| 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) |
| 2026-03-26 00:00 |
18:59:17.94 |
-22:51:04.8 |
HIP 93155 |
15.67 |
| 2026-03-26 12:00 |
18:59:18.25 |
-22:51:03.9 |
HIP 93155 |
15.71 |
| 2026-03-27 00:00 |
18:59:18.55 |
-22:51:02.9 |
HIP 93155 |
15.75 |
| 2026-03-27 12:00 |
18:59:18.81 |
-22:51:02.0 |
HIP 93155 |
15.78 |
| 2026-03-28 00:00 |
18:59:19.05 |
-22:51:01.2 |
HIP 93155 |
15.81 |
| 2026-03-28 12:00 |
18:59:19.26 |
-22:51:00.4 |
HIP 93155 |
15.83 |
| 2026-03-29 00:00 |
18:59:19.45 |
-22:50:59.6 |
HIP 93155 |
15.86 |
| 2026-03-29 12:00 |
18:59:19.62 |
-22:50:58.8 |
HIP 93155 |
15.87 |
| 2026-03-30 00:00 |
18:59:19.75 |
-22:50:58.1 |
HIP 93155 |
15.89 |
| 2026-03-30 12:00 |
18:59:19.86 |
-22:50:57.4 |
HIP 93155 |
15.90 |
| 2026-03-31 00:00 |
18:59:19.95 |
-22:50:56.8 |
HIP 93155 |
15.90 |
| 2026-03-31 12:00 |
18:59:20.01 |
-22:50:56.2 |
HIP 93155 |
15.91 |
| 2026-04-01 00:00 |
18:59:20.05 |
-22:50:55.6 |
HIP 93155 |
15.91 |
| 2026-04-01 12:00 |
18:59:20.05 |
-22:50:55.1 |
HIP 93155 |
15.90 |
| 2026-04-02 00:00 |
18:59:20.04 |
-22:50:54.6 |
HIP 93155 |
15.89 |
| 2026-04-02 12:00 |
18:59:19.99 |
-22:50:54.1 |
HIP 93155 |
15.88 |
| 2026-04-03 00:00 |
18:59:19.93 |
-22:50:53.7 |
HIP 93155 |
15.86 |
| 2026-04-03 12:00 |
18:59:19.83 |
-22:50:53.3 |
HIP 93155 |
15.84 |
| 2026-04-04 00:00 |
18:59:19.71 |
-22:50:53.0 |
HIP 93155 |
15.82 |
| 2026-04-04 12:00 |
18:59:19.57 |
-22:50:52.7 |
HIP 93155 |
15.79 |
| 2026-04-05 00:00 |
18:59:19.40 |
-22:50:52.4 |
HIP 93155 |
15.76 |
| 2026-04-05 12:00 |
18:59:19.20 |
-22:50:52.1 |
HIP 93155 |
15.73 |
| 2026-04-06 00:00 |
18:59:18.98 |
-22:50:51.9 |
HIP 93155 |
15.69 |
| 2026-04-06 12:00 |
18:59:18.73 |
-22:50:51.8 |
HIP 93155 |
15.65 |
| 2026-04-07 00:00 |
18:59:18.45 |
-22:50:51.6 |
HIP 93155 |
15.60 |
| 2026-04-07 12:00 |
18:59:18.15 |
-22:50:51.5 |
HIP 93155 |
15.55 |
| 2026-04-08 00:00 |
18:59:17.83 |
-22:50:51.5 |
HIP 93155 |
15.50 |
| 2026-04-08 12:00 |
18:59:17.48 |
-22:50:51.4 |
HIP 93155 |
15.44 |
| 2026-04-09 00:00 |
18:59:17.10 |
-22:50:51.5 |
HIP 93155 |
15.38 |
| 2026-04-09 12:00 |
18:59:16.70 |
-22:50:51.5 |
HIP 93155 |
15.32 |
| 2026-04-10 00:00 |
18:59:16.27 |
-22:50:51.6 |
HIP 93155 |
15.25 |
| 2026-04-10 12:00 |
18:59:15.81 |
-22:50:51.7 |
HIP 93155 |
15.18 |
| 2026-04-11 00:00 |
18:59:15.33 |
-22:50:51.9 |
HIP 93155 |
15.10 |
| 2026-04-11 12:00 |
18:59:14.82 |
-22:50:52.0 |
HIP 93155 |
15.03 |
| 2026-04-12 00:00 |
18:59:14.29 |
-22:50:52.3 |
HIP 93155 |
14.95 |
| 2026-04-12 12:00 |
18:59:13.73 |
-22:50:52.5 |
HIP 93155 |
14.87 |
| 2026-04-13 00:00 |
18:59:13.15 |
-22:50:52.8 |
HIP 93155 |
14.78 |
| 2026-04-13 12:00 |
18:59:12.54 |
-22:50:53.2 |
HIP 93155 |
14.69 |
| 2026-04-14 00:00 |
18:59:11.90 |
-22:50:53.5 |
HIP 93155 |
14.60 |
| 2026-04-14 12:00 |
18:59:11.24 |
-22:50:53.9 |
HIP 93155 |
14.51 |
| 2026-04-15 00:00 |
18:59:10.56 |
-22:50:54.4 |
HIP 93155 |
14.41 |
| 2026-04-15 12:00 |
18:59:09.84 |
-22:50:54.9 |
HIP 93155 |
14.32 |
| 2026-04-16 00:00 |
18:59:09.11 |
-22:50:55.4 |
HIP 93155 |
14.22 |