| Parameter |
Value |
| Designation |
C/2008 H1 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2008-03-16T10:10:14.488320Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:18Z |
| Obs used |
252 |
| NEO |
- |
| M1 |
13.300 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2008-05-16.0000000 |
| e |
0.94658786 |
| q (au) |
2.760294 |
| a (au) |
51.679144 |
| i (deg) |
75.492175 |
| Ω (om, deg) |
34.630430 |
| ω (w, deg) |
96.043511 |
| M (ma, deg) |
0.160706 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.423 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.423 |
| n |
2.000 |
| gf |
0.950 |
| gb |
-0.999 |
| k |
1.000 |
| δ90 |
9.995 |
| 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) |
| 2026-06-01 00:00 |
11:36:22.30 |
-80:35:19.6 |
HIP 57192 |
18.95 |
| 2026-06-01 12:00 |
11:36:16.72 |
-80:34:30.5 |
HIP 57192 |
18.93 |
| 2026-06-02 00:00 |
11:36:11.33 |
-80:33:41.2 |
HIP 57192 |
18.93 |
| 2026-06-02 12:00 |
11:36:06.12 |
-80:32:51.9 |
HIP 56395 |
18.81 |
| 2026-06-03 00:00 |
11:36:01.09 |
-80:32:02.4 |
HIP 56395 |
17.96 |
| 2026-06-03 12:00 |
11:35:56.23 |
-80:31:13.0 |
HIP 56395 |
17.12 |
| 2026-06-04 00:00 |
11:35:51.56 |
-80:30:23.4 |
HIP 56395 |
16.27 |
| 2026-06-04 12:00 |
11:35:47.06 |
-80:29:33.8 |
HIP 56395 |
15.43 |
| 2026-06-05 00:00 |
11:35:42.74 |
-80:28:44.2 |
HIP 56395 |
14.59 |
| 2026-06-05 12:00 |
11:35:38.60 |
-80:27:54.5 |
HIP 56395 |
13.76 |
| 2026-06-06 00:00 |
11:35:34.63 |
-80:27:04.7 |
HIP 56395 |
12.93 |
| 2026-06-06 12:00 |
11:35:30.84 |
-80:26:14.9 |
HIP 56395 |
12.10 |
| 2026-06-07 00:00 |
11:35:27.23 |
-80:25:25.1 |
HIP 56395 |
11.28 |
| 2026-06-07 12:00 |
11:35:23.79 |
-80:24:35.2 |
HIP 56395 |
10.46 |
| 2026-06-08 00:00 |
11:35:20.52 |
-80:23:45.4 |
HIP 56395 |
9.65 |
| 2026-06-08 12:00 |
11:35:17.43 |
-80:22:55.4 |
HIP 56395 |
8.84 |
| 2026-06-09 00:00 |
11:35:14.51 |
-80:22:05.5 |
HIP 56395 |
8.05 |
| 2026-06-09 12:00 |
11:35:11.77 |
-80:21:15.5 |
HIP 56395 |
7.28 |
| 2026-06-10 00:00 |
11:35:09.19 |
-80:20:25.6 |
HIP 56395 |
6.52 |
| 2026-06-10 12:00 |
11:35:06.79 |
-80:19:35.6 |
HIP 56395 |
5.79 |
| 2026-06-11 00:00 |
11:35:04.56 |
-80:18:45.6 |
HIP 56395 |
5.10 |
| 2026-06-11 12:00 |
11:35:02.50 |
-80:17:55.6 |
HIP 56395 |
4.46 |
| 2026-06-12 00:00 |
11:35:00.61 |
-80:17:05.6 |
HIP 56395 |
3.91 |
| 2026-06-12 12:00 |
11:34:58.89 |
-80:16:15.6 |
HIP 56395 |
3.48 |
| 2026-06-13 00:00 |
11:34:57.34 |
-80:15:25.7 |
HIP 56395 |
3.22 |
| 2026-06-13 12:00 |
11:34:55.95 |
-80:14:35.7 |
HIP 56395 |
3.17 |
| 2026-06-14 00:00 |
11:34:54.74 |
-80:13:45.8 |
HIP 56395 |
3.35 |
| 2026-06-14 12:00 |
11:34:53.69 |
-80:12:55.9 |
HIP 56395 |
3.71 |
| 2026-06-15 00:00 |
11:34:52.80 |
-80:12:06.0 |
HIP 56395 |
4.21 |
| 2026-06-15 12:00 |
11:34:52.09 |
-80:11:16.2 |
HIP 56395 |
4.81 |
| 2026-06-16 00:00 |
11:34:51.53 |
-80:10:26.3 |
HIP 56395 |
5.48 |
| 2026-06-16 12:00 |
11:34:51.14 |
-80:09:36.6 |
HIP 56395 |
6.18 |
| 2026-06-17 00:00 |
11:34:50.91 |
-80:08:46.9 |
HIP 56395 |
6.92 |
| 2026-06-17 12:00 |
11:34:50.85 |
-80:07:57.2 |
HIP 56395 |
7.68 |
| 2026-06-18 00:00 |
11:34:50.95 |
-80:07:07.6 |
HIP 56395 |
8.45 |
| 2026-06-18 12:00 |
11:34:51.20 |
-80:06:18.0 |
HIP 56395 |
9.23 |
| 2026-06-19 00:00 |
11:34:51.62 |
-80:05:28.5 |
HIP 56395 |
10.02 |
| 2026-06-19 12:00 |
11:34:52.19 |
-80:04:39.1 |
HIP 56395 |
10.82 |
| 2026-06-20 00:00 |
11:34:52.92 |
-80:03:49.7 |
HIP 56395 |
11.62 |
| 2026-06-20 12:00 |
11:34:53.81 |
-80:03:00.5 |
HIP 56395 |
12.43 |
| 2026-06-21 00:00 |
11:34:54.86 |
-80:02:11.3 |
HIP 56395 |
13.23 |
| 2026-06-21 12:00 |
11:34:56.05 |
-80:01:22.1 |
HIP 56395 |
14.04 |
| 2026-06-22 00:00 |
11:34:57.41 |
-80:00:33.1 |
HIP 56395 |
14.85 |