C/2003 A2 (Gleason)
| Parameter |
Value |
| Designation |
C/2003 A2 (Gleason) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2003-11-05T00:23:36.450240Z |
| Orbit solution date (soln_date, UTC) |
2025-07-31T12:12:22Z |
| Obs used |
165 |
| NEO |
- |
| M1 |
6.500 |
| K1 |
7.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2003-08-08.0000000 |
| e |
1.00694108 |
| q (au) |
11.427006 |
| a (au) |
-1646.285863 |
| i (deg) |
8.061536 |
| Ω (om, deg) |
154.544669 |
| ω (w, deg) |
346.638010 |
| M (ma, deg) |
-0.001313 |
Magnitude
Scatter + Global Linear
$$
M_a = (-2.179 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
-2.179 |
| n |
6.000 |
| gf |
0.898 |
| gb |
-0.974 |
| k |
1.000 |
| δ90 |
4.460 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
16:56:48.52 |
-14:43:36.0 |
HIP 83029 |
18.72 |
| 2026-02-03 12:00 |
16:56:50.70 |
-14:43:33.8 |
HIP 83029 |
18.23 |
| 2026-02-04 00:00 |
16:56:52.86 |
-14:43:31.6 |
HIP 83029 |
17.76 |
| 2026-02-04 12:00 |
16:56:54.99 |
-14:43:29.4 |
HIP 83029 |
17.29 |
| 2026-02-05 00:00 |
16:56:57.09 |
-14:43:27.0 |
HIP 83029 |
16.84 |
| 2026-02-05 12:00 |
16:56:59.18 |
-14:43:24.6 |
HIP 83029 |
16.39 |
| 2026-02-06 00:00 |
16:57:01.23 |
-14:43:22.1 |
HIP 83029 |
15.95 |
| 2026-02-06 12:00 |
16:57:03.27 |
-14:43:19.5 |
HIP 83029 |
15.52 |
| 2026-02-07 00:00 |
16:57:05.27 |
-14:43:16.9 |
HIP 83029 |
15.10 |
| 2026-02-07 12:00 |
16:57:07.26 |
-14:43:14.2 |
HIP 83029 |
14.69 |
| 2026-02-08 00:00 |
16:57:09.22 |
-14:43:11.5 |
HIP 83029 |
14.30 |
| 2026-02-08 12:00 |
16:57:11.15 |
-14:43:08.6 |
HIP 83029 |
13.91 |
| 2026-02-09 00:00 |
16:57:13.05 |
-14:43:05.7 |
HIP 83029 |
13.53 |
| 2026-02-09 12:00 |
16:57:14.94 |
-14:43:02.7 |
HIP 83029 |
13.17 |
| 2026-02-10 00:00 |
16:57:16.79 |
-14:42:59.7 |
HIP 83029 |
12.81 |
| 2026-02-10 12:00 |
16:57:18.62 |
-14:42:56.6 |
HIP 83029 |
12.47 |
| 2026-02-11 00:00 |
16:57:20.42 |
-14:42:53.4 |
HIP 83029 |
12.14 |
| 2026-02-11 12:00 |
16:57:22.20 |
-14:42:50.2 |
HIP 83029 |
11.83 |
| 2026-02-12 00:00 |
16:57:23.95 |
-14:42:46.9 |
HIP 83029 |
11.52 |
| 2026-02-12 12:00 |
16:57:25.68 |
-14:42:43.5 |
HIP 83029 |
11.23 |
| 2026-02-13 00:00 |
16:57:27.38 |
-14:42:40.0 |
HIP 83029 |
10.96 |
| 2026-02-13 12:00 |
16:57:29.05 |
-14:42:36.5 |
HIP 83029 |
10.70 |
| 2026-02-14 00:00 |
16:57:30.69 |
-14:42:32.9 |
HIP 83029 |
10.45 |
| 2026-02-14 12:00 |
16:57:32.31 |
-14:42:29.3 |
HIP 83029 |
10.22 |
| 2026-02-15 00:00 |
16:57:33.91 |
-14:42:25.6 |
HIP 83029 |
10.01 |
| 2026-02-15 12:00 |
16:57:35.47 |
-14:42:21.8 |
HIP 83029 |
9.81 |
| 2026-02-16 00:00 |
16:57:37.01 |
-14:42:18.0 |
HIP 83029 |
9.63 |
| 2026-02-16 12:00 |
16:57:38.52 |
-14:42:14.1 |
HIP 83029 |
9.46 |
| 2026-02-17 00:00 |
16:57:40.00 |
-14:42:10.1 |
HIP 83029 |
9.31 |
| 2026-02-17 12:00 |
16:57:41.46 |
-14:42:06.1 |
HIP 83029 |
9.17 |
| 2026-02-18 00:00 |
16:57:42.88 |
-14:42:02.0 |
HIP 83029 |
9.06 |
| 2026-02-18 12:00 |
16:57:44.29 |
-14:41:57.8 |
HIP 83029 |
8.96 |
| 2026-02-19 00:00 |
16:57:45.66 |
-14:41:53.6 |
HIP 83029 |
8.87 |
| 2026-02-19 12:00 |
16:57:47.00 |
-14:41:49.4 |
HIP 83029 |
8.80 |
| 2026-02-20 00:00 |
16:57:48.32 |
-14:41:45.0 |
HIP 83029 |
8.75 |
| 2026-02-20 12:00 |
16:57:49.61 |
-14:41:40.6 |
HIP 83029 |
8.71 |
| 2026-02-21 00:00 |
16:57:50.87 |
-14:41:36.2 |
HIP 83029 |
8.68 |
| 2026-02-21 12:00 |
16:57:52.10 |
-14:41:31.6 |
HIP 83029 |
8.67 |
| 2026-02-22 00:00 |
16:57:53.31 |
-14:41:27.1 |
HIP 83029 |
8.68 |
| 2026-02-22 12:00 |
16:57:54.49 |
-14:41:22.4 |
HIP 83029 |
8.69 |
| 2026-02-23 00:00 |
16:57:55.64 |
-14:41:17.7 |
HIP 83029 |
8.72 |
| 2026-02-23 12:00 |
16:57:56.76 |
-14:41:13.0 |
HIP 83029 |
8.76 |
| 2026-02-24 00:00 |
16:57:57.85 |
-14:41:08.2 |
HIP 83029 |
8.81 |