| Parameter |
Value |
| Designation |
C/1954 O2 (Baade) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1955-08-13T07:51:21.994560Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:12Z |
| Obs used |
35 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1955-09-19.0000000 |
| e |
1.00055852 |
| q (au) |
3.869944 |
| a (au) |
-6928.925768 |
| i (deg) |
100.387736 |
| Ω (om, deg) |
265.340699 |
| ω (w, deg) |
144.674890 |
| M (ma, deg) |
0.000063 |
Magnitude
Scatter + Global Linear
$$
M_a = (-0.462 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
-0.462 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| k |
1.000 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 1955-09-09 |
1957-11-02 |
+4.8428 |
-3.023 |
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 |
20:39:08.85 |
-79:33:42.5 |
HIP 102608 |
28.64 |
| 2026-06-01 12:00 |
20:39:05.03 |
-79:33:57.5 |
HIP 102608 |
28.62 |
| 2026-06-02 00:00 |
20:39:01.16 |
-79:34:12.3 |
HIP 102608 |
28.61 |
| 2026-06-02 12:00 |
20:38:57.25 |
-79:34:27.1 |
HIP 102608 |
28.60 |
| 2026-06-03 00:00 |
20:38:53.28 |
-79:34:41.9 |
HIP 102608 |
28.60 |
| 2026-06-03 12:00 |
20:38:49.26 |
-79:34:56.5 |
HIP 102608 |
28.60 |
| 2026-06-04 00:00 |
20:38:45.19 |
-79:35:11.1 |
HIP 102608 |
28.61 |
| 2026-06-04 12:00 |
20:38:41.08 |
-79:35:25.7 |
HIP 102608 |
28.62 |
| 2026-06-05 00:00 |
20:38:36.91 |
-79:35:40.1 |
HIP 102608 |
28.64 |
| 2026-06-05 12:00 |
20:38:32.69 |
-79:35:54.5 |
HIP 102608 |
28.67 |
| 2026-06-06 00:00 |
20:38:28.42 |
-79:36:08.8 |
HIP 102608 |
28.70 |
| 2026-06-06 12:00 |
20:38:24.11 |
-79:36:23.1 |
HIP 102608 |
28.74 |
| 2026-06-07 00:00 |
20:38:19.74 |
-79:36:37.2 |
HIP 102608 |
28.78 |
| 2026-06-07 12:00 |
20:38:15.33 |
-79:36:51.3 |
HIP 102608 |
28.83 |
| 2026-06-08 00:00 |
20:38:10.87 |
-79:37:05.4 |
HIP 102608 |
28.88 |
| 2026-06-08 12:00 |
20:38:06.36 |
-79:37:19.3 |
HIP 102608 |
28.94 |
| 2026-06-09 00:00 |
20:38:01.81 |
-79:37:33.1 |
HIP 102608 |
29.00 |
| 2026-06-09 12:00 |
20:37:57.20 |
-79:37:46.9 |
HIP 102608 |
29.07 |
| 2026-06-10 00:00 |
20:37:52.55 |
-79:38:00.6 |
HIP 102608 |
29.15 |
| 2026-06-10 12:00 |
20:37:47.85 |
-79:38:14.2 |
HIP 102608 |
29.23 |
| 2026-06-11 00:00 |
20:37:43.11 |
-79:38:27.8 |
HIP 102608 |
29.32 |
| 2026-06-11 12:00 |
20:37:38.32 |
-79:38:41.2 |
HIP 102608 |
29.41 |
| 2026-06-12 00:00 |
20:37:33.48 |
-79:38:54.6 |
HIP 102608 |
29.51 |
| 2026-06-12 12:00 |
20:37:28.60 |
-79:39:07.8 |
HIP 102608 |
29.61 |
| 2026-06-13 00:00 |
20:37:23.67 |
-79:39:21.0 |
HIP 102608 |
29.71 |
| 2026-06-13 12:00 |
20:37:18.70 |
-79:39:34.1 |
HIP 102608 |
29.83 |
| 2026-06-14 00:00 |
20:37:13.68 |
-79:39:47.1 |
HIP 102608 |
29.94 |
| 2026-06-14 12:00 |
20:37:08.62 |
-79:40:00.0 |
HIP 102608 |
30.07 |
| 2026-06-15 00:00 |
20:37:03.51 |
-79:40:12.9 |
HIP 102608 |
30.20 |
| 2026-06-15 12:00 |
20:36:58.36 |
-79:40:25.6 |
HIP 102608 |
30.33 |
| 2026-06-16 00:00 |
20:36:53.17 |
-79:40:38.2 |
HIP 100913 |
30.46 |
| 2026-06-16 12:00 |
20:36:47.94 |
-79:40:50.7 |
HIP 100913 |
30.38 |
| 2026-06-17 00:00 |
20:36:42.66 |
-79:41:03.2 |
HIP 100913 |
30.30 |
| 2026-06-17 12:00 |
20:36:37.34 |
-79:41:15.5 |
HIP 100913 |
30.22 |
| 2026-06-18 00:00 |
20:36:31.98 |
-79:41:27.7 |
HIP 100913 |
30.14 |
| 2026-06-18 12:00 |
20:36:26.58 |
-79:41:39.8 |
HIP 100913 |
30.06 |
| 2026-06-19 00:00 |
20:36:21.13 |
-79:41:51.9 |
HIP 100913 |
29.98 |
| 2026-06-19 12:00 |
20:36:15.65 |
-79:42:03.8 |
HIP 100913 |
29.90 |
| 2026-06-20 00:00 |
20:36:10.13 |
-79:42:15.6 |
HIP 100913 |
29.82 |
| 2026-06-20 12:00 |
20:36:04.57 |
-79:42:27.3 |
HIP 100913 |
29.75 |
| 2026-06-21 00:00 |
20:35:58.97 |
-79:42:38.9 |
HIP 100913 |
29.67 |
| 2026-06-21 12:00 |
20:35:53.33 |
-79:42:50.4 |
HIP 100913 |
29.60 |
| 2026-06-22 00:00 |
20:35:47.65 |
-79:43:01.8 |
HIP 100913 |
29.53 |