222P/LINEAR
| Parameter |
Value |
| Designation |
222P/LINEAR |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2009-09-01T04:04:48.025920Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:27:57Z |
| Obs used |
239 |
| NEO |
Yes |
| M1 |
19.300 |
| K1 |
11.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2008-06-03.0000000 |
| e |
0.72682414 |
| q (au) |
0.780587 |
| a (au) |
2.857451 |
| i (deg) |
5.146524 |
| Ω (om, deg) |
7.132797 |
| ω (w, deg) |
345.426748 |
| M (ma, deg) |
267.122715 |
Magnitude
Scatter + Global Linear
$$
M_a = (16.134 + 2.231\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
16.134 |
| n |
2.231 |
| gf |
1.000 |
| gb |
-0.748 |
| 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) |
| 2026-02-03 00:00 |
11:14:01.05 |
+08:01:41.2 |
HIP 54863 |
1.98 |
| 2026-02-03 12:00 |
11:13:43.22 |
+08:03:35.5 |
HIP 54863 |
4.60 |
| 2026-02-04 00:00 |
11:13:25.23 |
+08:05:30.7 |
HIP 54863 |
9.24 |
| 2026-02-04 12:00 |
11:13:07.06 |
+08:07:26.7 |
HIP 54863 |
14.07 |
| 2026-02-05 00:00 |
11:12:48.73 |
+08:09:23.4 |
HIP 54863 |
18.97 |
| 2026-02-05 12:00 |
11:12:30.23 |
+08:11:21.0 |
HIP 54863 |
23.94 |
| 2026-02-06 00:00 |
11:12:11.56 |
+08:13:19.3 |
HIP 54789 |
25.32 |
| 2026-02-06 12:00 |
11:11:52.74 |
+08:15:18.4 |
HIP 54789 |
26.28 |
| 2026-02-07 00:00 |
11:11:33.76 |
+08:17:18.2 |
HIP 54789 |
28.14 |
| 2026-02-07 12:00 |
11:11:14.62 |
+08:19:18.7 |
HIP 54604 |
28.00 |
| 2026-02-08 00:00 |
11:10:55.33 |
+08:21:19.9 |
HIP 54604 |
28.48 |
| 2026-02-08 12:00 |
11:10:35.89 |
+08:23:21.7 |
HIP 54604 |
29.89 |
| 2026-02-09 00:00 |
11:10:16.30 |
+08:25:24.2 |
HIP 54604 |
32.10 |
| 2026-02-09 12:00 |
11:09:56.56 |
+08:27:27.4 |
HIP 54604 |
34.99 |
| 2026-02-10 00:00 |
11:09:36.68 |
+08:29:31.1 |
HIP 54604 |
38.42 |
| 2026-02-10 12:00 |
11:09:16.66 |
+08:31:35.4 |
HIP 54417 |
34.54 |
| 2026-02-11 00:00 |
11:08:56.51 |
+08:33:40.3 |
HIP 54417 |
30.40 |
| 2026-02-11 12:00 |
11:08:36.22 |
+08:35:45.8 |
HIP 54417 |
26.71 |
| 2026-02-12 00:00 |
11:08:15.80 |
+08:37:51.7 |
HIP 54417 |
23.68 |
| 2026-02-12 12:00 |
11:07:55.25 |
+08:39:58.2 |
HIP 54417 |
21.62 |
| 2026-02-13 00:00 |
11:07:34.58 |
+08:42:05.1 |
HIP 54417 |
20.85 |
| 2026-02-13 12:00 |
11:07:13.79 |
+08:44:12.5 |
HIP 54417 |
21.54 |
| 2026-02-14 00:00 |
11:06:52.87 |
+08:46:20.3 |
HIP 54417 |
23.57 |
| 2026-02-14 12:00 |
11:06:31.85 |
+08:48:28.6 |
HIP 54417 |
26.66 |
| 2026-02-15 00:00 |
11:06:10.71 |
+08:50:37.2 |
HIP 54417 |
30.50 |
| 2026-02-15 12:00 |
11:05:49.46 |
+08:52:46.2 |
HIP 54417 |
34.86 |
| 2026-02-16 00:00 |
11:05:28.10 |
+08:54:55.5 |
HIP 54417 |
39.58 |
| 2026-02-16 12:00 |
11:05:06.65 |
+08:57:05.1 |
HIP 53977 |
40.22 |
| 2026-02-17 00:00 |
11:04:45.10 |
+08:59:15.1 |
HIP 53977 |
34.48 |
| 2026-02-17 12:00 |
11:04:23.45 |
+09:01:25.2 |
HIP 53977 |
28.73 |
| 2026-02-18 00:00 |
11:04:01.71 |
+09:03:35.7 |
HIP 53977 |
22.95 |
| 2026-02-18 12:00 |
11:03:39.88 |
+09:05:46.3 |
HIP 53977 |
17.17 |
| 2026-02-19 00:00 |
11:03:17.97 |
+09:07:57.2 |
HIP 53977 |
11.39 |
| 2026-02-19 12:00 |
11:02:55.97 |
+09:10:08.2 |
HIP 53977 |
5.70 |
| 2026-02-20 00:00 |
11:02:33.91 |
+09:12:19.3 |
HIP 53977 |
1.96 |
| 2026-02-20 12:00 |
11:02:11.76 |
+09:14:30.6 |
HIP 53977 |
6.65 |
| 2026-02-21 00:00 |
11:01:49.55 |
+09:16:41.9 |
HIP 53977 |
12.42 |
| 2026-02-21 12:00 |
11:01:27.28 |
+09:18:53.4 |
HIP 53977 |
18.29 |
| 2026-02-22 00:00 |
11:01:04.94 |
+09:21:04.8 |
HIP 53977 |
24.20 |
| 2026-02-22 12:00 |
11:00:42.54 |
+09:23:16.3 |
HIP 53977 |
30.12 |
| 2026-02-23 00:00 |
11:00:20.09 |
+09:25:27.8 |
HIP 53727 |
32.52 |
| 2026-02-23 12:00 |
10:59:57.59 |
+09:27:39.3 |
HIP 53727 |
28.83 |
| 2026-02-24 00:00 |
10:59:35.04 |
+09:29:50.7 |
HIP 53619 |
23.89 |