C/2003 H1 (LINEAR)
| Parameter |
Value |
| Designation |
C/2003 H1 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2004-02-22T14:57:51.929280Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:29Z |
| Obs used |
1890 |
| NEO |
- |
| M1 |
11.000 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2003-08-30.0000000 |
| e |
0.99915679 |
| q (au) |
2.239626 |
| a (au) |
2656.070310 |
| i (deg) |
138.667213 |
| Ω (om, deg) |
19.000486 |
| ω (w, deg) |
196.139594 |
| M (ma, deg) |
359.998728 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.871 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.871 |
| n |
2.000 |
| gf |
0.989 |
| gb |
-0.730 |
| k |
0.800 |
| δ90 |
10.000 |
| 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 |
| 2003-04-24 |
2004-02-21 |
+3.5205 |
-2.057 |
| 2004-02-23 |
2004-06-11 |
+43.1351 |
-15.432 |
| 2004-06-11 |
2005-02-07 |
+10.7171 |
-2.190 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
01:45:15.07 |
+03:32:17.9 |
HIP 8211 |
10.55 |
| 2026-02-03 12:00 |
01:45:15.65 |
+03:32:27.9 |
HIP 8211 |
10.33 |
| 2026-02-04 00:00 |
01:45:16.25 |
+03:32:38.0 |
HIP 8211 |
10.11 |
| 2026-02-04 12:00 |
01:45:16.88 |
+03:32:48.3 |
HIP 8211 |
9.88 |
| 2026-02-05 00:00 |
01:45:17.52 |
+03:32:58.6 |
HIP 8211 |
9.64 |
| 2026-02-05 12:00 |
01:45:18.19 |
+03:33:09.0 |
HIP 8211 |
9.40 |
| 2026-02-06 00:00 |
01:45:18.88 |
+03:33:19.6 |
HIP 8211 |
9.15 |
| 2026-02-06 12:00 |
01:45:19.59 |
+03:33:30.2 |
HIP 8211 |
8.90 |
| 2026-02-07 00:00 |
01:45:20.32 |
+03:33:41.0 |
HIP 8211 |
8.65 |
| 2026-02-07 12:00 |
01:45:21.07 |
+03:33:51.8 |
HIP 8211 |
8.39 |
| 2026-02-08 00:00 |
01:45:21.84 |
+03:34:02.8 |
HIP 8211 |
8.12 |
| 2026-02-08 12:00 |
01:45:22.64 |
+03:34:13.8 |
HIP 8211 |
7.85 |
| 2026-02-09 00:00 |
01:45:23.46 |
+03:34:25.0 |
HIP 8211 |
7.58 |
| 2026-02-09 12:00 |
01:45:24.29 |
+03:34:36.2 |
HIP 8211 |
7.30 |
| 2026-02-10 00:00 |
01:45:25.15 |
+03:34:47.6 |
HIP 8211 |
7.02 |
| 2026-02-10 12:00 |
01:45:26.03 |
+03:34:59.1 |
HIP 8211 |
6.73 |
| 2026-02-11 00:00 |
01:45:26.93 |
+03:35:10.6 |
HIP 8211 |
6.43 |
| 2026-02-11 12:00 |
01:45:27.86 |
+03:35:22.3 |
HIP 8211 |
6.14 |
| 2026-02-12 00:00 |
01:45:28.80 |
+03:35:34.0 |
HIP 8211 |
5.84 |
| 2026-02-12 12:00 |
01:45:29.76 |
+03:35:45.8 |
HIP 8211 |
5.53 |
| 2026-02-13 00:00 |
01:45:30.75 |
+03:35:57.8 |
HIP 8211 |
5.22 |
| 2026-02-13 12:00 |
01:45:31.75 |
+03:36:09.8 |
HIP 8211 |
4.91 |
| 2026-02-14 00:00 |
01:45:32.77 |
+03:36:21.9 |
HIP 8211 |
4.59 |
| 2026-02-14 12:00 |
01:45:33.82 |
+03:36:34.1 |
HIP 8211 |
4.27 |
| 2026-02-15 00:00 |
01:45:34.88 |
+03:36:46.4 |
HIP 8211 |
3.95 |
| 2026-02-15 12:00 |
01:45:35.97 |
+03:36:58.8 |
HIP 8211 |
3.63 |
| 2026-02-16 00:00 |
01:45:37.07 |
+03:37:11.3 |
HIP 8211 |
3.31 |
| 2026-02-16 12:00 |
01:45:38.20 |
+03:37:23.9 |
HIP 8211 |
2.99 |
| 2026-02-17 00:00 |
01:45:39.34 |
+03:37:36.5 |
HIP 8211 |
2.67 |
| 2026-02-17 12:00 |
01:45:40.51 |
+03:37:49.2 |
HIP 8211 |
2.37 |
| 2026-02-18 00:00 |
01:45:41.69 |
+03:38:02.1 |
HIP 8211 |
2.07 |
| 2026-02-18 12:00 |
01:45:42.89 |
+03:38:15.0 |
HIP 8211 |
1.80 |
| 2026-02-19 00:00 |
01:45:44.12 |
+03:38:28.0 |
HIP 8211 |
1.57 |
| 2026-02-19 12:00 |
01:45:45.36 |
+03:38:41.0 |
HIP 8211 |
1.40 |
| 2026-02-20 00:00 |
01:45:46.62 |
+03:38:54.2 |
HIP 8211 |
1.33 |
| 2026-02-20 12:00 |
01:45:47.90 |
+03:39:07.4 |
HIP 8211 |
1.36 |
| 2026-02-21 00:00 |
01:45:49.20 |
+03:39:20.7 |
HIP 8211 |
1.50 |
| 2026-02-21 12:00 |
01:45:50.51 |
+03:39:34.1 |
HIP 8211 |
1.73 |
| 2026-02-22 00:00 |
01:45:51.85 |
+03:39:47.5 |
HIP 8211 |
2.01 |
| 2026-02-22 12:00 |
01:45:53.20 |
+03:40:01.0 |
HIP 8211 |
2.34 |
| 2026-02-23 00:00 |
01:45:54.57 |
+03:40:14.6 |
HIP 8211 |
2.69 |
| 2026-02-23 12:00 |
01:45:55.96 |
+03:40:28.3 |
HIP 8211 |
3.06 |
| 2026-02-24 00:00 |
01:45:57.37 |
+03:40:42.1 |
HIP 8211 |
3.44 |