| Parameter |
Value |
| Designation |
C/2004 X2 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2004-08-24T08:00:06.079680Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:45Z |
| Obs used |
252 |
| NEO |
- |
| M1 |
12.900 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2005-01-15.0000000 |
| e |
0.99737720 |
| q (au) |
3.793087 |
| a (au) |
1446.194953 |
| i (deg) |
72.117890 |
| Ω (om, deg) |
307.341187 |
| ω (w, deg) |
162.215319 |
| M (ma, deg) |
0.002575 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.808 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.808 |
| n |
2.000 |
| gf |
0.998 |
| gb |
-0.783 |
| k |
0.800 |
| 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) |
| 2026-05-12 00:00 |
20:24:01.59 |
-71:43:28.1 |
HIP 100679 |
5.15 |
| 2026-05-12 12:00 |
20:23:58.97 |
-71:44:00.5 |
HIP 100679 |
5.70 |
| 2026-05-13 00:00 |
20:23:56.28 |
-71:44:32.8 |
HIP 100679 |
6.25 |
| 2026-05-13 12:00 |
20:23:53.50 |
-71:45:05.0 |
HIP 100679 |
6.82 |
| 2026-05-14 00:00 |
20:23:50.65 |
-71:45:37.2 |
HIP 100679 |
7.38 |
| 2026-05-14 12:00 |
20:23:47.72 |
-71:46:09.4 |
HIP 100679 |
7.95 |
| 2026-05-15 00:00 |
20:23:44.71 |
-71:46:41.5 |
HIP 100679 |
8.53 |
| 2026-05-15 12:00 |
20:23:41.63 |
-71:47:13.6 |
HIP 100679 |
9.11 |
| 2026-05-16 00:00 |
20:23:38.47 |
-71:47:45.6 |
HIP 100679 |
9.69 |
| 2026-05-16 12:00 |
20:23:35.23 |
-71:48:17.6 |
HIP 100679 |
10.28 |
| 2026-05-17 00:00 |
20:23:31.92 |
-71:48:49.5 |
HIP 100679 |
10.87 |
| 2026-05-17 12:00 |
20:23:28.53 |
-71:49:21.3 |
HIP 100679 |
11.46 |
| 2026-05-18 00:00 |
20:23:25.06 |
-71:49:53.1 |
HIP 100679 |
12.05 |
| 2026-05-18 12:00 |
20:23:21.52 |
-71:50:24.8 |
HIP 100679 |
12.65 |
| 2026-05-19 00:00 |
20:23:17.90 |
-71:50:56.4 |
HIP 100679 |
13.24 |
| 2026-05-19 12:00 |
20:23:14.21 |
-71:51:28.0 |
HIP 100679 |
13.84 |
| 2026-05-20 00:00 |
20:23:10.44 |
-71:51:59.5 |
HIP 100679 |
14.44 |
| 2026-05-20 12:00 |
20:23:06.59 |
-71:52:30.9 |
HIP 100679 |
15.05 |
| 2026-05-21 00:00 |
20:23:02.67 |
-71:53:02.2 |
HIP 100679 |
15.65 |
| 2026-05-21 12:00 |
20:22:58.68 |
-71:53:33.4 |
HIP 100679 |
16.26 |
| 2026-05-22 00:00 |
20:22:54.61 |
-71:54:04.5 |
HIP 100679 |
16.86 |
| 2026-05-22 12:00 |
20:22:50.47 |
-71:54:35.6 |
HIP 100679 |
17.47 |
| 2026-05-23 00:00 |
20:22:46.26 |
-71:55:06.5 |
HIP 100679 |
18.08 |
| 2026-05-23 12:00 |
20:22:41.97 |
-71:55:37.4 |
HIP 100679 |
18.69 |
| 2026-05-24 00:00 |
20:22:37.61 |
-71:56:08.1 |
HIP 100457 |
18.25 |
| 2026-05-24 12:00 |
20:22:33.17 |
-71:56:38.7 |
HIP 100457 |
17.71 |
| 2026-05-25 00:00 |
20:22:28.67 |
-71:57:09.3 |
HIP 100457 |
17.18 |
| 2026-05-25 12:00 |
20:22:24.09 |
-71:57:39.7 |
HIP 100457 |
16.66 |
| 2026-05-26 00:00 |
20:22:19.44 |
-71:58:10.0 |
HIP 100457 |
16.14 |
| 2026-05-26 12:00 |
20:22:14.71 |
-71:58:40.2 |
HIP 100457 |
15.64 |
| 2026-05-27 00:00 |
20:22:09.92 |
-71:59:10.3 |
HIP 100457 |
15.15 |
| 2026-05-27 12:00 |
20:22:05.06 |
-71:59:40.3 |
HIP 100457 |
14.66 |
| 2026-05-28 00:00 |
20:22:00.12 |
-72:00:10.1 |
HIP 100457 |
14.20 |
| 2026-05-28 12:00 |
20:21:55.11 |
-72:00:39.8 |
HIP 100457 |
13.74 |
| 2026-05-29 00:00 |
20:21:50.04 |
-72:01:09.4 |
HIP 100457 |
13.31 |
| 2026-05-29 12:00 |
20:21:44.89 |
-72:01:38.9 |
HIP 100457 |
12.89 |
| 2026-05-30 00:00 |
20:21:39.68 |
-72:02:08.2 |
HIP 100457 |
12.49 |
| 2026-05-30 12:00 |
20:21:34.39 |
-72:02:37.4 |
HIP 100457 |
12.12 |
| 2026-05-31 00:00 |
20:21:29.04 |
-72:03:06.5 |
HIP 100457 |
11.77 |
| 2026-05-31 12:00 |
20:21:23.62 |
-72:03:35.4 |
HIP 100457 |
11.45 |
| 2026-06-01 00:00 |
20:21:18.13 |
-72:04:04.2 |
HIP 100457 |
11.17 |
| 2026-06-01 12:00 |
20:21:12.57 |
-72:04:32.8 |
HIP 100457 |
10.92 |
| 2026-06-02 00:00 |
20:21:06.94 |
-72:05:01.3 |
HIP 100457 |
10.70 |