| Parameter |
Value |
| Designation |
C/1947 S1 (Bester) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1948-02-16T10:08:20.811840Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:07Z |
| Obs used |
42 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1948-01-07.0000000 |
| e |
1.00034321 |
| q (au) |
0.748130 |
| a (au) |
-2179.799629 |
| i (deg) |
140.568676 |
| Ω (om, deg) |
271.438753 |
| ω (w, deg) |
350.213543 |
| M (ma, deg) |
-0.000391 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.180 + 3.781\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.180 |
| n |
3.781 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
0.952 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 1947-10-05 |
1948-01-12 |
+0.4348 |
-0.045 |
| 1948-02-28 |
1948-05-08 |
-2.2957 |
+0.187 |
| 1948-05-08 |
1949-02-06 |
+6.1259 |
-2.020 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
07:18:41.79 |
+34:35:39.4 |
HIP 35349 |
22.71 |
| 2026-05-12 12:00 |
07:18:42.51 |
+34:35:35.1 |
HIP 35349 |
22.82 |
| 2026-05-13 00:00 |
07:18:43.23 |
+34:35:30.7 |
HIP 35349 |
22.94 |
| 2026-05-13 12:00 |
07:18:43.97 |
+34:35:26.3 |
HIP 35349 |
23.06 |
| 2026-05-14 00:00 |
07:18:44.72 |
+34:35:21.9 |
HIP 35349 |
23.19 |
| 2026-05-14 12:00 |
07:18:45.47 |
+34:35:17.5 |
HIP 35349 |
23.31 |
| 2026-05-15 00:00 |
07:18:46.24 |
+34:35:13.2 |
HIP 35349 |
23.43 |
| 2026-05-15 12:00 |
07:18:47.01 |
+34:35:08.8 |
HIP 35349 |
23.56 |
| 2026-05-16 00:00 |
07:18:47.79 |
+34:35:04.4 |
HIP 35349 |
23.68 |
| 2026-05-16 12:00 |
07:18:48.59 |
+34:35:00.1 |
HIP 35349 |
23.81 |
| 2026-05-17 00:00 |
07:18:49.39 |
+34:34:55.7 |
HIP 35349 |
23.94 |
| 2026-05-17 12:00 |
07:18:50.20 |
+34:34:51.3 |
HIP 35349 |
24.07 |
| 2026-05-18 00:00 |
07:18:51.02 |
+34:34:47.0 |
HIP 35349 |
24.20 |
| 2026-05-18 12:00 |
07:18:51.85 |
+34:34:42.6 |
HIP 35349 |
24.34 |
| 2026-05-19 00:00 |
07:18:52.69 |
+34:34:38.3 |
HIP 35349 |
24.47 |
| 2026-05-19 12:00 |
07:18:53.54 |
+34:34:34.0 |
HIP 35349 |
24.61 |
| 2026-05-20 00:00 |
07:18:54.39 |
+34:34:29.6 |
HIP 35349 |
24.74 |
| 2026-05-20 12:00 |
07:18:55.26 |
+34:34:25.3 |
HIP 35349 |
24.88 |
| 2026-05-21 00:00 |
07:18:56.13 |
+34:34:21.0 |
HIP 35349 |
25.02 |
| 2026-05-21 12:00 |
07:18:57.01 |
+34:34:16.7 |
HIP 35349 |
25.16 |
| 2026-05-22 00:00 |
07:18:57.90 |
+34:34:12.4 |
HIP 35349 |
25.30 |
| 2026-05-22 12:00 |
07:18:58.80 |
+34:34:08.1 |
HIP 35349 |
25.45 |
| 2026-05-23 00:00 |
07:18:59.71 |
+34:34:03.8 |
HIP 35349 |
25.59 |
| 2026-05-23 12:00 |
07:19:00.62 |
+34:33:59.5 |
HIP 35349 |
25.74 |
| 2026-05-24 00:00 |
07:19:01.54 |
+34:33:55.2 |
HIP 35349 |
25.89 |
| 2026-05-24 12:00 |
07:19:02.47 |
+34:33:51.0 |
HIP 35349 |
26.04 |
| 2026-05-25 00:00 |
07:19:03.41 |
+34:33:46.7 |
HIP 35349 |
26.19 |
| 2026-05-25 12:00 |
07:19:04.36 |
+34:33:42.4 |
HIP 35349 |
26.34 |
| 2026-05-26 00:00 |
07:19:05.32 |
+34:33:38.2 |
HIP 35349 |
26.49 |
| 2026-05-26 12:00 |
07:19:06.28 |
+34:33:34.0 |
HIP 35349 |
26.65 |
| 2026-05-27 00:00 |
07:19:07.25 |
+34:33:29.8 |
HIP 35349 |
26.80 |
| 2026-05-27 12:00 |
07:19:08.23 |
+34:33:25.5 |
HIP 35349 |
26.96 |
| 2026-05-28 00:00 |
07:19:09.21 |
+34:33:21.3 |
HIP 35349 |
27.12 |
| 2026-05-28 12:00 |
07:19:10.21 |
+34:33:17.2 |
HIP 35349 |
27.28 |
| 2026-05-29 00:00 |
07:19:11.21 |
+34:33:13.0 |
HIP 35349 |
27.44 |
| 2026-05-29 12:00 |
07:19:12.21 |
+34:33:08.8 |
HIP 35349 |
27.60 |
| 2026-05-30 00:00 |
07:19:13.23 |
+34:33:04.6 |
HIP 35349 |
27.77 |
| 2026-05-30 12:00 |
07:19:14.25 |
+34:33:00.5 |
HIP 35349 |
27.93 |
| 2026-05-31 00:00 |
07:19:15.28 |
+34:32:56.4 |
HIP 35349 |
28.10 |
| 2026-05-31 12:00 |
07:19:16.32 |
+34:32:52.2 |
HIP 35349 |
28.27 |
| 2026-06-01 00:00 |
07:19:17.36 |
+34:32:48.1 |
HIP 35349 |
28.44 |
| 2026-06-01 12:00 |
07:19:18.41 |
+34:32:44.0 |
HIP 35349 |
28.61 |
| 2026-06-02 00:00 |
07:19:19.47 |
+34:32:40.0 |
HIP 35349 |
28.78 |