| Parameter |
Value |
| Designation |
C/2002 X1 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2003-07-12T21:19:27.825600Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:24Z |
| Obs used |
1432 |
| NEO |
- |
| M1 |
12.400 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2003-04-21.0000000 |
| e |
0.99818758 |
| q (au) |
2.486699 |
| a (au) |
1372.033208 |
| i (deg) |
164.089428 |
| Ω (om, deg) |
281.887134 |
| ω (w, deg) |
207.325128 |
| M (ma, deg) |
359.998392 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.579 + 2.717\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.579 |
| n |
2.717 |
| gf |
1.000 |
| gb |
-0.681 |
| k |
0.995 |
| δ90 |
9.999 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2002-02-21 |
2003-05-02 |
-0.1664 |
-0.115 |
| 2003-08-03 |
2004-01-17 |
+21.3196 |
-9.226 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
18:57:57.22 |
-22:52:07.8 |
HIP 93155 |
14.61 |
| 2026-05-12 12:00 |
18:57:55.24 |
-22:52:10.0 |
HIP 93155 |
14.89 |
| 2026-05-13 00:00 |
18:57:53.23 |
-22:52:12.2 |
HIP 93155 |
15.18 |
| 2026-05-13 12:00 |
18:57:51.21 |
-22:52:14.5 |
HIP 93155 |
15.48 |
| 2026-05-14 00:00 |
18:57:49.16 |
-22:52:16.8 |
HIP 93155 |
15.80 |
| 2026-05-14 12:00 |
18:57:47.10 |
-22:52:19.1 |
HIP 93155 |
16.12 |
| 2026-05-15 00:00 |
18:57:45.01 |
-22:52:21.4 |
HIP 93155 |
16.45 |
| 2026-05-15 12:00 |
18:57:42.90 |
-22:52:23.7 |
HIP 93155 |
16.80 |
| 2026-05-16 00:00 |
18:57:40.78 |
-22:52:26.1 |
HIP 93155 |
17.16 |
| 2026-05-16 12:00 |
18:57:38.63 |
-22:52:28.5 |
HIP 93155 |
17.52 |
| 2026-05-17 00:00 |
18:57:36.47 |
-22:52:30.9 |
HIP 93155 |
17.90 |
| 2026-05-17 12:00 |
18:57:34.28 |
-22:52:33.4 |
HIP 93155 |
18.28 |
| 2026-05-18 00:00 |
18:57:32.08 |
-22:52:35.8 |
HIP 93155 |
18.68 |
| 2026-05-18 12:00 |
18:57:29.85 |
-22:52:38.3 |
HIP 93155 |
19.08 |
| 2026-05-19 00:00 |
18:57:27.61 |
-22:52:40.8 |
HIP 93155 |
19.49 |
| 2026-05-19 12:00 |
18:57:25.35 |
-22:52:43.4 |
HIP 93155 |
19.92 |
| 2026-05-20 00:00 |
18:57:23.07 |
-22:52:46.0 |
HIP 92980 |
19.69 |
| 2026-05-20 12:00 |
18:57:20.77 |
-22:52:48.5 |
HIP 92980 |
19.35 |
| 2026-05-21 00:00 |
18:57:18.45 |
-22:52:51.2 |
HIP 92980 |
19.03 |
| 2026-05-21 12:00 |
18:57:16.12 |
-22:52:53.8 |
HIP 92980 |
18.71 |
| 2026-05-22 00:00 |
18:57:13.77 |
-22:52:56.4 |
HIP 92980 |
18.39 |
| 2026-05-22 12:00 |
18:57:11.40 |
-22:52:59.1 |
HIP 92980 |
18.09 |
| 2026-05-23 00:00 |
18:57:09.01 |
-22:53:01.8 |
HIP 92980 |
17.79 |
| 2026-05-23 12:00 |
18:57:06.60 |
-22:53:04.5 |
HIP 92980 |
17.51 |
| 2026-05-24 00:00 |
18:57:04.18 |
-22:53:07.3 |
HIP 92980 |
17.24 |
| 2026-05-24 12:00 |
18:57:01.74 |
-22:53:10.0 |
HIP 92980 |
16.98 |
| 2026-05-25 00:00 |
18:56:59.28 |
-22:53:12.8 |
HIP 92980 |
16.73 |
| 2026-05-25 12:00 |
18:56:56.81 |
-22:53:15.6 |
HIP 92980 |
16.50 |
| 2026-05-26 00:00 |
18:56:54.32 |
-22:53:18.4 |
HIP 92980 |
16.28 |
| 2026-05-26 12:00 |
18:56:51.82 |
-22:53:21.3 |
HIP 92980 |
16.08 |
| 2026-05-27 00:00 |
18:56:49.29 |
-22:53:24.1 |
HIP 92980 |
15.90 |
| 2026-05-27 12:00 |
18:56:46.76 |
-22:53:27.0 |
HIP 92980 |
15.73 |
| 2026-05-28 00:00 |
18:56:44.20 |
-22:53:29.9 |
HIP 92980 |
15.58 |
| 2026-05-28 12:00 |
18:56:41.63 |
-22:53:32.8 |
HIP 92980 |
15.46 |
| 2026-05-29 00:00 |
18:56:39.05 |
-22:53:35.7 |
HIP 92980 |
15.35 |
| 2026-05-29 12:00 |
18:56:36.45 |
-22:53:38.7 |
HIP 92980 |
15.27 |
| 2026-05-30 00:00 |
18:56:33.84 |
-22:53:41.6 |
HIP 92980 |
15.21 |
| 2026-05-30 12:00 |
18:56:31.21 |
-22:53:44.6 |
HIP 92980 |
15.18 |
| 2026-05-31 00:00 |
18:56:28.56 |
-22:53:47.6 |
HIP 92980 |
15.17 |
| 2026-05-31 12:00 |
18:56:25.90 |
-22:53:50.6 |
HIP 92980 |
15.18 |
| 2026-06-01 00:00 |
18:56:23.23 |
-22:53:53.6 |
HIP 92980 |
15.22 |
| 2026-06-01 12:00 |
18:56:20.54 |
-22:53:56.7 |
HIP 92980 |
15.28 |
| 2026-06-02 00:00 |
18:56:17.84 |
-22:53:59.7 |
HIP 92980 |
15.37 |