| Parameter |
Value |
| Designation |
C/1949 K1 (Johnson) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1950-01-19T07:03:40.668480Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:09Z |
| Obs used |
18 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1950-10-11.0000000 |
| e |
1.00071559 |
| q (au) |
2.553079 |
| a (au) |
-3567.814459 |
| i (deg) |
131.351658 |
| Ω (om, deg) |
222.334961 |
| ω (w, deg) |
40.088783 |
| M (ma, deg) |
0.001224 |
Magnitude
Scatter + Global Linear
$$
M_a = (3.685 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
3.685 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.998 |
| 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) |
| 2026-06-01 00:00 |
02:06:40.37 |
-04:11:36.5 |
HIP 9874 |
5.56 |
| 2026-06-01 12:00 |
02:06:41.25 |
-04:11:35.3 |
HIP 9874 |
5.35 |
| 2026-06-02 00:00 |
02:06:42.14 |
-04:11:34.2 |
HIP 9874 |
5.15 |
| 2026-06-02 12:00 |
02:06:43.01 |
-04:11:33.1 |
HIP 9874 |
4.94 |
| 2026-06-03 00:00 |
02:06:43.89 |
-04:11:32.1 |
HIP 9874 |
4.74 |
| 2026-06-03 12:00 |
02:06:44.75 |
-04:11:31.1 |
HIP 9874 |
4.54 |
| 2026-06-04 00:00 |
02:06:45.61 |
-04:11:30.3 |
HIP 9874 |
4.35 |
| 2026-06-04 12:00 |
02:06:46.47 |
-04:11:29.4 |
HIP 9874 |
4.15 |
| 2026-06-05 00:00 |
02:06:47.32 |
-04:11:28.7 |
HIP 9874 |
3.96 |
| 2026-06-05 12:00 |
02:06:48.16 |
-04:11:28.0 |
HIP 9874 |
3.78 |
| 2026-06-06 00:00 |
02:06:48.99 |
-04:11:27.4 |
HIP 9874 |
3.59 |
| 2026-06-06 12:00 |
02:06:49.83 |
-04:11:26.8 |
HIP 9874 |
3.41 |
| 2026-06-07 00:00 |
02:06:50.65 |
-04:11:26.3 |
HIP 9874 |
3.24 |
| 2026-06-07 12:00 |
02:06:51.47 |
-04:11:25.9 |
HIP 9874 |
3.07 |
| 2026-06-08 00:00 |
02:06:52.28 |
-04:11:25.5 |
HIP 9874 |
2.90 |
| 2026-06-08 12:00 |
02:06:53.09 |
-04:11:25.2 |
HIP 9874 |
2.74 |
| 2026-06-09 00:00 |
02:06:53.88 |
-04:11:25.0 |
HIP 9874 |
2.58 |
| 2026-06-09 12:00 |
02:06:54.68 |
-04:11:24.8 |
HIP 9874 |
2.43 |
| 2026-06-10 00:00 |
02:06:55.46 |
-04:11:24.7 |
HIP 9874 |
2.29 |
| 2026-06-10 12:00 |
02:06:56.24 |
-04:11:24.7 |
HIP 9874 |
2.16 |
| 2026-06-11 00:00 |
02:06:57.02 |
-04:11:24.7 |
HIP 9874 |
2.04 |
| 2026-06-11 12:00 |
02:06:57.78 |
-04:11:24.8 |
HIP 9874 |
1.93 |
| 2026-06-12 00:00 |
02:06:58.54 |
-04:11:25.0 |
HIP 9874 |
1.84 |
| 2026-06-12 12:00 |
02:06:59.30 |
-04:11:25.2 |
HIP 9874 |
1.76 |
| 2026-06-13 00:00 |
02:07:00.04 |
-04:11:25.5 |
HIP 9874 |
1.69 |
| 2026-06-13 12:00 |
02:07:00.78 |
-04:11:25.9 |
HIP 9874 |
1.64 |
| 2026-06-14 00:00 |
02:07:01.52 |
-04:11:26.3 |
HIP 9874 |
1.62 |
| 2026-06-14 12:00 |
02:07:02.24 |
-04:11:26.8 |
HIP 9874 |
1.61 |
| 2026-06-15 00:00 |
02:07:02.96 |
-04:11:27.3 |
HIP 9874 |
1.62 |
| 2026-06-15 12:00 |
02:07:03.67 |
-04:11:27.9 |
HIP 9874 |
1.65 |
| 2026-06-16 00:00 |
02:07:04.37 |
-04:11:28.6 |
HIP 9874 |
1.69 |
| 2026-06-16 12:00 |
02:07:05.07 |
-04:11:29.4 |
HIP 9874 |
1.75 |
| 2026-06-17 00:00 |
02:07:05.76 |
-04:11:30.2 |
HIP 9874 |
1.82 |
| 2026-06-17 12:00 |
02:07:06.44 |
-04:11:31.1 |
HIP 9874 |
1.91 |
| 2026-06-18 00:00 |
02:07:07.12 |
-04:11:32.0 |
HIP 9874 |
2.00 |
| 2026-06-18 12:00 |
02:07:07.79 |
-04:11:33.0 |
HIP 9874 |
2.10 |
| 2026-06-19 00:00 |
02:07:08.45 |
-04:11:34.1 |
HIP 9874 |
2.20 |
| 2026-06-19 12:00 |
02:07:09.10 |
-04:11:35.3 |
HIP 9874 |
2.31 |
| 2026-06-20 00:00 |
02:07:09.74 |
-04:11:36.5 |
HIP 9874 |
2.43 |
| 2026-06-20 12:00 |
02:07:10.38 |
-04:11:37.7 |
HIP 9874 |
2.55 |
| 2026-06-21 00:00 |
02:07:11.01 |
-04:11:39.1 |
HIP 9874 |
2.67 |
| 2026-06-21 12:00 |
02:07:11.63 |
-04:11:40.5 |
HIP 9874 |
2.79 |
| 2026-06-22 00:00 |
02:07:12.24 |
-04:11:42.0 |
HIP 9874 |
2.91 |