| 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) |
| 2026-06-01 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 |
| 2026-06-02 12:00 |
07:19:20.53 |
+34:32:35.9 |
HIP 35349 |
28.95 |
| 2026-06-03 00:00 |
07:19:21.61 |
+34:32:31.8 |
HIP 35349 |
29.13 |
| 2026-06-03 12:00 |
07:19:22.68 |
+34:32:27.8 |
HIP 35349 |
29.30 |
| 2026-06-04 00:00 |
07:19:23.77 |
+34:32:23.7 |
HIP 35349 |
29.48 |
| 2026-06-04 12:00 |
07:19:24.86 |
+34:32:19.7 |
HIP 35349 |
29.66 |
| 2026-06-05 00:00 |
07:19:25.95 |
+34:32:15.7 |
HIP 35349 |
29.84 |
| 2026-06-05 12:00 |
07:19:27.06 |
+34:32:11.7 |
HIP 35349 |
30.02 |
| 2026-06-06 00:00 |
07:19:28.17 |
+34:32:07.8 |
HIP 35349 |
30.20 |
| 2026-06-06 12:00 |
07:19:29.28 |
+34:32:03.8 |
HIP 35349 |
30.39 |
| 2026-06-07 00:00 |
07:19:30.41 |
+34:31:59.9 |
HIP 35349 |
30.57 |
| 2026-06-07 12:00 |
07:19:31.53 |
+34:31:55.9 |
HIP 35349 |
30.76 |
| 2026-06-08 00:00 |
07:19:32.67 |
+34:31:52.0 |
HIP 35349 |
30.95 |
| 2026-06-08 12:00 |
07:19:33.81 |
+34:31:48.1 |
HIP 35349 |
31.14 |
| 2026-06-09 00:00 |
07:19:34.95 |
+34:31:44.2 |
HIP 35349 |
31.33 |
| 2026-06-09 12:00 |
07:19:36.10 |
+34:31:40.4 |
HIP 35349 |
31.52 |
| 2026-06-10 00:00 |
07:19:37.26 |
+34:31:36.5 |
HIP 35349 |
31.71 |
| 2026-06-10 12:00 |
07:19:38.42 |
+34:31:32.7 |
HIP 35349 |
31.91 |
| 2026-06-11 00:00 |
07:19:39.59 |
+34:31:28.9 |
HIP 35349 |
32.10 |
| 2026-06-11 12:00 |
07:19:40.77 |
+34:31:25.1 |
HIP 35349 |
32.30 |
| 2026-06-12 00:00 |
07:19:41.95 |
+34:31:21.3 |
HIP 35349 |
32.49 |
| 2026-06-12 12:00 |
07:19:43.13 |
+34:31:17.5 |
HIP 35349 |
32.69 |
| 2026-06-13 00:00 |
07:19:44.32 |
+34:31:13.8 |
HIP 35349 |
32.89 |
| 2026-06-13 12:00 |
07:19:45.51 |
+34:31:10.0 |
HIP 35349 |
33.09 |
| 2026-06-14 00:00 |
07:19:46.71 |
+34:31:06.3 |
HIP 35349 |
33.29 |
| 2026-06-14 12:00 |
07:19:47.92 |
+34:31:02.6 |
HIP 35349 |
33.50 |
| 2026-06-15 00:00 |
07:19:49.13 |
+34:30:59.0 |
HIP 35349 |
33.70 |
| 2026-06-15 12:00 |
07:19:50.34 |
+34:30:55.3 |
HIP 35687 |
33.58 |
| 2026-06-16 00:00 |
07:19:51.56 |
+34:30:51.7 |
HIP 35687 |
33.45 |
| 2026-06-16 12:00 |
07:19:52.78 |
+34:30:48.1 |
HIP 35687 |
33.31 |
| 2026-06-17 00:00 |
07:19:54.01 |
+34:30:44.5 |
HIP 35687 |
33.17 |
| 2026-06-17 12:00 |
07:19:55.24 |
+34:30:40.9 |
HIP 35687 |
33.03 |
| 2026-06-18 00:00 |
07:19:56.48 |
+34:30:37.4 |
HIP 35687 |
32.90 |
| 2026-06-18 12:00 |
07:19:57.72 |
+34:30:33.8 |
HIP 35687 |
32.76 |
| 2026-06-19 00:00 |
07:19:58.96 |
+34:30:30.3 |
HIP 35687 |
32.63 |
| 2026-06-19 12:00 |
07:20:00.21 |
+34:30:26.8 |
HIP 35687 |
32.49 |
| 2026-06-20 00:00 |
07:20:01.46 |
+34:30:23.4 |
HIP 35687 |
32.36 |
| 2026-06-20 12:00 |
07:20:02.72 |
+34:30:19.9 |
HIP 35687 |
32.23 |
| 2026-06-21 00:00 |
07:20:03.98 |
+34:30:16.5 |
HIP 35687 |
32.10 |
| 2026-06-21 12:00 |
07:20:05.24 |
+34:30:13.1 |
HIP 35687 |
31.96 |
| 2026-06-22 00:00 |
07:20:06.51 |
+34:30:09.7 |
HIP 35687 |
31.84 |