| 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) |
| 2026-07-29 00:00 |
06:15:00.02 |
+09:00:36.8 |
HIP 29787 |
19.26 |
| 2026-07-29 12:00 |
06:15:02.31 |
+09:00:31.7 |
HIP 29787 |
18.70 |
| 2026-07-30 00:00 |
06:15:04.58 |
+09:00:26.6 |
HIP 29787 |
18.14 |
| 2026-07-30 12:00 |
06:15:06.85 |
+09:00:21.4 |
HIP 29787 |
17.59 |
| 2026-07-31 00:00 |
06:15:09.10 |
+09:00:16.2 |
HIP 29787 |
17.04 |
| 2026-07-31 12:00 |
06:15:11.34 |
+09:00:10.9 |
HIP 29787 |
16.50 |
| 2026-08-01 00:00 |
06:15:13.56 |
+09:00:05.5 |
HIP 29787 |
15.96 |
| 2026-08-01 12:00 |
06:15:15.77 |
+09:00:00.0 |
HIP 29787 |
15.43 |
| 2026-08-02 00:00 |
06:15:17.97 |
+08:59:54.5 |
HIP 29787 |
14.90 |
| 2026-08-02 12:00 |
06:15:20.16 |
+08:59:48.9 |
HIP 29787 |
14.37 |
| 2026-08-03 00:00 |
06:15:22.33 |
+08:59:43.3 |
HIP 29787 |
13.86 |
| 2026-08-03 12:00 |
06:15:24.49 |
+08:59:37.5 |
HIP 29787 |
13.34 |
| 2026-08-04 00:00 |
06:15:26.64 |
+08:59:31.8 |
HIP 29787 |
12.83 |
| 2026-08-04 12:00 |
06:15:28.77 |
+08:59:25.9 |
HIP 29787 |
12.33 |
| 2026-08-05 00:00 |
06:15:30.89 |
+08:59:20.0 |
HIP 29787 |
11.84 |
| 2026-08-05 12:00 |
06:15:33.00 |
+08:59:14.0 |
HIP 29787 |
11.35 |
| 2026-08-06 00:00 |
06:15:35.09 |
+08:59:08.0 |
HIP 29787 |
10.87 |
| 2026-08-06 12:00 |
06:15:37.16 |
+08:59:01.9 |
HIP 29787 |
10.40 |
| 2026-08-07 00:00 |
06:15:39.22 |
+08:58:55.8 |
HIP 29787 |
9.93 |
| 2026-08-07 12:00 |
06:15:41.27 |
+08:58:49.6 |
HIP 29787 |
9.48 |
| 2026-08-08 00:00 |
06:15:43.30 |
+08:58:43.3 |
HIP 29787 |
9.03 |
| 2026-08-08 12:00 |
06:15:45.32 |
+08:58:36.9 |
HIP 29787 |
8.60 |
| 2026-08-09 00:00 |
06:15:47.32 |
+08:58:30.5 |
HIP 29787 |
8.18 |
| 2026-08-09 12:00 |
06:15:49.31 |
+08:58:24.1 |
HIP 29787 |
7.78 |
| 2026-08-10 00:00 |
06:15:51.28 |
+08:58:17.6 |
HIP 29787 |
7.39 |
| 2026-08-10 12:00 |
06:15:53.24 |
+08:58:11.0 |
HIP 29787 |
7.01 |
| 2026-08-11 00:00 |
06:15:55.18 |
+08:58:04.4 |
HIP 29787 |
6.66 |
| 2026-08-11 12:00 |
06:15:57.10 |
+08:57:57.7 |
HIP 29787 |
6.33 |
| 2026-08-12 00:00 |
06:15:59.01 |
+08:57:50.9 |
HIP 29787 |
6.02 |
| 2026-08-12 12:00 |
06:16:00.90 |
+08:57:44.1 |
HIP 29787 |
5.75 |
| 2026-08-13 00:00 |
06:16:02.78 |
+08:57:37.3 |
HIP 29787 |
5.50 |
| 2026-08-13 12:00 |
06:16:04.64 |
+08:57:30.4 |
HIP 29787 |
5.29 |
| 2026-08-14 00:00 |
06:16:06.48 |
+08:57:23.4 |
HIP 29787 |
5.12 |
| 2026-08-14 12:00 |
06:16:08.31 |
+08:57:16.4 |
HIP 29787 |
4.99 |
| 2026-08-15 00:00 |
06:16:10.11 |
+08:57:09.3 |
HIP 29787 |
4.90 |
| 2026-08-15 12:00 |
06:16:11.91 |
+08:57:02.2 |
HIP 29787 |
4.86 |
| 2026-08-16 00:00 |
06:16:13.68 |
+08:56:55.0 |
HIP 29787 |
4.86 |
| 2026-08-16 12:00 |
06:16:15.44 |
+08:56:47.8 |
HIP 29787 |
4.91 |
| 2026-08-17 00:00 |
06:16:17.18 |
+08:56:40.5 |
HIP 29787 |
4.99 |
| 2026-08-17 12:00 |
06:16:18.90 |
+08:56:33.2 |
HIP 29787 |
5.12 |
| 2026-08-18 00:00 |
06:16:20.60 |
+08:56:25.8 |
HIP 29787 |
5.28 |
| 2026-08-18 12:00 |
06:16:22.29 |
+08:56:18.4 |
HIP 29787 |
5.47 |
| 2026-08-19 00:00 |
06:16:23.96 |
+08:56:10.9 |
HIP 29787 |
5.68 |