| Parameter |
Value |
| Designation |
C/2005 P3 (SWAN) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2005-08-09T17:53:55.314240Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:51Z |
| Obs used |
78 |
| NEO |
- |
| M1 |
13.000 |
| K1 |
9.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2005-09-05.0000000 |
| e |
0.98765964 |
| q (au) |
0.525760 |
| a (au) |
42.604934 |
| i (deg) |
89.706006 |
| Ω (om, deg) |
242.778577 |
| ω (w, deg) |
32.144830 |
| M (ma, deg) |
0.093049 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.682 + 2.791\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.682 |
| n |
2.791 |
| gf |
0.803 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
04:14:56.27 |
-00:44:04.5 |
HIP 19816 |
15.78 |
| 2026-03-26 12:00 |
04:14:57.78 |
-00:43:46.7 |
HIP 19816 |
16.07 |
| 2026-03-27 00:00 |
04:14:59.31 |
-00:43:28.9 |
HIP 19816 |
16.36 |
| 2026-03-27 12:00 |
04:15:00.86 |
-00:43:11.1 |
HIP 19816 |
16.67 |
| 2026-03-28 00:00 |
04:15:02.43 |
-00:42:53.4 |
HIP 19816 |
16.98 |
| 2026-03-28 12:00 |
04:15:04.03 |
-00:42:35.7 |
HIP 19816 |
17.30 |
| 2026-03-29 00:00 |
04:15:05.64 |
-00:42:18.0 |
HIP 19816 |
17.63 |
| 2026-03-29 12:00 |
04:15:07.28 |
-00:42:00.4 |
HIP 19816 |
17.96 |
| 2026-03-30 00:00 |
04:15:08.94 |
-00:41:42.8 |
HIP 19816 |
18.31 |
| 2026-03-30 12:00 |
04:15:10.62 |
-00:41:25.3 |
HIP 19816 |
18.66 |
| 2026-03-31 00:00 |
04:15:12.33 |
-00:41:07.7 |
HIP 19816 |
19.02 |
| 2026-03-31 12:00 |
04:15:14.05 |
-00:40:50.2 |
HIP 19816 |
19.38 |
| 2026-04-01 00:00 |
04:15:15.79 |
-00:40:32.8 |
HIP 19925 |
19.63 |
| 2026-04-01 12:00 |
04:15:17.56 |
-00:40:15.4 |
HIP 19925 |
19.12 |
| 2026-04-02 00:00 |
04:15:19.34 |
-00:39:58.0 |
HIP 19925 |
18.60 |
| 2026-04-02 12:00 |
04:15:21.15 |
-00:39:40.7 |
HIP 19925 |
18.09 |
| 2026-04-03 00:00 |
04:15:22.97 |
-00:39:23.4 |
HIP 19925 |
17.57 |
| 2026-04-03 12:00 |
04:15:24.82 |
-00:39:06.2 |
HIP 19925 |
17.04 |
| 2026-04-04 00:00 |
04:15:26.69 |
-00:38:49.0 |
HIP 19925 |
16.51 |
| 2026-04-04 12:00 |
04:15:28.57 |
-00:38:31.8 |
HIP 19925 |
15.98 |
| 2026-04-05 00:00 |
04:15:30.48 |
-00:38:14.7 |
HIP 19925 |
15.45 |
| 2026-04-05 12:00 |
04:15:32.40 |
-00:37:57.7 |
HIP 19925 |
14.91 |
| 2026-04-06 00:00 |
04:15:34.35 |
-00:37:40.7 |
HIP 19925 |
14.37 |
| 2026-04-06 12:00 |
04:15:36.31 |
-00:37:23.7 |
HIP 19925 |
13.83 |
| 2026-04-07 00:00 |
04:15:38.30 |
-00:37:06.9 |
HIP 19925 |
13.29 |
| 2026-04-07 12:00 |
04:15:40.30 |
-00:36:50.0 |
HIP 19925 |
12.74 |
| 2026-04-08 00:00 |
04:15:42.32 |
-00:36:33.2 |
HIP 19925 |
12.19 |
| 2026-04-08 12:00 |
04:15:44.36 |
-00:36:16.5 |
HIP 19925 |
11.64 |
| 2026-04-09 00:00 |
04:15:46.42 |
-00:35:59.8 |
HIP 19925 |
11.09 |
| 2026-04-09 12:00 |
04:15:48.50 |
-00:35:43.2 |
HIP 19925 |
10.53 |
| 2026-04-10 00:00 |
04:15:50.59 |
-00:35:26.7 |
HIP 19925 |
9.98 |
| 2026-04-10 12:00 |
04:15:52.71 |
-00:35:10.2 |
HIP 19925 |
9.43 |
| 2026-04-11 00:00 |
04:15:54.84 |
-00:34:53.8 |
HIP 19925 |
8.88 |
| 2026-04-11 12:00 |
04:15:56.99 |
-00:34:37.4 |
HIP 19925 |
8.33 |
| 2026-04-12 00:00 |
04:15:59.16 |
-00:34:21.1 |
HIP 19925 |
7.78 |
| 2026-04-12 12:00 |
04:16:01.34 |
-00:34:04.9 |
HIP 19925 |
7.24 |
| 2026-04-13 00:00 |
04:16:03.54 |
-00:33:48.7 |
HIP 19925 |
6.70 |
| 2026-04-13 12:00 |
04:16:05.76 |
-00:33:32.7 |
HIP 19925 |
6.18 |
| 2026-04-14 00:00 |
04:16:08.00 |
-00:33:16.6 |
HIP 19925 |
5.67 |
| 2026-04-14 12:00 |
04:16:10.26 |
-00:33:00.7 |
HIP 19925 |
5.18 |
| 2026-04-15 00:00 |
04:16:12.53 |
-00:32:44.8 |
HIP 19925 |
4.72 |
| 2026-04-15 12:00 |
04:16:14.81 |
-00:32:29.0 |
HIP 19925 |
4.29 |
| 2026-04-16 00:00 |
04:16:17.12 |
-00:32:13.3 |
HIP 19925 |
3.91 |