| Parameter |
Value |
| Designation |
C/2002 U2 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2002-12-31T23:39:13.196160Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:22Z |
| Obs used |
372 |
| NEO |
- |
| M1 |
14.300 |
| K1 |
12.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2003-01-02.0000000 |
| e |
1.00004468 |
| q (au) |
1.208632 |
| a (au) |
-27048.498281 |
| i (deg) |
59.135691 |
| Ω (om, deg) |
38.776625 |
| ω (w, deg) |
95.846952 |
| M (ma, deg) |
0.000000 |
Magnitude
Scatter + Global Linear
$$
M_a = (13.157 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.157 |
| n |
6.000 |
| gf |
0.984 |
| gb |
-0.818 |
| k |
0.997 |
| δ90 |
9.691 |
| 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 |
20:30:35.58 |
-78:56:04.3 |
HIP 101137 |
2.34 |
| 2026-09-20 12:00 |
20:30:28.05 |
-78:55:40.0 |
HIP 101137 |
1.79 |
| 2026-09-21 00:00 |
20:30:20.63 |
-78:55:15.4 |
HIP 101137 |
1.25 |
| 2026-09-21 12:00 |
20:30:13.30 |
-78:54:50.7 |
HIP 101137 |
0.71 |
| 2026-09-22 00:00 |
20:30:06.08 |
-78:54:25.7 |
HIP 101137 |
0.20 |
| 2026-09-22 12:00 |
20:29:58.96 |
-78:54:00.5 |
HIP 101137 |
0.40 |
| 2026-09-23 00:00 |
20:29:51.94 |
-78:53:35.1 |
HIP 101137 |
0.93 |
| 2026-09-23 12:00 |
20:29:45.03 |
-78:53:09.5 |
HIP 101137 |
1.47 |
| 2026-09-24 00:00 |
20:29:38.21 |
-78:52:43.7 |
HIP 101137 |
2.01 |
| 2026-09-24 12:00 |
20:29:31.50 |
-78:52:17.7 |
HIP 101137 |
2.55 |
| 2026-09-25 00:00 |
20:29:24.90 |
-78:51:51.5 |
HIP 101137 |
3.09 |
| 2026-09-25 12:00 |
20:29:18.40 |
-78:51:25.1 |
HIP 101137 |
3.63 |
| 2026-09-26 00:00 |
20:29:12.00 |
-78:50:58.5 |
HIP 101137 |
4.17 |
| 2026-09-26 12:00 |
20:29:05.71 |
-78:50:31.8 |
HIP 101137 |
4.71 |
| 2026-09-27 00:00 |
20:28:59.52 |
-78:50:04.8 |
HIP 101137 |
5.25 |
| 2026-09-27 12:00 |
20:28:53.44 |
-78:49:37.6 |
HIP 101137 |
5.79 |
| 2026-09-28 00:00 |
20:28:47.47 |
-78:49:10.3 |
HIP 100891 |
5.52 |
| 2026-09-28 12:00 |
20:28:41.60 |
-78:48:42.8 |
HIP 100891 |
5.00 |
| 2026-09-29 00:00 |
20:28:35.84 |
-78:48:15.1 |
HIP 100891 |
4.49 |
| 2026-09-29 12:00 |
20:28:30.18 |
-78:47:47.2 |
HIP 100891 |
3.98 |
| 2026-09-30 00:00 |
20:28:24.63 |
-78:47:19.2 |
HIP 100891 |
3.49 |
| 2026-09-30 12:00 |
20:28:19.19 |
-78:46:51.0 |
HIP 100891 |
3.02 |
| 2026-10-01 00:00 |
20:28:13.86 |
-78:46:22.6 |
HIP 100891 |
2.57 |
| 2026-10-01 12:00 |
20:28:08.63 |
-78:45:54.1 |
HIP 100891 |
2.17 |
| 2026-10-02 00:00 |
20:28:03.51 |
-78:45:25.3 |
HIP 100891 |
1.85 |
| 2026-10-02 12:00 |
20:27:58.51 |
-78:44:56.5 |
HIP 100891 |
1.66 |
| 2026-10-03 00:00 |
20:27:53.61 |
-78:44:27.4 |
HIP 100891 |
1.63 |
| 2026-10-03 12:00 |
20:27:48.82 |
-78:43:58.2 |
HIP 100891 |
1.78 |
| 2026-10-04 00:00 |
20:27:44.14 |
-78:43:28.9 |
HIP 100891 |
2.07 |
| 2026-10-04 12:00 |
20:27:39.57 |
-78:42:59.3 |
HIP 100891 |
2.45 |
| 2026-10-05 00:00 |
20:27:35.10 |
-78:42:29.7 |
HIP 100891 |
2.89 |
| 2026-10-05 12:00 |
20:27:30.75 |
-78:41:59.9 |
HIP 100891 |
3.35 |
| 2026-10-06 00:00 |
20:27:26.51 |
-78:41:29.9 |
HIP 100891 |
3.84 |
| 2026-10-06 12:00 |
20:27:22.38 |
-78:40:59.8 |
HIP 100891 |
4.35 |
| 2026-10-07 00:00 |
20:27:18.37 |
-78:40:29.5 |
HIP 100891 |
4.86 |
| 2026-10-07 12:00 |
20:27:14.46 |
-78:39:59.2 |
HIP 100891 |
5.38 |
| 2026-10-08 00:00 |
20:27:10.66 |
-78:39:28.6 |
HIP 100891 |
5.91 |
| 2026-10-08 12:00 |
20:27:06.98 |
-78:38:58.0 |
HIP 100891 |
6.44 |
| 2026-10-09 00:00 |
20:27:03.41 |
-78:38:27.2 |
HIP 100891 |
6.97 |
| 2026-10-09 12:00 |
20:26:59.95 |
-78:37:56.3 |
HIP 100891 |
7.51 |
| 2026-10-10 00:00 |
20:26:56.60 |
-78:37:25.2 |
HIP 100891 |
8.05 |
| 2026-10-10 12:00 |
20:26:53.36 |
-78:36:54.1 |
HIP 100891 |
8.59 |
| 2026-10-11 00:00 |
20:26:50.24 |
-78:36:22.8 |
HIP 100891 |
9.13 |