| Parameter |
Value |
| Designation |
C/1947 F1 (Rondanina-Bester) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1947-05-20T23:09:22.504320Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:07Z |
| Obs used |
15 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1947-04-18.0000000 |
| e |
0.99727691 |
| q (au) |
0.559812 |
| a (au) |
205.579925 |
| i (deg) |
39.291590 |
| Ω (om, deg) |
353.903996 |
| ω (w, deg) |
303.758245 |
| M (ma, deg) |
359.988977 |
Magnitude
Scatter + Global Linear
$$
M_a = (7.611 + 3.727\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
7.611 |
| n |
3.727 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
0.950 |
| δ90 |
1.000 |
| 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 |
08:36:09.52 |
+54:10:29.7 |
HIP 42167 |
27.15 |
| 2026-07-29 12:00 |
08:36:11.49 |
+54:10:25.9 |
HIP 42167 |
27.13 |
| 2026-07-30 00:00 |
08:36:13.46 |
+54:10:22.2 |
HIP 42167 |
27.10 |
| 2026-07-30 12:00 |
08:36:15.44 |
+54:10:18.5 |
HIP 42167 |
27.09 |
| 2026-07-31 00:00 |
08:36:17.41 |
+54:10:15.0 |
HIP 42167 |
27.08 |
| 2026-07-31 12:00 |
08:36:19.38 |
+54:10:11.5 |
HIP 42167 |
27.07 |
| 2026-08-01 00:00 |
08:36:21.34 |
+54:10:08.1 |
HIP 42167 |
27.07 |
| 2026-08-01 12:00 |
08:36:23.31 |
+54:10:04.9 |
HIP 42167 |
27.07 |
| 2026-08-02 00:00 |
08:36:25.28 |
+54:10:01.6 |
HIP 42167 |
27.08 |
| 2026-08-02 12:00 |
08:36:27.25 |
+54:09:58.5 |
HIP 42167 |
27.09 |
| 2026-08-03 00:00 |
08:36:29.22 |
+54:09:55.5 |
HIP 42167 |
27.11 |
| 2026-08-03 12:00 |
08:36:31.18 |
+54:09:52.5 |
HIP 42167 |
27.13 |
| 2026-08-04 00:00 |
08:36:33.15 |
+54:09:49.7 |
HIP 42167 |
27.15 |
| 2026-08-04 12:00 |
08:36:35.11 |
+54:09:46.9 |
HIP 42167 |
27.18 |
| 2026-08-05 00:00 |
08:36:37.07 |
+54:09:44.2 |
HIP 42167 |
27.22 |
| 2026-08-05 12:00 |
08:36:39.03 |
+54:09:41.6 |
HIP 42167 |
27.26 |
| 2026-08-06 00:00 |
08:36:40.99 |
+54:09:39.1 |
HIP 42167 |
27.30 |
| 2026-08-06 12:00 |
08:36:42.95 |
+54:09:36.7 |
HIP 42167 |
27.35 |
| 2026-08-07 00:00 |
08:36:44.90 |
+54:09:34.4 |
HIP 42167 |
27.40 |
| 2026-08-07 12:00 |
08:36:46.86 |
+54:09:32.1 |
HIP 42167 |
27.45 |
| 2026-08-08 00:00 |
08:36:48.81 |
+54:09:30.0 |
HIP 42167 |
27.51 |
| 2026-08-08 12:00 |
08:36:50.76 |
+54:09:27.9 |
HIP 42167 |
27.58 |
| 2026-08-09 00:00 |
08:36:52.70 |
+54:09:25.9 |
HIP 42167 |
27.65 |
| 2026-08-09 12:00 |
08:36:54.65 |
+54:09:24.0 |
HIP 42167 |
27.72 |
| 2026-08-10 00:00 |
08:36:56.59 |
+54:09:22.2 |
HIP 42167 |
27.80 |
| 2026-08-10 12:00 |
08:36:58.52 |
+54:09:20.5 |
HIP 42167 |
27.88 |
| 2026-08-11 00:00 |
08:37:00.46 |
+54:09:18.9 |
HIP 42167 |
27.96 |
| 2026-08-11 12:00 |
08:37:02.39 |
+54:09:17.4 |
HIP 42167 |
28.05 |
| 2026-08-12 00:00 |
08:37:04.32 |
+54:09:15.9 |
HIP 42167 |
28.14 |
| 2026-08-12 12:00 |
08:37:06.24 |
+54:09:14.6 |
HIP 42167 |
28.24 |
| 2026-08-13 00:00 |
08:37:08.16 |
+54:09:13.3 |
HIP 42167 |
28.34 |
| 2026-08-13 12:00 |
08:37:10.08 |
+54:09:12.2 |
HIP 42167 |
28.44 |
| 2026-08-14 00:00 |
08:37:12.00 |
+54:09:11.1 |
HIP 42167 |
28.55 |
| 2026-08-14 12:00 |
08:37:13.91 |
+54:09:10.1 |
HIP 42167 |
28.66 |
| 2026-08-15 00:00 |
08:37:15.81 |
+54:09:09.2 |
HIP 42393 |
28.62 |
| 2026-08-15 12:00 |
08:37:17.71 |
+54:09:08.4 |
HIP 42393 |
28.49 |
| 2026-08-16 00:00 |
08:37:19.61 |
+54:09:07.7 |
HIP 42393 |
28.36 |
| 2026-08-16 12:00 |
08:37:21.50 |
+54:09:07.1 |
HIP 42393 |
28.23 |
| 2026-08-17 00:00 |
08:37:23.39 |
+54:09:06.6 |
HIP 42393 |
28.11 |
| 2026-08-17 12:00 |
08:37:25.27 |
+54:09:06.2 |
HIP 42393 |
27.99 |
| 2026-08-18 00:00 |
08:37:27.15 |
+54:09:05.8 |
HIP 42393 |
27.88 |
| 2026-08-18 12:00 |
08:37:29.02 |
+54:09:05.6 |
HIP 42393 |
27.77 |
| 2026-08-19 00:00 |
08:37:30.89 |
+54:09:05.4 |
HIP 42393 |
27.67 |