C/2003 J1 (NEAT)
| Parameter |
Value |
| Designation |
C/2003 J1 (NEAT) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2003-10-10T14:30:59.739840Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:29Z |
| Obs used |
80 |
| NEO |
- |
| M1 |
11.300 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2003-07-19.0000000 |
| e |
0.99112756 |
| q (au) |
5.125425 |
| a (au) |
577.679266 |
| i (deg) |
98.313465 |
| Ω (om, deg) |
122.033180 |
| ω (w, deg) |
196.028937 |
| M (ma, deg) |
359.994065 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.067 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.067 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.502 |
| 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) |
| 2026-02-03 00:00 |
08:07:41.94 |
-06:05:40.6 |
HIP 39626 |
34.88 |
| 2026-02-03 12:00 |
08:07:39.01 |
-06:05:23.5 |
HIP 39626 |
34.48 |
| 2026-02-04 00:00 |
08:07:36.09 |
-06:05:06.2 |
HIP 39626 |
34.09 |
| 2026-02-04 12:00 |
08:07:33.18 |
-06:04:48.7 |
HIP 39626 |
33.72 |
| 2026-02-05 00:00 |
08:07:30.27 |
-06:04:31.1 |
HIP 39626 |
33.37 |
| 2026-02-05 12:00 |
08:07:27.37 |
-06:04:13.4 |
HIP 39626 |
33.04 |
| 2026-02-06 00:00 |
08:07:24.49 |
-06:03:55.5 |
HIP 39626 |
32.72 |
| 2026-02-06 12:00 |
08:07:21.60 |
-06:03:37.4 |
HIP 39626 |
32.42 |
| 2026-02-07 00:00 |
08:07:18.73 |
-06:03:19.2 |
HIP 39626 |
32.15 |
| 2026-02-07 12:00 |
08:07:15.87 |
-06:03:00.9 |
HIP 39626 |
31.89 |
| 2026-02-08 00:00 |
08:07:13.01 |
-06:02:42.4 |
HIP 39626 |
31.65 |
| 2026-02-08 12:00 |
08:07:10.17 |
-06:02:23.8 |
HIP 39626 |
31.43 |
| 2026-02-09 00:00 |
08:07:07.33 |
-06:02:05.1 |
HIP 39626 |
31.24 |
| 2026-02-09 12:00 |
08:07:04.51 |
-06:01:46.2 |
HIP 39626 |
31.06 |
| 2026-02-10 00:00 |
08:07:01.69 |
-06:01:27.1 |
HIP 39626 |
30.91 |
| 2026-02-10 12:00 |
08:06:58.88 |
-06:01:07.9 |
HIP 39626 |
30.78 |
| 2026-02-11 00:00 |
08:06:56.09 |
-06:00:48.6 |
HIP 39626 |
30.66 |
| 2026-02-11 12:00 |
08:06:53.30 |
-06:00:29.2 |
HIP 39626 |
30.58 |
| 2026-02-12 00:00 |
08:06:50.53 |
-06:00:09.6 |
HIP 39626 |
30.51 |
| 2026-02-12 12:00 |
08:06:47.76 |
-05:59:49.9 |
HIP 39626 |
30.47 |
| 2026-02-13 00:00 |
08:06:45.01 |
-05:59:30.1 |
HIP 39626 |
30.45 |
| 2026-02-13 12:00 |
08:06:42.27 |
-05:59:10.1 |
HIP 39626 |
30.45 |
| 2026-02-14 00:00 |
08:06:39.54 |
-05:58:50.0 |
HIP 39626 |
30.47 |
| 2026-02-14 12:00 |
08:06:36.82 |
-05:58:29.8 |
HIP 39626 |
30.51 |
| 2026-02-15 00:00 |
08:06:34.12 |
-05:58:09.5 |
HIP 39626 |
30.58 |
| 2026-02-15 12:00 |
08:06:31.42 |
-05:57:49.0 |
HIP 39626 |
30.67 |
| 2026-02-16 00:00 |
08:06:28.74 |
-05:57:28.4 |
HIP 39626 |
30.77 |
| 2026-02-16 12:00 |
08:06:26.07 |
-05:57:07.7 |
HIP 39626 |
30.90 |
| 2026-02-17 00:00 |
08:06:23.42 |
-05:56:46.9 |
HIP 39626 |
31.05 |
| 2026-02-17 12:00 |
08:06:20.78 |
-05:56:25.9 |
HIP 39626 |
31.22 |
| 2026-02-18 00:00 |
08:06:18.15 |
-05:56:04.9 |
HIP 39626 |
31.41 |
| 2026-02-18 12:00 |
08:06:15.54 |
-05:55:43.7 |
HIP 39626 |
31.61 |
| 2026-02-19 00:00 |
08:06:12.94 |
-05:55:22.4 |
HIP 39626 |
31.84 |
| 2026-02-19 12:00 |
08:06:10.35 |
-05:55:01.0 |
HIP 39626 |
32.08 |
| 2026-02-20 00:00 |
08:06:07.78 |
-05:54:39.5 |
HIP 39626 |
32.34 |
| 2026-02-20 12:00 |
08:06:05.23 |
-05:54:17.9 |
HIP 39626 |
32.62 |
| 2026-02-21 00:00 |
08:06:02.68 |
-05:53:56.2 |
HIP 39626 |
32.91 |
| 2026-02-21 12:00 |
08:06:00.16 |
-05:53:34.4 |
HIP 39626 |
33.22 |
| 2026-02-22 00:00 |
08:05:57.65 |
-05:53:12.5 |
HIP 39541 |
33.21 |
| 2026-02-22 12:00 |
08:05:55.15 |
-05:52:50.5 |
HIP 39541 |
32.57 |
| 2026-02-23 00:00 |
08:05:52.67 |
-05:52:28.3 |
HIP 39541 |
31.95 |
| 2026-02-23 12:00 |
08:05:50.21 |
-05:52:06.1 |
HIP 39541 |
31.32 |
| 2026-02-24 00:00 |
08:05:47.76 |
-05:51:43.8 |
HIP 39541 |
30.71 |