| Parameter |
Value |
| Designation |
C/2008 T2 (Cardinal) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2009-06-13T05:44:59.979840Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:24Z |
| Obs used |
1309 |
| NEO |
- |
| M1 |
11.200 |
| K1 |
5.250 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2009-02-08.0000000 |
| e |
1.00010902 |
| q (au) |
1.202208 |
| a (au) |
-11027.760878 |
| i (deg) |
56.303690 |
| Ω (om, deg) |
309.678521 |
| ω (w, deg) |
215.871148 |
| M (ma, deg) |
-0.000107 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.536 + 3.857\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.536 |
| n |
3.857 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.800 |
| 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 |
| 2008-03-20 |
2008-10-08 |
-32.2881 |
+17.516 |
| 2008-10-08 |
2009-04-10 |
+1.8402 |
-0.993 |
| 2009-04-10 |
2009-06-12 |
+22.8692 |
-5.412 |
| 2009-06-13 |
2009-10-10 |
+3.9717 |
-3.676 |
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 |
21:12:28.02 |
-03:08:07.6 |
HIP 104622 |
12.90 |
| 2026-06-01 12:00 |
21:12:26.75 |
-03:08:01.4 |
HIP 104622 |
12.58 |
| 2026-06-02 00:00 |
21:12:25.46 |
-03:07:55.4 |
HIP 104622 |
12.25 |
| 2026-06-02 12:00 |
21:12:24.15 |
-03:07:49.4 |
HIP 104622 |
11.92 |
| 2026-06-03 00:00 |
21:12:22.81 |
-03:07:43.7 |
HIP 104622 |
11.58 |
| 2026-06-03 12:00 |
21:12:21.45 |
-03:07:38.1 |
HIP 104622 |
11.24 |
| 2026-06-04 00:00 |
21:12:20.06 |
-03:07:32.6 |
HIP 104622 |
10.89 |
| 2026-06-04 12:00 |
21:12:18.65 |
-03:07:27.3 |
HIP 104622 |
10.53 |
| 2026-06-05 00:00 |
21:12:17.22 |
-03:07:22.1 |
HIP 104622 |
10.17 |
| 2026-06-05 12:00 |
21:12:15.76 |
-03:07:17.0 |
HIP 104622 |
9.81 |
| 2026-06-06 00:00 |
21:12:14.28 |
-03:07:12.2 |
HIP 104622 |
9.44 |
| 2026-06-06 12:00 |
21:12:12.78 |
-03:07:07.4 |
HIP 104622 |
9.06 |
| 2026-06-07 00:00 |
21:12:11.25 |
-03:07:02.8 |
HIP 104622 |
8.68 |
| 2026-06-07 12:00 |
21:12:09.69 |
-03:06:58.4 |
HIP 104622 |
8.30 |
| 2026-06-08 00:00 |
21:12:08.12 |
-03:06:54.1 |
HIP 104622 |
7.91 |
| 2026-06-08 12:00 |
21:12:06.52 |
-03:06:50.0 |
HIP 104622 |
7.51 |
| 2026-06-09 00:00 |
21:12:04.90 |
-03:06:46.0 |
HIP 104622 |
7.11 |
| 2026-06-09 12:00 |
21:12:03.25 |
-03:06:42.2 |
HIP 104622 |
6.71 |
| 2026-06-10 00:00 |
21:12:01.58 |
-03:06:38.5 |
HIP 104622 |
6.30 |
| 2026-06-10 12:00 |
21:11:59.89 |
-03:06:35.0 |
HIP 104622 |
5.88 |
| 2026-06-11 00:00 |
21:11:58.18 |
-03:06:31.6 |
HIP 104622 |
5.46 |
| 2026-06-11 12:00 |
21:11:56.44 |
-03:06:28.4 |
HIP 104622 |
5.04 |
| 2026-06-12 00:00 |
21:11:54.68 |
-03:06:25.3 |
HIP 104622 |
4.62 |
| 2026-06-12 12:00 |
21:11:52.90 |
-03:06:22.4 |
HIP 104622 |
4.19 |
| 2026-06-13 00:00 |
21:11:51.10 |
-03:06:19.6 |
HIP 104622 |
3.76 |
| 2026-06-13 12:00 |
21:11:49.27 |
-03:06:17.0 |
HIP 104622 |
3.33 |
| 2026-06-14 00:00 |
21:11:47.42 |
-03:06:14.5 |
HIP 104622 |
2.90 |
| 2026-06-14 12:00 |
21:11:45.55 |
-03:06:12.2 |
HIP 104622 |
2.48 |
| 2026-06-15 00:00 |
21:11:43.66 |
-03:06:10.0 |
HIP 104622 |
2.08 |
| 2026-06-15 12:00 |
21:11:41.75 |
-03:06:08.0 |
HIP 104622 |
1.70 |
| 2026-06-16 00:00 |
21:11:39.81 |
-03:06:06.2 |
HIP 104622 |
1.39 |
| 2026-06-16 12:00 |
21:11:37.86 |
-03:06:04.5 |
HIP 104622 |
1.19 |
| 2026-06-17 00:00 |
21:11:35.88 |
-03:06:02.9 |
HIP 104622 |
1.17 |
| 2026-06-17 12:00 |
21:11:33.88 |
-03:06:01.5 |
HIP 104622 |
1.35 |
| 2026-06-18 00:00 |
21:11:31.86 |
-03:06:00.3 |
HIP 104622 |
1.67 |
| 2026-06-18 12:00 |
21:11:29.82 |
-03:05:59.2 |
HIP 104622 |
2.06 |
| 2026-06-19 00:00 |
21:11:27.76 |
-03:05:58.3 |
HIP 104622 |
2.50 |
| 2026-06-19 12:00 |
21:11:25.68 |
-03:05:57.5 |
HIP 104622 |
2.97 |
| 2026-06-20 00:00 |
21:11:23.58 |
-03:05:56.9 |
HIP 104622 |
3.46 |
| 2026-06-20 12:00 |
21:11:21.46 |
-03:05:56.4 |
HIP 104622 |
3.96 |
| 2026-06-21 00:00 |
21:11:19.32 |
-03:05:56.1 |
HIP 104622 |
4.47 |
| 2026-06-21 12:00 |
21:11:17.16 |
-03:05:55.9 |
HIP 104622 |
4.99 |
| 2026-06-22 00:00 |
21:11:14.98 |
-03:05:55.9 |
HIP 104622 |
5.52 |