| Parameter |
Value |
| Designation |
C/2010 B1 (Cardinal) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2011-02-07T01:26:00.456000Z |
| Orbit solution date (soln_date, UTC) |
2025-06-26T10:12:44Z |
| Obs used |
2090 |
| NEO |
- |
| M1 |
9.600 |
| K1 |
7.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2010-10-26.0000000 |
| e |
0.99899435 |
| q (au) |
2.941487 |
| a (au) |
2924.960222 |
| i (deg) |
101.977683 |
| Ω (om, deg) |
277.213907 |
| ω (w, deg) |
211.519913 |
| M (ma, deg) |
359.999352 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.297 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.297 |
| n |
2.000 |
| gf |
0.999 |
| gb |
-0.709 |
| 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 |
| 2010-01-19 |
2010-08-30 |
+4.8225 |
-3.111 |
| 2010-08-30 |
2011-02-06 |
-10.8522 |
+5.203 |
| 2011-02-07 |
2012-02-12 |
+3.6110 |
-1.630 |
| 2012-02-12 |
2014-03-13 |
-14.7522 |
+11.129 |
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 |
18:41:59.59 |
-26:49:11.3 |
HIP 91621 |
12.79 |
| 2026-05-12 12:00 |
18:41:56.73 |
-26:49:12.6 |
HIP 91621 |
12.21 |
| 2026-05-13 00:00 |
18:41:53.85 |
-26:49:13.9 |
HIP 91621 |
11.63 |
| 2026-05-13 12:00 |
18:41:50.94 |
-26:49:15.1 |
HIP 91621 |
11.05 |
| 2026-05-14 00:00 |
18:41:48.00 |
-26:49:16.4 |
HIP 91621 |
10.47 |
| 2026-05-14 12:00 |
18:41:45.04 |
-26:49:17.7 |
HIP 91621 |
9.90 |
| 2026-05-15 00:00 |
18:41:42.04 |
-26:49:19.0 |
HIP 91621 |
9.34 |
| 2026-05-15 12:00 |
18:41:39.02 |
-26:49:20.3 |
HIP 91621 |
8.78 |
| 2026-05-16 00:00 |
18:41:35.98 |
-26:49:21.6 |
HIP 91621 |
8.24 |
| 2026-05-16 12:00 |
18:41:32.91 |
-26:49:22.9 |
HIP 91621 |
7.71 |
| 2026-05-17 00:00 |
18:41:29.81 |
-26:49:24.1 |
HIP 91621 |
7.21 |
| 2026-05-17 12:00 |
18:41:26.69 |
-26:49:25.4 |
HIP 91621 |
6.74 |
| 2026-05-18 00:00 |
18:41:23.54 |
-26:49:26.7 |
HIP 91621 |
6.30 |
| 2026-05-18 12:00 |
18:41:20.37 |
-26:49:28.0 |
HIP 91621 |
5.92 |
| 2026-05-19 00:00 |
18:41:17.17 |
-26:49:29.2 |
HIP 91621 |
5.59 |
| 2026-05-19 12:00 |
18:41:13.94 |
-26:49:30.5 |
HIP 91621 |
5.34 |
| 2026-05-20 00:00 |
18:41:10.70 |
-26:49:31.8 |
HIP 91621 |
5.18 |
| 2026-05-20 12:00 |
18:41:07.43 |
-26:49:33.0 |
HIP 91621 |
5.12 |
| 2026-05-21 00:00 |
18:41:04.13 |
-26:49:34.3 |
HIP 91621 |
5.16 |
| 2026-05-21 12:00 |
18:41:00.81 |
-26:49:35.5 |
HIP 91621 |
5.30 |
| 2026-05-22 00:00 |
18:40:57.47 |
-26:49:36.7 |
HIP 91621 |
5.54 |
| 2026-05-22 12:00 |
18:40:54.10 |
-26:49:38.0 |
HIP 91621 |
5.87 |
| 2026-05-23 00:00 |
18:40:50.72 |
-26:49:39.2 |
HIP 91621 |
6.28 |
| 2026-05-23 12:00 |
18:40:47.31 |
-26:49:40.4 |
HIP 91621 |
6.75 |
| 2026-05-24 00:00 |
18:40:43.87 |
-26:49:41.6 |
HIP 91621 |
7.27 |
| 2026-05-24 12:00 |
18:40:40.42 |
-26:49:42.8 |
HIP 91621 |
7.84 |
| 2026-05-25 00:00 |
18:40:36.94 |
-26:49:43.9 |
HIP 91621 |
8.44 |
| 2026-05-25 12:00 |
18:40:33.45 |
-26:49:45.1 |
HIP 91621 |
9.07 |
| 2026-05-26 00:00 |
18:40:29.93 |
-26:49:46.3 |
HIP 91621 |
9.73 |
| 2026-05-26 12:00 |
18:40:26.39 |
-26:49:47.4 |
HIP 91621 |
10.41 |
| 2026-05-27 00:00 |
18:40:22.83 |
-26:49:48.5 |
HIP 91621 |
11.11 |
| 2026-05-27 12:00 |
18:40:19.25 |
-26:49:49.7 |
HIP 91621 |
11.82 |
| 2026-05-28 00:00 |
18:40:15.65 |
-26:49:50.8 |
HIP 91621 |
12.55 |
| 2026-05-28 12:00 |
18:40:12.03 |
-26:49:51.9 |
HIP 91621 |
13.29 |
| 2026-05-29 00:00 |
18:40:08.39 |
-26:49:52.9 |
HIP 91621 |
14.04 |
| 2026-05-29 12:00 |
18:40:04.73 |
-26:49:54.0 |
HIP 91621 |
14.80 |
| 2026-05-30 00:00 |
18:40:01.05 |
-26:49:55.0 |
HIP 91621 |
15.58 |
| 2026-05-30 12:00 |
18:39:57.36 |
-26:49:56.1 |
HIP 91621 |
16.36 |
| 2026-05-31 00:00 |
18:39:53.64 |
-26:49:57.1 |
HIP 91621 |
17.14 |
| 2026-05-31 12:00 |
18:39:49.91 |
-26:49:58.1 |
HIP 91621 |
17.94 |
| 2026-06-01 00:00 |
18:39:46.16 |
-26:49:59.1 |
HIP 91621 |
18.74 |
| 2026-06-01 12:00 |
18:39:42.39 |
-26:50:00.0 |
HIP 91621 |
19.55 |
| 2026-06-02 00:00 |
18:39:38.60 |
-26:50:01.0 |
HIP 91621 |
20.37 |