| Parameter |
Value |
| Designation |
C/2012 E2 (SWAN) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2012-03-15T00:41:51.241920Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:04Z |
| Obs used |
43 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2012-03-13.0000000 |
| e |
1.00049131 |
| q (au) |
0.006962 |
| a (au) |
-14.169573 |
| i (deg) |
144.430741 |
| Ω (om, deg) |
6.576461 |
| ω (w, deg) |
82.412294 |
| M (ma, deg) |
-0.037494 |
Magnitude
Scatter + Global Linear
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| 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) |
| 2026-06-01 00:00 |
06:59:04.27 |
-11:45:01.1 |
HIP 33569 |
20.99 |
| 2026-06-01 12:00 |
06:59:06.71 |
-11:44:50.8 |
HIP 33693 |
20.80 |
| 2026-06-02 00:00 |
06:59:09.15 |
-11:44:40.6 |
HIP 33693 |
20.54 |
| 2026-06-02 12:00 |
06:59:11.61 |
-11:44:30.6 |
HIP 33693 |
20.28 |
| 2026-06-03 00:00 |
06:59:14.08 |
-11:44:20.9 |
HIP 33693 |
20.04 |
| 2026-06-03 12:00 |
06:59:16.57 |
-11:44:11.3 |
HIP 33693 |
19.81 |
| 2026-06-04 00:00 |
06:59:19.06 |
-11:44:01.9 |
HIP 33693 |
19.59 |
| 2026-06-04 12:00 |
06:59:21.57 |
-11:43:52.7 |
HIP 33693 |
19.39 |
| 2026-06-05 00:00 |
06:59:24.09 |
-11:43:43.7 |
HIP 33693 |
19.20 |
| 2026-06-05 12:00 |
06:59:26.62 |
-11:43:34.9 |
HIP 33693 |
19.03 |
| 2026-06-06 00:00 |
06:59:29.16 |
-11:43:26.3 |
HIP 33693 |
18.87 |
| 2026-06-06 12:00 |
06:59:31.71 |
-11:43:17.9 |
HIP 33693 |
18.73 |
| 2026-06-07 00:00 |
06:59:34.27 |
-11:43:09.7 |
HIP 33693 |
18.60 |
| 2026-06-07 12:00 |
06:59:36.85 |
-11:43:01.7 |
HIP 33693 |
18.49 |
| 2026-06-08 00:00 |
06:59:39.43 |
-11:42:53.9 |
HIP 33693 |
18.40 |
| 2026-06-08 12:00 |
06:59:42.02 |
-11:42:46.2 |
HIP 33693 |
18.33 |
| 2026-06-09 00:00 |
06:59:44.63 |
-11:42:38.8 |
HIP 33693 |
18.28 |
| 2026-06-09 12:00 |
06:59:47.24 |
-11:42:31.6 |
HIP 33693 |
18.25 |
| 2026-06-10 00:00 |
06:59:49.87 |
-11:42:24.6 |
HIP 33693 |
18.23 |
| 2026-06-10 12:00 |
06:59:52.50 |
-11:42:17.8 |
HIP 33693 |
18.24 |
| 2026-06-11 00:00 |
06:59:55.15 |
-11:42:11.1 |
HIP 33693 |
18.27 |
| 2026-06-11 12:00 |
06:59:57.80 |
-11:42:04.7 |
HIP 33693 |
18.31 |
| 2026-06-12 00:00 |
07:00:00.46 |
-11:41:58.5 |
HIP 33693 |
18.38 |
| 2026-06-12 12:00 |
07:00:03.13 |
-11:41:52.5 |
HIP 33693 |
18.46 |
| 2026-06-13 00:00 |
07:00:05.81 |
-11:41:46.7 |
HIP 33693 |
18.57 |
| 2026-06-13 12:00 |
07:00:08.50 |
-11:41:41.1 |
HIP 33693 |
18.70 |
| 2026-06-14 00:00 |
07:00:11.20 |
-11:41:35.7 |
HIP 33693 |
18.84 |
| 2026-06-14 12:00 |
07:00:13.90 |
-11:41:30.4 |
HIP 33693 |
19.00 |
| 2026-06-15 00:00 |
07:00:16.61 |
-11:41:25.4 |
HIP 33693 |
19.19 |
| 2026-06-15 12:00 |
07:00:19.34 |
-11:41:20.7 |
HIP 33693 |
19.39 |
| 2026-06-16 00:00 |
07:00:22.06 |
-11:41:16.1 |
HIP 33693 |
19.61 |
| 2026-06-16 12:00 |
07:00:24.80 |
-11:41:11.7 |
HIP 33693 |
19.84 |
| 2026-06-17 00:00 |
07:00:27.54 |
-11:41:07.5 |
HIP 33693 |
20.10 |
| 2026-06-17 12:00 |
07:00:30.29 |
-11:41:03.5 |
HIP 33693 |
20.37 |
| 2026-06-18 00:00 |
07:00:33.05 |
-11:40:59.7 |
HIP 33693 |
20.65 |
| 2026-06-18 12:00 |
07:00:35.81 |
-11:40:56.2 |
HIP 33693 |
20.96 |
| 2026-06-19 00:00 |
07:00:38.58 |
-11:40:52.8 |
HIP 33693 |
21.27 |
| 2026-06-19 12:00 |
07:00:41.36 |
-11:40:49.7 |
HIP 33693 |
21.60 |
| 2026-06-20 00:00 |
07:00:44.14 |
-11:40:46.7 |
HIP 33693 |
21.95 |
| 2026-06-20 12:00 |
07:00:46.93 |
-11:40:44.0 |
HIP 33693 |
22.31 |
| 2026-06-21 00:00 |
07:00:49.72 |
-11:40:41.4 |
HIP 33693 |
22.68 |
| 2026-06-21 12:00 |
07:00:52.52 |
-11:40:39.1 |
HIP 33693 |
23.06 |
| 2026-06-22 00:00 |
07:00:55.32 |
-11:40:37.0 |
HIP 33693 |
23.45 |