C/2003 H2 (LINEAR)
| Parameter |
Value |
| Designation |
C/2003 H2 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2003-05-17T23:15:08.225280Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:29Z |
| Obs used |
189 |
| NEO |
- |
| M1 |
14.200 |
| K1 |
10.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2003-05-22.0000000 |
| e |
0.94291012 |
| q (au) |
2.178516 |
| a (au) |
38.159402 |
| i (deg) |
74.217540 |
| Ω (om, deg) |
79.838018 |
| ω (w, deg) |
155.082163 |
| M (ma, deg) |
0.016855 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.725 + 2.527\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.725 |
| n |
2.527 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.999 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
04:35:44.45 |
-21:31:12.5 |
HIP 21414 |
10.82 |
| 2026-02-03 12:00 |
04:35:42.94 |
-21:30:42.3 |
HIP 21414 |
10.33 |
| 2026-02-04 00:00 |
04:35:41.46 |
-21:30:12.0 |
HIP 21414 |
9.86 |
| 2026-02-04 12:00 |
04:35:40.01 |
-21:29:41.6 |
HIP 21414 |
9.39 |
| 2026-02-05 00:00 |
04:35:38.59 |
-21:29:11.0 |
HIP 21414 |
8.94 |
| 2026-02-05 12:00 |
04:35:37.19 |
-21:28:40.3 |
HIP 21414 |
8.51 |
| 2026-02-06 00:00 |
04:35:35.82 |
-21:28:09.4 |
HIP 21414 |
8.09 |
| 2026-02-06 12:00 |
04:35:34.48 |
-21:27:38.4 |
HIP 21414 |
7.70 |
| 2026-02-07 00:00 |
04:35:33.17 |
-21:27:07.2 |
HIP 21414 |
7.33 |
| 2026-02-07 12:00 |
04:35:31.89 |
-21:26:35.9 |
HIP 21414 |
6.98 |
| 2026-02-08 00:00 |
04:35:30.63 |
-21:26:04.4 |
HIP 21414 |
6.67 |
| 2026-02-08 12:00 |
04:35:29.40 |
-21:25:32.8 |
HIP 21414 |
6.39 |
| 2026-02-09 00:00 |
04:35:28.20 |
-21:25:01.1 |
HIP 21414 |
6.15 |
| 2026-02-09 12:00 |
04:35:27.03 |
-21:24:29.2 |
HIP 21414 |
5.96 |
| 2026-02-10 00:00 |
04:35:25.89 |
-21:23:57.2 |
HIP 21414 |
5.81 |
| 2026-02-10 12:00 |
04:35:24.78 |
-21:23:25.1 |
HIP 21414 |
5.72 |
| 2026-02-11 00:00 |
04:35:23.69 |
-21:22:52.9 |
HIP 21414 |
5.68 |
| 2026-02-11 12:00 |
04:35:22.64 |
-21:22:20.5 |
HIP 21414 |
5.70 |
| 2026-02-12 00:00 |
04:35:21.61 |
-21:21:48.0 |
HIP 21414 |
5.77 |
| 2026-02-12 12:00 |
04:35:20.61 |
-21:21:15.4 |
HIP 21414 |
5.89 |
| 2026-02-13 00:00 |
04:35:19.64 |
-21:20:42.7 |
HIP 21414 |
6.06 |
| 2026-02-13 12:00 |
04:35:18.70 |
-21:20:09.9 |
HIP 21414 |
6.27 |
| 2026-02-14 00:00 |
04:35:17.79 |
-21:19:37.0 |
HIP 21414 |
6.53 |
| 2026-02-14 12:00 |
04:35:16.91 |
-21:19:03.9 |
HIP 21414 |
6.82 |
| 2026-02-15 00:00 |
04:35:16.06 |
-21:18:30.8 |
HIP 21414 |
7.14 |
| 2026-02-15 12:00 |
04:35:15.23 |
-21:17:57.5 |
HIP 21414 |
7.48 |
| 2026-02-16 00:00 |
04:35:14.44 |
-21:17:24.2 |
HIP 21414 |
7.85 |
| 2026-02-16 12:00 |
04:35:13.68 |
-21:16:50.7 |
HIP 21414 |
8.24 |
| 2026-02-17 00:00 |
04:35:12.94 |
-21:16:17.2 |
HIP 21414 |
8.65 |
| 2026-02-17 12:00 |
04:35:12.24 |
-21:15:43.5 |
HIP 21414 |
9.07 |
| 2026-02-18 00:00 |
04:35:11.56 |
-21:15:09.8 |
HIP 21414 |
9.50 |
| 2026-02-18 12:00 |
04:35:10.91 |
-21:14:36.0 |
HIP 21414 |
9.94 |
| 2026-02-19 00:00 |
04:35:10.30 |
-21:14:02.1 |
HIP 21414 |
10.40 |
| 2026-02-19 12:00 |
04:35:09.71 |
-21:13:28.1 |
HIP 21414 |
10.86 |
| 2026-02-20 00:00 |
04:35:09.15 |
-21:12:54.1 |
HIP 21414 |
11.33 |
| 2026-02-20 12:00 |
04:35:08.63 |
-21:12:19.9 |
HIP 21414 |
11.80 |
| 2026-02-21 00:00 |
04:35:08.13 |
-21:11:45.7 |
HIP 21414 |
12.28 |
| 2026-02-21 12:00 |
04:35:07.66 |
-21:11:11.5 |
HIP 21414 |
12.76 |
| 2026-02-22 00:00 |
04:35:07.22 |
-21:10:37.1 |
HIP 21414 |
13.25 |
| 2026-02-22 12:00 |
04:35:06.81 |
-21:10:02.7 |
HIP 21414 |
13.74 |
| 2026-02-23 00:00 |
04:35:06.43 |
-21:09:28.2 |
HIP 21414 |
14.23 |
| 2026-02-23 12:00 |
04:35:06.08 |
-21:08:53.7 |
HIP 21414 |
14.73 |
| 2026-02-24 00:00 |
04:35:05.76 |
-21:08:19.1 |
HIP 21414 |
15.23 |