| 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 |
0.995 |
| gb |
-0.513 |
| k |
1.000 |
| δ90 |
9.998 |
| 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) |
| 2026-09-20 00:00 |
11:32:47.71 |
+04:10:48.4 |
HIP 56378 |
9.65 |
| 2026-09-20 12:00 |
11:33:10.04 |
+04:08:18.8 |
HIP 56378 |
3.69 |
| 2026-09-21 00:00 |
11:33:32.35 |
+04:05:49.2 |
HIP 56378 |
2.92 |
| 2026-09-21 12:00 |
11:33:54.66 |
+04:03:19.6 |
HIP 56378 |
8.82 |
| 2026-09-22 00:00 |
11:34:16.95 |
+04:00:50.2 |
HIP 56378 |
14.88 |
| 2026-09-22 12:00 |
11:34:39.24 |
+03:58:20.8 |
HIP 56569 |
17.57 |
| 2026-09-23 00:00 |
11:35:01.51 |
+03:55:51.5 |
HIP 56569 |
11.95 |
| 2026-09-23 12:00 |
11:35:23.77 |
+03:53:22.3 |
HIP 56569 |
7.15 |
| 2026-09-24 00:00 |
11:35:46.01 |
+03:50:53.2 |
HIP 56569 |
5.77 |
| 2026-09-24 12:00 |
11:36:08.24 |
+03:48:24.1 |
HIP 56569 |
9.45 |
| 2026-09-25 00:00 |
11:36:30.46 |
+03:45:55.2 |
HIP 56569 |
14.80 |
| 2026-09-25 12:00 |
11:36:52.66 |
+03:43:26.4 |
HIP 56747 |
19.08 |
| 2026-09-26 00:00 |
11:37:14.85 |
+03:40:57.6 |
HIP 56747 |
13.06 |
| 2026-09-26 12:00 |
11:37:37.02 |
+03:38:29.0 |
HIP 56747 |
7.10 |
| 2026-09-27 00:00 |
11:37:59.17 |
+03:36:00.5 |
HIP 56747 |
1.97 |
| 2026-09-27 12:00 |
11:38:21.31 |
+03:33:32.1 |
HIP 56747 |
5.54 |
| 2026-09-28 00:00 |
11:38:43.43 |
+03:31:03.8 |
HIP 56747 |
11.43 |
| 2026-09-28 12:00 |
11:39:05.53 |
+03:28:35.6 |
HIP 56747 |
17.42 |
| 2026-09-29 00:00 |
11:39:27.62 |
+03:26:07.5 |
HIP 56955 |
20.51 |
| 2026-09-29 12:00 |
11:39:49.68 |
+03:23:39.6 |
HIP 56955 |
18.67 |
| 2026-09-30 00:00 |
11:40:11.72 |
+03:21:11.8 |
HIP 56955 |
18.68 |
| 2026-09-30 12:00 |
11:40:33.75 |
+03:18:44.2 |
HIP 56955 |
20.54 |
| 2026-10-01 00:00 |
11:40:55.75 |
+03:16:16.6 |
HIP 56955 |
23.81 |
| 2026-10-01 12:00 |
11:41:17.73 |
+03:13:49.3 |
HIP 57084 |
24.71 |
| 2026-10-02 00:00 |
11:41:39.69 |
+03:11:22.0 |
HIP 57084 |
20.06 |
| 2026-10-02 12:00 |
11:42:01.63 |
+03:08:54.9 |
HIP 57084 |
16.32 |
| 2026-10-03 00:00 |
11:42:23.55 |
+03:06:28.0 |
HIP 57084 |
14.23 |
| 2026-10-03 12:00 |
11:42:45.44 |
+03:04:01.3 |
HIP 57084 |
14.50 |
| 2026-10-04 00:00 |
11:43:07.30 |
+03:01:34.7 |
HIP 57084 |
17.02 |
| 2026-10-04 12:00 |
11:43:29.14 |
+02:59:08.2 |
HIP 57084 |
20.99 |
| 2026-10-05 00:00 |
11:43:50.96 |
+02:56:42.0 |
HIP 57302 |
18.64 |
| 2026-10-05 12:00 |
11:44:12.75 |
+02:54:15.9 |
HIP 57302 |
15.32 |
| 2026-10-06 00:00 |
11:44:34.51 |
+02:51:50.0 |
HIP 57302 |
13.89 |
| 2026-10-06 12:00 |
11:44:56.25 |
+02:49:24.4 |
HIP 57370 |
11.53 |
| 2026-10-07 00:00 |
11:45:17.95 |
+02:46:58.9 |
HIP 57370 |
6.53 |
| 2026-10-07 12:00 |
11:45:39.63 |
+02:44:33.6 |
HIP 57370 |
4.80 |
| 2026-10-08 00:00 |
11:46:01.28 |
+02:42:08.5 |
HIP 57370 |
8.58 |
| 2026-10-08 12:00 |
11:46:22.89 |
+02:39:43.6 |
HIP 57370 |
13.93 |
| 2026-10-09 00:00 |
11:46:44.48 |
+02:37:19.0 |
HIP 57370 |
19.60 |
| 2026-10-09 12:00 |
11:47:06.03 |
+02:34:54.5 |
HIP 57370 |
25.36 |
| 2026-10-10 00:00 |
11:47:27.55 |
+02:32:30.3 |
HIP 57370 |
31.17 |
| 2026-10-10 12:00 |
11:47:49.03 |
+02:30:06.4 |
HIP 57525 |
29.88 |
| 2026-10-11 00:00 |
11:48:10.48 |
+02:27:42.6 |
HIP 57681 |
27.72 |