| Parameter |
Value |
| Designation |
322P/SOHO |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2015-09-04T01:32:14.300160Z |
| Orbit solution date (soln_date, UTC) |
2016-10-27T11:29:40Z |
| Obs used |
318 |
| NEO |
Yes |
| M1 |
19.000 |
| K1 |
10.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2015-06-06.0000000 |
| e |
0.97867648 |
| q (au) |
0.053656 |
| a (au) |
2.516261 |
| i (deg) |
12.589236 |
| Ω (om, deg) |
359.524488 |
| ω (w, deg) |
49.049477 |
| M (ma, deg) |
337.760659 |
Magnitude
Scatter + Global Linear
$$
M_a = (20.000 + 4.648\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
20.000 |
| n |
4.648 |
| gf |
0.800 |
| gb |
-1.000 |
| k |
0.800 |
| δ90 |
1.000 |
| 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 |
15:45:28.89 |
-31:33:30.3 |
HIP 77059 |
18.26 |
| 2026-03-26 12:00 |
15:45:12.40 |
-31:34:00.1 |
HIP 77059 |
14.71 |
| 2026-03-27 00:00 |
15:44:55.62 |
-31:34:28.9 |
HIP 77059 |
11.10 |
| 2026-03-27 12:00 |
15:44:38.53 |
-31:34:56.5 |
HIP 77059 |
7.44 |
| 2026-03-28 00:00 |
15:44:21.15 |
-31:35:23.0 |
HIP 77059 |
3.72 |
| 2026-03-28 12:00 |
15:44:03.47 |
-31:35:48.3 |
HIP 77059 |
0.41 |
| 2026-03-29 00:00 |
15:43:45.49 |
-31:36:12.4 |
HIP 77059 |
3.96 |
| 2026-03-29 12:00 |
15:43:27.22 |
-31:36:35.4 |
HIP 77059 |
7.86 |
| 2026-03-30 00:00 |
15:43:08.65 |
-31:36:57.1 |
HIP 77059 |
11.83 |
| 2026-03-30 12:00 |
15:42:49.79 |
-31:37:17.6 |
HIP 77059 |
15.86 |
| 2026-03-31 00:00 |
15:42:30.63 |
-31:37:36.9 |
HIP 76840 |
14.98 |
| 2026-03-31 12:00 |
15:42:11.18 |
-31:37:54.9 |
HIP 76840 |
10.83 |
| 2026-04-01 00:00 |
15:41:51.44 |
-31:38:11.6 |
HIP 76840 |
6.64 |
| 2026-04-01 12:00 |
15:41:31.40 |
-31:38:27.1 |
HIP 76840 |
2.45 |
| 2026-04-02 00:00 |
15:41:11.08 |
-31:38:41.2 |
HIP 76840 |
2.18 |
| 2026-04-02 12:00 |
15:40:50.46 |
-31:38:54.1 |
HIP 76840 |
6.46 |
| 2026-04-03 00:00 |
15:40:29.56 |
-31:39:05.6 |
HIP 76840 |
10.90 |
| 2026-04-03 12:00 |
15:40:08.37 |
-31:39:15.8 |
HIP 76840 |
15.40 |
| 2026-04-04 00:00 |
15:39:46.89 |
-31:39:24.6 |
HIP 76840 |
19.97 |
| 2026-04-04 12:00 |
15:39:25.13 |
-31:39:32.1 |
HIP 76840 |
24.61 |
| 2026-04-05 00:00 |
15:39:03.08 |
-31:39:38.1 |
HIP 76499 |
21.94 |
| 2026-04-05 12:00 |
15:38:40.75 |
-31:39:42.8 |
HIP 76499 |
17.64 |
| 2026-04-06 00:00 |
15:38:18.13 |
-31:39:46.0 |
HIP 76499 |
13.58 |
| 2026-04-06 12:00 |
15:37:55.24 |
-31:39:47.8 |
HIP 76499 |
10.14 |
| 2026-04-07 00:00 |
15:37:32.07 |
-31:39:48.1 |
HIP 76499 |
8.26 |
| 2026-04-07 12:00 |
15:37:08.62 |
-31:39:47.0 |
HIP 76499 |
9.09 |
| 2026-04-08 00:00 |
15:36:44.90 |
-31:39:44.4 |
HIP 76499 |
12.14 |
| 2026-04-08 12:00 |
15:36:20.90 |
-31:39:40.3 |
HIP 76499 |
16.26 |
| 2026-04-09 00:00 |
15:35:56.63 |
-31:39:34.7 |
HIP 76326 |
15.02 |
| 2026-04-09 12:00 |
15:35:32.10 |
-31:39:27.5 |
HIP 76326 |
13.88 |
| 2026-04-10 00:00 |
15:35:07.29 |
-31:39:18.9 |
HIP 76326 |
14.68 |
| 2026-04-10 12:00 |
15:34:42.22 |
-31:39:08.6 |
HIP 76326 |
17.20 |
| 2026-04-11 00:00 |
15:34:16.88 |
-31:38:56.8 |
HIP 76326 |
20.87 |
| 2026-04-11 12:00 |
15:33:51.28 |
-31:38:43.4 |
HIP 76190 |
23.29 |
| 2026-04-12 00:00 |
15:33:25.43 |
-31:38:28.5 |
HIP 76190 |
23.76 |
| 2026-04-12 12:00 |
15:32:59.31 |
-31:38:11.9 |
HIP 76190 |
25.47 |
| 2026-04-13 00:00 |
15:32:32.95 |
-31:37:53.7 |
HIP 76190 |
28.25 |
| 2026-04-13 12:00 |
15:32:06.33 |
-31:37:33.8 |
HIP 76084 |
29.15 |
| 2026-04-14 00:00 |
15:31:39.46 |
-31:37:12.3 |
HIP 76084 |
29.93 |
| 2026-04-14 12:00 |
15:31:12.34 |
-31:36:49.2 |
HIP 76084 |
31.75 |
| 2026-04-15 00:00 |
15:30:44.98 |
-31:36:24.3 |
HIP 75772 |
26.53 |
| 2026-04-15 12:00 |
15:30:17.39 |
-31:35:57.8 |
HIP 75772 |
20.83 |
| 2026-04-16 00:00 |
15:29:49.55 |
-31:35:29.6 |
HIP 75772 |
15.21 |