48P/Johnson
| Parameter |
Value |
| Designation |
48P/Johnson |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2018-08-12T05:19:55.133760Z |
| Orbit solution date (soln_date, UTC) |
2026-01-13T17:41:36Z |
| Obs used |
2187 |
| NEO |
- |
| M1 |
9.100 |
| K1 |
16.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2019-02-17.0000000 |
| e |
0.42706134 |
| q (au) |
2.004537 |
| a (au) |
3.498694 |
| i (deg) |
12.206975 |
| Ω (om, deg) |
110.131541 |
| ω (w, deg) |
216.571834 |
| M (ma, deg) |
28.431257 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.633 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.633 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.870 |
| 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) |
| 2026-02-03 00:00 |
03:16:05.05 |
+08:46:35.3 |
HIP 15099 |
22.88 |
| 2026-02-03 12:00 |
03:16:22.76 |
+08:50:07.1 |
HIP 15298 |
21.92 |
| 2026-02-04 00:00 |
03:16:40.70 |
+08:53:38.9 |
HIP 15298 |
16.35 |
| 2026-02-04 12:00 |
03:16:58.88 |
+08:57:10.9 |
HIP 15298 |
10.86 |
| 2026-02-05 00:00 |
03:17:17.28 |
+09:00:42.8 |
HIP 15298 |
5.78 |
| 2026-02-05 12:00 |
03:17:35.91 |
+09:04:14.8 |
HIP 15298 |
3.95 |
| 2026-02-06 00:00 |
03:17:54.78 |
+09:07:46.8 |
HIP 15298 |
8.12 |
| 2026-02-06 12:00 |
03:18:13.86 |
+09:11:18.8 |
HIP 15374 |
3.41 |
| 2026-02-07 00:00 |
03:18:33.17 |
+09:14:50.8 |
HIP 15374 |
4.48 |
| 2026-02-07 12:00 |
03:18:52.70 |
+09:18:22.7 |
HIP 15374 |
9.99 |
| 2026-02-08 00:00 |
03:19:12.46 |
+09:21:54.7 |
HIP 15374 |
15.89 |
| 2026-02-08 12:00 |
03:19:32.43 |
+09:25:26.6 |
HIP 15374 |
21.91 |
| 2026-02-09 00:00 |
03:19:52.62 |
+09:28:58.5 |
HIP 15630 |
23.44 |
| 2026-02-09 12:00 |
03:20:13.02 |
+09:32:30.3 |
HIP 15630 |
17.38 |
| 2026-02-10 00:00 |
03:20:33.64 |
+09:36:02.1 |
HIP 15630 |
11.35 |
| 2026-02-10 12:00 |
03:20:54.47 |
+09:39:33.8 |
HIP 15630 |
5.65 |
| 2026-02-11 00:00 |
03:21:15.52 |
+09:43:05.4 |
HIP 15630 |
3.53 |
| 2026-02-11 12:00 |
03:21:36.77 |
+09:46:36.9 |
HIP 15630 |
8.49 |
| 2026-02-12 00:00 |
03:21:58.23 |
+09:50:08.4 |
HIP 15630 |
14.58 |
| 2026-02-12 12:00 |
03:22:19.90 |
+09:53:39.7 |
HIP 15630 |
20.86 |
| 2026-02-13 00:00 |
03:22:41.77 |
+09:57:10.9 |
HIP 15630 |
27.23 |
| 2026-02-13 12:00 |
03:23:03.85 |
+10:00:42.0 |
HIP 15897 |
28.02 |
| 2026-02-14 00:00 |
03:23:26.13 |
+10:04:12.9 |
HIP 15918 |
23.22 |
| 2026-02-14 12:00 |
03:23:48.60 |
+10:07:43.8 |
HIP 15918 |
18.80 |
| 2026-02-15 00:00 |
03:24:11.28 |
+10:11:14.4 |
HIP 15918 |
15.90 |
| 2026-02-15 12:00 |
03:24:34.16 |
+10:14:44.9 |
HIP 15918 |
15.44 |
| 2026-02-16 00:00 |
03:24:57.23 |
+10:18:15.3 |
HIP 15837 |
17.03 |
| 2026-02-16 12:00 |
03:25:20.49 |
+10:21:45.4 |
HIP 15837 |
20.76 |
| 2026-02-17 00:00 |
03:25:43.95 |
+10:25:15.4 |
HIP 15837 |
25.77 |
| 2026-02-17 12:00 |
03:26:07.60 |
+10:28:45.2 |
HIP 15837 |
31.48 |
| 2026-02-18 00:00 |
03:26:31.44 |
+10:32:14.7 |
HIP 15922 |
33.90 |
| 2026-02-18 12:00 |
03:26:55.46 |
+10:35:44.1 |
HIP 15922 |
35.55 |
| 2026-02-19 00:00 |
03:27:19.67 |
+10:39:13.2 |
HIP 16250 |
34.22 |
| 2026-02-19 12:00 |
03:27:44.07 |
+10:42:42.1 |
HIP 16250 |
27.31 |
| 2026-02-20 00:00 |
03:28:08.65 |
+10:46:10.7 |
HIP 16250 |
20.39 |
| 2026-02-20 12:00 |
03:28:33.41 |
+10:49:39.1 |
HIP 16250 |
13.47 |
| 2026-02-21 00:00 |
03:28:58.35 |
+10:53:07.3 |
HIP 16250 |
6.67 |
| 2026-02-21 12:00 |
03:29:23.47 |
+10:56:35.2 |
HIP 16250 |
2.59 |
| 2026-02-22 00:00 |
03:29:48.76 |
+11:00:02.7 |
HIP 16250 |
8.33 |
| 2026-02-22 12:00 |
03:30:14.23 |
+11:03:30.1 |
HIP 16250 |
15.30 |
| 2026-02-23 00:00 |
03:30:39.88 |
+11:06:57.1 |
HIP 16322 |
13.77 |
| 2026-02-23 12:00 |
03:31:05.69 |
+11:10:23.8 |
HIP 16322 |
14.07 |
| 2026-02-24 00:00 |
03:31:31.67 |
+11:13:50.2 |
HIP 16322 |
17.66 |