| Parameter |
Value |
| Designation |
C/2003 F1 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2003-06-28T11:02:31.318080Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:27Z |
| Obs used |
1150 |
| NEO |
- |
| M1 |
8.300 |
| K1 |
10.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2003-05-31.0000000 |
| e |
0.80603402 |
| q (au) |
4.007799 |
| a (au) |
20.662380 |
| i (deg) |
70.221513 |
| Ω (om, deg) |
87.487652 |
| ω (w, deg) |
121.188132 |
| M (ma, deg) |
359.701345 |
Magnitude
Scatter + Global Linear
$$
M_a = (4.239 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
4.239 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| k |
1.000 |
| 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) |
| 2026-09-20 00:00 |
04:03:49.95 |
-50:21:16.8 |
HIP 18817 |
20.25 |
| 2026-09-20 12:00 |
04:03:47.64 |
-50:22:03.9 |
HIP 18817 |
19.57 |
| 2026-09-21 00:00 |
04:03:45.28 |
-50:22:50.8 |
HIP 18817 |
18.90 |
| 2026-09-21 12:00 |
04:03:42.87 |
-50:23:37.5 |
HIP 18817 |
18.24 |
| 2026-09-22 00:00 |
04:03:40.41 |
-50:24:24.1 |
HIP 18817 |
17.60 |
| 2026-09-22 12:00 |
04:03:37.90 |
-50:25:10.5 |
HIP 18817 |
16.96 |
| 2026-09-23 00:00 |
04:03:35.35 |
-50:25:56.7 |
HIP 18817 |
16.35 |
| 2026-09-23 12:00 |
04:03:32.75 |
-50:26:42.7 |
HIP 18817 |
15.75 |
| 2026-09-24 00:00 |
04:03:30.10 |
-50:27:28.6 |
HIP 18817 |
15.16 |
| 2026-09-24 12:00 |
04:03:27.41 |
-50:28:14.2 |
HIP 18817 |
14.61 |
| 2026-09-25 00:00 |
04:03:24.67 |
-50:28:59.6 |
HIP 18817 |
14.07 |
| 2026-09-25 12:00 |
04:03:21.88 |
-50:29:44.9 |
HIP 18817 |
13.57 |
| 2026-09-26 00:00 |
04:03:19.04 |
-50:30:29.9 |
HIP 18817 |
13.10 |
| 2026-09-26 12:00 |
04:03:16.16 |
-50:31:14.7 |
HIP 18817 |
12.66 |
| 2026-09-27 00:00 |
04:03:13.23 |
-50:31:59.3 |
HIP 18817 |
12.26 |
| 2026-09-27 12:00 |
04:03:10.26 |
-50:32:43.7 |
HIP 18817 |
11.91 |
| 2026-09-28 00:00 |
04:03:07.24 |
-50:33:27.9 |
HIP 18817 |
11.60 |
| 2026-09-28 12:00 |
04:03:04.17 |
-50:34:11.8 |
HIP 18817 |
11.35 |
| 2026-09-29 00:00 |
04:03:01.06 |
-50:34:55.5 |
HIP 18817 |
11.15 |
| 2026-09-29 12:00 |
04:02:57.91 |
-50:35:39.0 |
HIP 18817 |
11.01 |
| 2026-09-30 00:00 |
04:02:54.70 |
-50:36:22.3 |
HIP 18817 |
10.93 |
| 2026-09-30 12:00 |
04:02:51.46 |
-50:37:05.3 |
HIP 18817 |
10.92 |
| 2026-10-01 00:00 |
04:02:48.17 |
-50:37:48.0 |
HIP 18817 |
10.97 |
| 2026-10-01 12:00 |
04:02:44.83 |
-50:38:30.5 |
HIP 18817 |
11.08 |
| 2026-10-02 00:00 |
04:02:41.45 |
-50:39:12.8 |
HIP 18817 |
11.25 |
| 2026-10-02 12:00 |
04:02:38.03 |
-50:39:54.8 |
HIP 18817 |
11.49 |
| 2026-10-03 00:00 |
04:02:34.56 |
-50:40:36.5 |
HIP 18817 |
11.77 |
| 2026-10-03 12:00 |
04:02:31.05 |
-50:41:18.0 |
HIP 18817 |
12.11 |
| 2026-10-04 00:00 |
04:02:27.49 |
-50:41:59.2 |
HIP 18817 |
12.49 |
| 2026-10-04 12:00 |
04:02:23.89 |
-50:42:40.1 |
HIP 18817 |
12.92 |
| 2026-10-05 00:00 |
04:02:20.25 |
-50:43:20.8 |
HIP 18817 |
13.39 |
| 2026-10-05 12:00 |
04:02:16.56 |
-50:44:01.2 |
HIP 18817 |
13.89 |
| 2026-10-06 00:00 |
04:02:12.84 |
-50:44:41.3 |
HIP 18817 |
14.43 |
| 2026-10-06 12:00 |
04:02:09.07 |
-50:45:21.1 |
HIP 18785 |
13.67 |
| 2026-10-07 00:00 |
04:02:05.25 |
-50:46:00.6 |
HIP 18785 |
12.81 |
| 2026-10-07 12:00 |
04:02:01.40 |
-50:46:39.8 |
HIP 18785 |
11.96 |
| 2026-10-08 00:00 |
04:01:57.50 |
-50:47:18.7 |
HIP 18785 |
11.12 |
| 2026-10-08 12:00 |
04:01:53.57 |
-50:47:57.3 |
HIP 18785 |
10.29 |
| 2026-10-09 00:00 |
04:01:49.59 |
-50:48:35.6 |
HIP 18785 |
9.47 |
| 2026-10-09 12:00 |
04:01:45.57 |
-50:49:13.6 |
HIP 18785 |
8.68 |
| 2026-10-10 00:00 |
04:01:41.51 |
-50:49:51.3 |
HIP 18785 |
7.90 |
| 2026-10-10 12:00 |
04:01:37.41 |
-50:50:28.6 |
HIP 18785 |
7.16 |
| 2026-10-11 00:00 |
04:01:33.28 |
-50:51:05.6 |
HIP 18785 |
6.47 |