| 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) |
| 2026-07-29 00:00 |
10:54:27.64 |
+08:27:10.3 |
HIP 53430 |
21.17 |
| 2026-07-29 12:00 |
10:54:47.59 |
+08:24:56.9 |
HIP 53430 |
17.65 |
| 2026-07-30 00:00 |
10:55:07.59 |
+08:22:43.2 |
HIP 53430 |
15.28 |
| 2026-07-30 12:00 |
10:55:27.65 |
+08:20:29.1 |
HIP 53430 |
14.63 |
| 2026-07-31 00:00 |
10:55:47.77 |
+08:18:14.6 |
HIP 53430 |
15.95 |
| 2026-07-31 12:00 |
10:56:07.93 |
+08:15:59.8 |
HIP 53430 |
18.82 |
| 2026-08-01 00:00 |
10:56:28.15 |
+08:13:44.7 |
HIP 53597 |
22.12 |
| 2026-08-01 12:00 |
10:56:48.42 |
+08:11:29.2 |
HIP 53597 |
16.82 |
| 2026-08-02 00:00 |
10:57:08.75 |
+08:09:13.4 |
HIP 53597 |
11.68 |
| 2026-08-02 12:00 |
10:57:29.12 |
+08:06:57.3 |
HIP 53597 |
7.12 |
| 2026-08-03 00:00 |
10:57:49.54 |
+08:04:40.9 |
HIP 53597 |
5.11 |
| 2026-08-03 12:00 |
10:58:10.02 |
+08:02:24.1 |
HIP 53597 |
7.95 |
| 2026-08-04 00:00 |
10:58:30.54 |
+08:00:07.0 |
HIP 53597 |
12.74 |
| 2026-08-04 12:00 |
10:58:51.11 |
+07:57:49.6 |
HIP 53597 |
17.99 |
| 2026-08-05 00:00 |
10:59:11.73 |
+07:55:31.9 |
HIP 53597 |
23.42 |
| 2026-08-05 12:00 |
10:59:32.39 |
+07:53:13.9 |
HIP 53848 |
26.37 |
| 2026-08-06 00:00 |
10:59:53.11 |
+07:50:55.5 |
HIP 53848 |
20.95 |
| 2026-08-06 12:00 |
11:00:13.87 |
+07:48:36.9 |
HIP 53848 |
15.65 |
| 2026-08-07 00:00 |
11:00:34.67 |
+07:46:18.0 |
HIP 53848 |
10.70 |
| 2026-08-07 12:00 |
11:00:55.52 |
+07:43:58.7 |
HIP 53848 |
6.92 |
| 2026-08-08 00:00 |
11:01:16.41 |
+07:41:39.2 |
HIP 53848 |
6.74 |
| 2026-08-08 12:00 |
11:01:37.35 |
+07:39:19.4 |
HIP 53848 |
10.37 |
| 2026-08-09 00:00 |
11:01:58.33 |
+07:36:59.3 |
HIP 53848 |
15.32 |
| 2026-08-09 12:00 |
11:02:19.35 |
+07:34:38.9 |
HIP 54057 |
20.31 |
| 2026-08-10 00:00 |
11:02:40.41 |
+07:32:18.2 |
HIP 54057 |
15.32 |
| 2026-08-10 12:00 |
11:03:01.52 |
+07:29:57.3 |
HIP 54057 |
11.04 |
| 2026-08-11 00:00 |
11:03:22.66 |
+07:27:36.1 |
HIP 54057 |
8.66 |
| 2026-08-11 12:00 |
11:03:43.84 |
+07:25:14.6 |
HIP 54057 |
9.70 |
| 2026-08-12 00:00 |
11:04:05.07 |
+07:22:52.9 |
HIP 54057 |
13.40 |
| 2026-08-12 12:00 |
11:04:26.33 |
+07:20:30.9 |
HIP 54182 |
8.66 |
| 2026-08-13 00:00 |
11:04:47.63 |
+07:18:08.7 |
HIP 54182 |
3.93 |
| 2026-08-13 12:00 |
11:05:08.96 |
+07:15:46.2 |
HIP 54182 |
4.80 |
| 2026-08-14 00:00 |
11:05:30.33 |
+07:13:23.5 |
HIP 54182 |
9.90 |
| 2026-08-14 12:00 |
11:05:51.74 |
+07:11:00.5 |
HIP 54274 |
5.12 |
| 2026-08-15 00:00 |
11:06:13.18 |
+07:08:37.4 |
HIP 54274 |
0.96 |
| 2026-08-15 12:00 |
11:06:34.65 |
+07:06:13.9 |
HIP 54274 |
6.61 |
| 2026-08-16 00:00 |
11:06:56.16 |
+07:03:50.3 |
HIP 54268 |
12.23 |
| 2026-08-16 12:00 |
11:07:17.70 |
+07:01:26.4 |
HIP 54268 |
17.45 |
| 2026-08-17 00:00 |
11:07:39.27 |
+06:59:02.4 |
HIP 54331 |
20.80 |
| 2026-08-17 12:00 |
11:08:00.87 |
+06:56:38.1 |
HIP 54423 |
22.44 |
| 2026-08-18 00:00 |
11:08:22.50 |
+06:54:13.6 |
HIP 54423 |
19.94 |
| 2026-08-18 12:00 |
11:08:44.16 |
+06:51:48.9 |
HIP 54423 |
18.99 |
| 2026-08-19 00:00 |
11:09:05.85 |
+06:49:24.0 |
HIP 54423 |
19.83 |