| 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) |
| 2026-09-20 00:00 |
18:47:01.77 |
-23:03:09.5 |
HIP 92240 |
17.40 |
| 2026-09-20 12:00 |
18:47:00.96 |
-23:03:09.7 |
HIP 92240 |
17.53 |
| 2026-09-21 00:00 |
18:47:00.18 |
-23:03:10.0 |
HIP 92240 |
17.65 |
| 2026-09-21 12:00 |
18:46:59.43 |
-23:03:10.2 |
HIP 92240 |
17.78 |
| 2026-09-22 00:00 |
18:46:58.70 |
-23:03:10.4 |
HIP 92240 |
17.90 |
| 2026-09-22 12:00 |
18:46:58.00 |
-23:03:10.5 |
HIP 92240 |
18.01 |
| 2026-09-23 00:00 |
18:46:57.32 |
-23:03:10.7 |
HIP 92240 |
18.13 |
| 2026-09-23 12:00 |
18:46:56.66 |
-23:03:10.8 |
HIP 92240 |
18.24 |
| 2026-09-24 00:00 |
18:46:56.04 |
-23:03:10.9 |
HIP 92240 |
18.34 |
| 2026-09-24 12:00 |
18:46:55.43 |
-23:03:10.9 |
HIP 92240 |
18.45 |
| 2026-09-25 00:00 |
18:46:54.85 |
-23:03:10.9 |
HIP 92240 |
18.55 |
| 2026-09-25 12:00 |
18:46:54.30 |
-23:03:10.9 |
HIP 92240 |
18.64 |
| 2026-09-26 00:00 |
18:46:53.77 |
-23:03:10.9 |
HIP 92240 |
18.73 |
| 2026-09-26 12:00 |
18:46:53.27 |
-23:03:10.8 |
HIP 92240 |
18.82 |
| 2026-09-27 00:00 |
18:46:52.80 |
-23:03:10.7 |
HIP 92240 |
18.91 |
| 2026-09-27 12:00 |
18:46:52.34 |
-23:03:10.6 |
HIP 92240 |
18.99 |
| 2026-09-28 00:00 |
18:46:51.92 |
-23:03:10.4 |
HIP 92240 |
19.06 |
| 2026-09-28 12:00 |
18:46:51.52 |
-23:03:10.3 |
HIP 92240 |
19.13 |
| 2026-09-29 00:00 |
18:46:51.14 |
-23:03:10.1 |
HIP 92240 |
19.20 |
| 2026-09-29 12:00 |
18:46:50.79 |
-23:03:09.8 |
HIP 92240 |
19.27 |
| 2026-09-30 00:00 |
18:46:50.47 |
-23:03:09.6 |
HIP 92240 |
19.33 |
| 2026-09-30 12:00 |
18:46:50.17 |
-23:03:09.3 |
HIP 92240 |
19.38 |
| 2026-10-01 00:00 |
18:46:49.90 |
-23:03:09.0 |
HIP 92240 |
19.44 |
| 2026-10-01 12:00 |
18:46:49.65 |
-23:03:08.6 |
HIP 92240 |
19.48 |
| 2026-10-02 00:00 |
18:46:49.43 |
-23:03:08.2 |
HIP 92240 |
19.53 |
| 2026-10-02 12:00 |
18:46:49.23 |
-23:03:07.8 |
HIP 92240 |
19.57 |
| 2026-10-03 00:00 |
18:46:49.06 |
-23:03:07.4 |
HIP 92240 |
19.60 |
| 2026-10-03 12:00 |
18:46:48.91 |
-23:03:07.0 |
HIP 92240 |
19.63 |
| 2026-10-04 00:00 |
18:46:48.79 |
-23:03:06.5 |
HIP 92240 |
19.66 |
| 2026-10-04 12:00 |
18:46:48.70 |
-23:03:06.0 |
HIP 92240 |
19.68 |
| 2026-10-05 00:00 |
18:46:48.63 |
-23:03:05.4 |
HIP 92240 |
19.70 |
| 2026-10-05 12:00 |
18:46:48.59 |
-23:03:04.8 |
HIP 92240 |
19.71 |
| 2026-10-06 00:00 |
18:46:48.57 |
-23:03:04.2 |
HIP 92240 |
19.72 |
| 2026-10-06 12:00 |
18:46:48.58 |
-23:03:03.6 |
HIP 92240 |
19.73 |
| 2026-10-07 00:00 |
18:46:48.61 |
-23:03:03.0 |
HIP 92240 |
19.73 |
| 2026-10-07 12:00 |
18:46:48.67 |
-23:03:02.3 |
HIP 92240 |
19.73 |
| 2026-10-08 00:00 |
18:46:48.76 |
-23:03:01.6 |
HIP 92240 |
19.72 |
| 2026-10-08 12:00 |
18:46:48.87 |
-23:03:00.8 |
HIP 92240 |
19.71 |
| 2026-10-09 00:00 |
18:46:49.00 |
-23:03:00.1 |
HIP 92240 |
19.69 |
| 2026-10-09 12:00 |
18:46:49.16 |
-23:02:59.3 |
HIP 92240 |
19.67 |
| 2026-10-10 00:00 |
18:46:49.35 |
-23:02:58.4 |
HIP 92240 |
19.64 |
| 2026-10-10 12:00 |
18:46:49.56 |
-23:02:57.6 |
HIP 92240 |
19.62 |
| 2026-10-11 00:00 |
18:46:49.80 |
-23:02:56.7 |
HIP 92240 |
19.58 |