322P/SOHO
| 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) |
| 2026-02-03 00:00 |
15:49:10.16 |
-29:40:52.9 |
HIP 77457 |
12.51 |
| 2026-02-03 12:00 |
15:49:19.91 |
-29:42:20.0 |
HIP 77457 |
14.63 |
| 2026-02-04 00:00 |
15:49:29.48 |
-29:43:46.8 |
HIP 77457 |
16.86 |
| 2026-02-04 12:00 |
15:49:38.86 |
-29:45:13.4 |
HIP 77457 |
19.14 |
| 2026-02-05 00:00 |
15:49:48.05 |
-29:46:39.8 |
HIP 77664 |
20.54 |
| 2026-02-05 12:00 |
15:49:57.05 |
-29:48:06.0 |
HIP 77664 |
19.14 |
| 2026-02-06 00:00 |
15:50:05.86 |
-29:49:31.9 |
HIP 77664 |
17.99 |
| 2026-02-06 12:00 |
15:50:14.47 |
-29:50:57.6 |
HIP 77664 |
17.14 |
| 2026-02-07 00:00 |
15:50:22.90 |
-29:52:23.0 |
HIP 77641 |
15.72 |
| 2026-02-07 12:00 |
15:50:31.12 |
-29:53:48.2 |
HIP 77641 |
13.55 |
| 2026-02-08 00:00 |
15:50:39.15 |
-29:55:13.1 |
HIP 77641 |
11.43 |
| 2026-02-08 12:00 |
15:50:46.98 |
-29:56:37.8 |
HIP 77641 |
9.40 |
| 2026-02-09 00:00 |
15:50:54.61 |
-29:58:02.2 |
HIP 77641 |
7.49 |
| 2026-02-09 12:00 |
15:51:02.04 |
-29:59:26.4 |
HIP 77641 |
5.77 |
| 2026-02-10 00:00 |
15:51:09.26 |
-30:00:50.3 |
HIP 77641 |
4.42 |
| 2026-02-10 12:00 |
15:51:16.27 |
-30:02:13.9 |
HIP 77641 |
3.79 |
| 2026-02-11 00:00 |
15:51:23.08 |
-30:03:37.3 |
HIP 77641 |
4.17 |
| 2026-02-11 12:00 |
15:51:29.67 |
-30:05:00.3 |
HIP 77641 |
5.30 |
| 2026-02-12 00:00 |
15:51:36.06 |
-30:06:23.1 |
HIP 77641 |
6.79 |
| 2026-02-12 12:00 |
15:51:42.23 |
-30:07:45.6 |
HIP 77641 |
8.42 |
| 2026-02-13 00:00 |
15:51:48.19 |
-30:09:07.8 |
HIP 77641 |
10.11 |
| 2026-02-13 12:00 |
15:51:53.93 |
-30:10:29.6 |
HIP 77641 |
11.81 |
| 2026-02-14 00:00 |
15:51:59.45 |
-30:11:51.2 |
HIP 77641 |
13.51 |
| 2026-02-14 12:00 |
15:52:04.76 |
-30:13:12.5 |
HIP 77641 |
15.18 |
| 2026-02-15 00:00 |
15:52:09.84 |
-30:14:33.4 |
HIP 77641 |
16.84 |
| 2026-02-15 12:00 |
15:52:14.69 |
-30:15:54.1 |
HIP 77641 |
18.46 |
| 2026-02-16 00:00 |
15:52:19.33 |
-30:17:14.4 |
HIP 77641 |
20.06 |
| 2026-02-16 12:00 |
15:52:23.73 |
-30:18:34.3 |
HIP 77641 |
21.63 |
| 2026-02-17 00:00 |
15:52:27.91 |
-30:19:54.0 |
HIP 77665 |
21.93 |
| 2026-02-17 12:00 |
15:52:31.86 |
-30:21:13.3 |
HIP 77665 |
21.58 |
| 2026-02-18 00:00 |
15:52:35.57 |
-30:22:32.2 |
HIP 77665 |
21.31 |
| 2026-02-18 12:00 |
15:52:39.06 |
-30:23:50.8 |
HIP 77665 |
21.10 |
| 2026-02-19 00:00 |
15:52:42.31 |
-30:25:09.0 |
HIP 77665 |
20.97 |
| 2026-02-19 12:00 |
15:52:45.32 |
-30:26:26.8 |
HIP 77665 |
20.89 |
| 2026-02-20 00:00 |
15:52:48.09 |
-30:27:44.3 |
HIP 77665 |
20.87 |
| 2026-02-20 12:00 |
15:52:50.63 |
-30:29:01.4 |
HIP 77665 |
20.90 |
| 2026-02-21 00:00 |
15:52:52.92 |
-30:30:18.1 |
HIP 77896 |
20.84 |
| 2026-02-21 12:00 |
15:52:54.97 |
-30:31:34.4 |
HIP 77683 |
20.57 |
| 2026-02-22 00:00 |
15:52:56.78 |
-30:32:50.3 |
HIP 77683 |
20.29 |
| 2026-02-22 12:00 |
15:52:58.35 |
-30:34:05.8 |
HIP 77683 |
20.04 |
| 2026-02-23 00:00 |
15:52:59.66 |
-30:35:20.9 |
HIP 77683 |
19.84 |
| 2026-02-23 12:00 |
15:53:00.73 |
-30:36:35.6 |
HIP 77683 |
19.66 |
| 2026-02-24 00:00 |
15:53:01.56 |
-30:37:49.9 |
HIP 77683 |
19.51 |