| Parameter |
Value |
| Designation |
C/1935 A1 (Johnson) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1935-02-26T11:16:10.096320Z |
| Orbit solution date (soln_date, UTC) |
2023-12-04T20:32:30Z |
| Obs used |
34 |
| NEO |
- |
| M1 |
11.200 |
| K1 |
26.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1935-02-28.0000000 |
| e |
0.99129724 |
| q (au) |
0.811142 |
| a (au) |
93.205234 |
| i (deg) |
65.423637 |
| Ω (om, deg) |
92.444706 |
| ω (w, deg) |
18.398934 |
| M (ma, deg) |
0.001676 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.632 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.632 |
| n |
6.000 |
| gf |
0.800 |
| gb |
-0.750 |
| k |
0.800 |
| δ90 |
1.066 |
| 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 |
18:36:01.40 |
-33:46:11.1 |
HIP 91218 |
6.69 |
| 2026-05-12 12:00 |
18:36:00.44 |
-33:46:14.5 |
HIP 91218 |
6.89 |
| 2026-05-13 00:00 |
18:35:59.46 |
-33:46:18.0 |
HIP 91218 |
7.09 |
| 2026-05-13 12:00 |
18:35:58.47 |
-33:46:21.4 |
HIP 91218 |
7.29 |
| 2026-05-14 00:00 |
18:35:57.48 |
-33:46:24.8 |
HIP 91218 |
7.49 |
| 2026-05-14 12:00 |
18:35:56.48 |
-33:46:28.1 |
HIP 91218 |
7.70 |
| 2026-05-15 00:00 |
18:35:55.46 |
-33:46:31.5 |
HIP 91218 |
7.91 |
| 2026-05-15 12:00 |
18:35:54.44 |
-33:46:34.9 |
HIP 91218 |
8.12 |
| 2026-05-16 00:00 |
18:35:53.41 |
-33:46:38.2 |
HIP 91218 |
8.33 |
| 2026-05-16 12:00 |
18:35:52.37 |
-33:46:41.5 |
HIP 91218 |
8.55 |
| 2026-05-17 00:00 |
18:35:51.32 |
-33:46:44.8 |
HIP 91218 |
8.76 |
| 2026-05-17 12:00 |
18:35:50.27 |
-33:46:48.1 |
HIP 91218 |
8.98 |
| 2026-05-18 00:00 |
18:35:49.20 |
-33:46:51.4 |
HIP 91218 |
9.20 |
| 2026-05-18 12:00 |
18:35:48.13 |
-33:46:54.7 |
HIP 91218 |
9.42 |
| 2026-05-19 00:00 |
18:35:47.05 |
-33:46:57.9 |
HIP 91218 |
9.65 |
| 2026-05-19 12:00 |
18:35:45.96 |
-33:47:01.1 |
HIP 91218 |
9.87 |
| 2026-05-20 00:00 |
18:35:44.86 |
-33:47:04.4 |
HIP 91153 |
10.09 |
| 2026-05-20 12:00 |
18:35:43.75 |
-33:47:07.6 |
HIP 91153 |
10.05 |
| 2026-05-21 00:00 |
18:35:42.64 |
-33:47:10.7 |
HIP 91153 |
10.01 |
| 2026-05-21 12:00 |
18:35:41.52 |
-33:47:13.9 |
HIP 91153 |
9.99 |
| 2026-05-22 00:00 |
18:35:40.39 |
-33:47:17.1 |
HIP 91153 |
9.97 |
| 2026-05-22 12:00 |
18:35:39.25 |
-33:47:20.2 |
HIP 91153 |
9.95 |
| 2026-05-23 00:00 |
18:35:38.11 |
-33:47:23.3 |
HIP 91153 |
9.94 |
| 2026-05-23 12:00 |
18:35:36.96 |
-33:47:26.4 |
HIP 91153 |
9.94 |
| 2026-05-24 00:00 |
18:35:35.80 |
-33:47:29.5 |
HIP 91153 |
9.94 |
| 2026-05-24 12:00 |
18:35:34.63 |
-33:47:32.5 |
HIP 91153 |
9.95 |
| 2026-05-25 00:00 |
18:35:33.46 |
-33:47:35.6 |
HIP 91153 |
9.97 |
| 2026-05-25 12:00 |
18:35:32.28 |
-33:47:38.6 |
HIP 91153 |
10.00 |
| 2026-05-26 00:00 |
18:35:31.09 |
-33:47:41.6 |
HIP 91153 |
10.03 |
| 2026-05-26 12:00 |
18:35:29.90 |
-33:47:44.6 |
HIP 91153 |
10.07 |
| 2026-05-27 00:00 |
18:35:28.70 |
-33:47:47.6 |
HIP 91153 |
10.11 |
| 2026-05-27 12:00 |
18:35:27.49 |
-33:47:50.5 |
HIP 91153 |
10.17 |
| 2026-05-28 00:00 |
18:35:26.27 |
-33:47:53.4 |
HIP 91153 |
10.23 |
| 2026-05-28 12:00 |
18:35:25.05 |
-33:47:56.3 |
HIP 91153 |
10.29 |
| 2026-05-29 00:00 |
18:35:23.83 |
-33:47:59.2 |
HIP 91153 |
10.37 |
| 2026-05-29 12:00 |
18:35:22.59 |
-33:48:02.1 |
HIP 91153 |
10.45 |
| 2026-05-30 00:00 |
18:35:21.35 |
-33:48:04.9 |
HIP 91153 |
10.54 |
| 2026-05-30 12:00 |
18:35:20.11 |
-33:48:07.8 |
HIP 91153 |
10.63 |
| 2026-05-31 00:00 |
18:35:18.85 |
-33:48:10.6 |
HIP 91153 |
10.73 |
| 2026-05-31 12:00 |
18:35:17.59 |
-33:48:13.4 |
HIP 91153 |
10.84 |
| 2026-06-01 00:00 |
18:35:16.33 |
-33:48:16.1 |
HIP 91153 |
10.95 |
| 2026-06-01 12:00 |
18:35:15.06 |
-33:48:18.9 |
HIP 91153 |
11.07 |
| 2026-06-02 00:00 |
18:35:13.78 |
-33:48:21.6 |
HIP 91153 |
11.20 |