
6.08 |
| 2026-08-09 00:00 |
03:12:30.25 |
-31:02:05.6 |
HIP 14940 |
5.86 |
| 2026-08-09 12:00 |
03:12:30.34 |
-31:02:18.7 |
HIP 14940 |
5.65 |
| 2026-08-10 00:00 |
03:12:30.43 |
-31:02:31.8 |
HIP 14940 |
5.43 |
| 2026-08-10 12:00 |
03:12:30.51 |
-31:02:45.0 |
HIP 14940 |
5.22 |
| 2026-08-11 00:00 |
03:12:30.57 |
-31:02:58.1 |
HIP 14940 |
5.00 |
| 2026-08-11 12:00 |
03:12:30.63 |
-31:03:11.4 |
HIP 14940 |
4.79 |
| 2026-08-12 00:00 |
03:12:30.67 |
-31:03:24.6 |
HIP 14940 |
4.58 |
| 2026-08-12 12:00 |
03:12:30.70 |
-31:03:37.9 |
HIP 14940 |
4.37 |
| 2026-08-13 00:00 |
03:12:30.72 |
-31:03:51.2 |
HIP 14940 |
4.16 |
| 2026-08-13 12:00 |
03:12:30.73 |
-31:04:04.5 |
HIP 14940 |
3.95 |
| 2026-08-14 00:00 |
03:12:30.73 |
-31:04:17.9 |
HIP 14940 |
3.74 |
| 2026-08-14 12:00 |
03:12:30.72 |
-31:04:31.3 |
HIP 14940 |
3.54 |
| 2026-08-15 00:00 |
03:12:30.70 |
-31:04:44.7 |
HIP 14940 |
3.34 |
| 2026-08-15 12:00 |
03:12:30.66 |
-31:04:58.1 |
HIP 14940 |
3.14 |
| 2026-08-16 00:00 |
03:12:30.62 |
-31:05:11.6 |
HIP 14940 |
2.95 |
| 2026-08-16 12:00 |
03:12:30.56 |
-31:05:25.1 |
HIP 14940 |
2.76 |
| 2026-08-17 00:00 |
03:12:30.49 |
-31:05:38.6 |
HIP 14940 |
2.59 |
| 2026-08-17 12:00 |
03:12:30.41 |
-31:05:52.1 |
HIP 14940 |
2.42 |
| 2026-08-18 00:00 |
03:12:30.32 |
-31:06:05.7 |
HIP 14940 |
2.26 |
| 2026-08-18 12:00 |
03:12:30.22 |
-31:06:19.2 |
HIP 14940 |
2.11 |
| 2026-08-19 00:00 |
03:12:30.11 |
-31:06:32.8 |
HIP 14940 |
1.99 |