| Parameter |
Value |
| Designation |
C/2003 T4 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2005-04-03T15:45:28.166400Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:34Z |
| Obs used |
955 |
| NEO |
- |
| M1 |
9.200 |
| K1 |
6.750 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2004-10-20.0000000 |
| e |
1.00047448 |
| q (au) |
0.849741 |
| a (au) |
-1790.885861 |
| i (deg) |
86.761193 |
| Ω (om, deg) |
93.902875 |
| ω (w, deg) |
181.679273 |
| M (ma, deg) |
-0.002154 |
Magnitude
Scatter + Global Linear
$$
M_a = (7.953 + 4.136\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
7.953 |
| n |
4.136 |
| gf |
0.800 |
| gb |
-1.000 |
| k |
0.988 |
| δ90 |
1.000 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2003-10-13 |
2004-05-22 |
+1.4145 |
-1.791 |
| 2004-05-22 |
2004-09-06 |
+1.1723 |
-1.351 |
| 2004-09-06 |
2005-04-02 |
-1.5294 |
-0.289 |
| 2005-04-03 |
2005-05-04 |
+13.8649 |
+1.663 |
| 2005-05-04 |
2006-03-25 |
+0.8135 |
+1.141 |
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 |
06:17:28.72 |
+08:47:01.8 |
HIP 29896 |
16.18 |
| 2026-09-20 12:00 |
06:17:29.01 |
+08:46:52.6 |
HIP 29896 |
16.02 |
| 2026-09-21 00:00 |
06:17:29.28 |
+08:46:43.4 |
HIP 29896 |
15.85 |
| 2026-09-21 12:00 |
06:17:29.52 |
+08:46:34.2 |
HIP 29896 |
15.69 |
| 2026-09-22 00:00 |
06:17:29.74 |
+08:46:25.0 |
HIP 29896 |
15.53 |
| 2026-09-22 12:00 |
06:17:29.94 |
+08:46:15.8 |
HIP 29896 |
15.37 |
| 2026-09-23 00:00 |
06:17:30.11 |
+08:46:06.6 |
HIP 29896 |
15.21 |
| 2026-09-23 12:00 |
06:17:30.26 |
+08:45:57.4 |
HIP 29896 |
15.05 |
| 2026-09-24 00:00 |
06:17:30.39 |
+08:45:48.2 |
HIP 29896 |
14.90 |
| 2026-09-24 12:00 |
06:17:30.49 |
+08:45:39.0 |
HIP 29896 |
14.74 |
| 2026-09-25 00:00 |
06:17:30.57 |
+08:45:29.8 |
HIP 29896 |
14.59 |
| 2026-09-25 12:00 |
06:17:30.62 |
+08:45:20.6 |
HIP 29896 |
14.43 |
| 2026-09-26 00:00 |
06:17:30.65 |
+08:45:11.5 |
HIP 29896 |
14.28 |
| 2026-09-26 12:00 |
06:17:30.66 |
+08:45:02.3 |
HIP 29896 |
14.13 |
| 2026-09-27 00:00 |
06:17:30.65 |
+08:44:53.1 |
HIP 29896 |
13.98 |
| 2026-09-27 12:00 |
06:17:30.61 |
+08:44:43.9 |
HIP 29896 |
13.84 |
| 2026-09-28 00:00 |
06:17:30.54 |
+08:44:34.8 |
HIP 29896 |
13.69 |
| 2026-09-28 12:00 |
06:17:30.45 |
+08:44:25.6 |
HIP 29896 |
13.55 |
| 2026-09-29 00:00 |
06:17:30.34 |
+08:44:16.5 |
HIP 29896 |
13.40 |
| 2026-09-29 12:00 |
06:17:30.20 |
+08:44:07.3 |
HIP 29896 |
13.26 |
| 2026-09-30 00:00 |
06:17:30.05 |
+08:43:58.2 |
HIP 29896 |
13.12 |
| 2026-09-30 12:00 |
06:17:29.86 |
+08:43:49.1 |
HIP 29896 |
12.99 |
| 2026-10-01 00:00 |
06:17:29.65 |
+08:43:40.0 |
HIP 29896 |
12.85 |
| 2026-10-01 12:00 |
06:17:29.42 |
+08:43:30.9 |
HIP 29896 |
12.72 |
| 2026-10-02 00:00 |
06:17:29.17 |
+08:43:21.8 |
HIP 29896 |
12.59 |
| 2026-10-02 12:00 |
06:17:28.89 |
+08:43:12.8 |
HIP 29896 |
12.46 |
| 2026-10-03 00:00 |
06:17:28.58 |
+08:43:03.7 |
HIP 29896 |
12.33 |
| 2026-10-03 12:00 |
06:17:28.26 |
+08:42:54.7 |
HIP 29896 |
12.21 |
| 2026-10-04 00:00 |
06:17:27.90 |
+08:42:45.7 |
HIP 29896 |
12.09 |
| 2026-10-04 12:00 |
06:17:27.53 |
+08:42:36.7 |
HIP 29896 |
11.98 |
| 2026-10-05 00:00 |
06:17:27.13 |
+08:42:27.7 |
HIP 29896 |
11.86 |
| 2026-10-05 12:00 |
06:17:26.70 |
+08:42:18.8 |
HIP 29896 |
11.75 |
| 2026-10-06 00:00 |
06:17:26.26 |
+08:42:09.8 |
HIP 29896 |
11.65 |
| 2026-10-06 12:00 |
06:17:25.78 |
+08:42:00.9 |
HIP 29896 |
11.55 |
| 2026-10-07 00:00 |
06:17:25.29 |
+08:41:52.0 |
HIP 29896 |
11.46 |
| 2026-10-07 12:00 |
06:17:24.77 |
+08:41:43.1 |
HIP 29896 |
11.37 |
| 2026-10-08 00:00 |
06:17:24.22 |
+08:41:34.3 |
HIP 29896 |
11.28 |
| 2026-10-08 12:00 |
06:17:23.65 |
+08:41:25.4 |
HIP 29896 |
11.20 |
| 2026-10-09 00:00 |
06:17:23.06 |
+08:41:16.6 |
HIP 29896 |
11.13 |
| 2026-10-09 12:00 |
06:17:22.44 |
+08:41:07.9 |
HIP 29896 |
11.06 |
| 2026-10-10 00:00 |
06:17:21.80 |
+08:40:59.1 |
HIP 29896 |
11.00 |
| 2026-10-10 12:00 |
06:17:21.14 |
+08:40:50.4 |
HIP 29896 |
10.95 |
| 2026-10-11 00:00 |
06:17:20.45 |
+08:40:41.7 |
HIP 29896 |
10.91 |