C/1941 B1 (Friend-Reese-Honda)
| Parameter |
Value |
| Designation |
C/1941 B1 (Friend-Reese-Honda) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1941-01-20T09:04:01.920000Z |
| Orbit solution date (soln_date, UTC) |
- |
| Obs used |
29 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1941-01-20.3778000 |
| e |
0.98122100 |
| q (au) |
0.941864 |
| a (au) |
50.155173 |
| i (deg) |
26.275600 |
| Ω (om, deg) |
329.789700 |
| ω (w, deg) |
132.731900 |
| M (ma, deg) |
0.000000 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.927 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.927 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.906 |
| 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 |
18:55:45.71 |
-43:17:07.7 |
HIP 92973 |
8.60 |
| 2026-02-03 12:00 |
18:55:47.44 |
-43:17:09.8 |
HIP 92973 |
8.31 |
| 2026-02-04 00:00 |
18:55:49.17 |
-43:17:11.9 |
HIP 92973 |
8.01 |
| 2026-02-04 12:00 |
18:55:50.89 |
-43:17:14.1 |
HIP 92973 |
7.72 |
| 2026-02-05 00:00 |
18:55:52.60 |
-43:17:16.4 |
HIP 92973 |
7.43 |
| 2026-02-05 12:00 |
18:55:54.31 |
-43:17:18.7 |
HIP 92973 |
7.15 |
| 2026-02-06 00:00 |
18:55:56.00 |
-43:17:21.1 |
HIP 92973 |
6.86 |
| 2026-02-06 12:00 |
18:55:57.68 |
-43:17:23.6 |
HIP 92973 |
6.59 |
| 2026-02-07 00:00 |
18:55:59.36 |
-43:17:26.1 |
HIP 92973 |
6.31 |
| 2026-02-07 12:00 |
18:56:01.02 |
-43:17:28.7 |
HIP 92973 |
6.04 |
| 2026-02-08 00:00 |
18:56:02.67 |
-43:17:31.4 |
HIP 92973 |
5.77 |
| 2026-02-08 12:00 |
18:56:04.32 |
-43:17:34.1 |
HIP 92973 |
5.51 |
| 2026-02-09 00:00 |
18:56:05.95 |
-43:17:36.9 |
HIP 92973 |
5.25 |
| 2026-02-09 12:00 |
18:56:07.58 |
-43:17:39.7 |
HIP 92973 |
4.99 |
| 2026-02-10 00:00 |
18:56:09.19 |
-43:17:42.6 |
HIP 92973 |
4.75 |
| 2026-02-10 12:00 |
18:56:10.80 |
-43:17:45.6 |
HIP 92973 |
4.51 |
| 2026-02-11 00:00 |
18:56:12.39 |
-43:17:48.6 |
HIP 92973 |
4.27 |
| 2026-02-11 12:00 |
18:56:13.97 |
-43:17:51.7 |
HIP 92973 |
4.05 |
| 2026-02-12 00:00 |
18:56:15.54 |
-43:17:54.8 |
HIP 92973 |
3.84 |
| 2026-02-12 12:00 |
18:56:17.11 |
-43:17:58.0 |
HIP 92973 |
3.63 |
| 2026-02-13 00:00 |
18:56:18.66 |
-43:18:01.3 |
HIP 92973 |
3.44 |
| 2026-02-13 12:00 |
18:56:20.19 |
-43:18:04.6 |
HIP 92973 |
3.26 |
| 2026-02-14 00:00 |
18:56:21.72 |
-43:18:08.0 |
HIP 92973 |
3.10 |
| 2026-02-14 12:00 |
18:56:23.24 |
-43:18:11.5 |
HIP 92973 |
2.96 |
| 2026-02-15 00:00 |
18:56:24.74 |
-43:18:15.0 |
HIP 92973 |
2.83 |
| 2026-02-15 12:00 |
18:56:26.24 |
-43:18:18.6 |
HIP 92973 |
2.73 |
| 2026-02-16 00:00 |
18:56:27.72 |
-43:18:22.2 |
HIP 92973 |
2.65 |
| 2026-02-16 12:00 |
18:56:29.19 |
-43:18:25.9 |
HIP 92973 |
2.60 |
| 2026-02-17 00:00 |
18:56:30.65 |
-43:18:29.7 |
HIP 92973 |
2.58 |
| 2026-02-17 12:00 |
18:56:32.09 |
-43:18:33.5 |
HIP 92973 |
2.58 |
| 2026-02-18 00:00 |
18:56:33.53 |
-43:18:37.3 |
HIP 92973 |
2.61 |
| 2026-02-18 12:00 |
18:56:34.95 |
-43:18:41.3 |
HIP 92973 |
2.67 |
| 2026-02-19 00:00 |
18:56:36.36 |
-43:18:45.2 |
HIP 92973 |
2.74 |
| 2026-02-19 12:00 |
18:56:37.75 |
-43:18:49.3 |
HIP 92973 |
2.84 |
| 2026-02-20 00:00 |
18:56:39.14 |
-43:18:53.4 |
HIP 92973 |
2.96 |
| 2026-02-20 12:00 |
18:56:40.51 |
-43:18:57.5 |
HIP 92973 |
3.09 |
| 2026-02-21 00:00 |
18:56:41.87 |
-43:19:01.8 |
HIP 92973 |
3.23 |
| 2026-02-21 12:00 |
18:56:43.21 |
-43:19:06.0 |
HIP 92973 |
3.39 |
| 2026-02-22 00:00 |
18:56:44.55 |
-43:19:10.4 |
HIP 92973 |
3.55 |
| 2026-02-22 12:00 |
18:56:45.87 |
-43:19:14.7 |
HIP 92973 |
3.72 |
| 2026-02-23 00:00 |
18:56:47.17 |
-43:19:19.2 |
HIP 92973 |
3.90 |
| 2026-02-23 12:00 |
18:56:48.46 |
-43:19:23.7 |
HIP 92973 |
4.08 |
| 2026-02-24 00:00 |
18:56:49.74 |
-43:19:28.2 |
HIP 92973 |
4.27 |