| 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 |
0.963 |
| gb |
-0.998 |
| k |
1.000 |
| δ90 |
9.997 |
| 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 |
08:04:50.47 |
-04:42:32.4 |
HIP 39483 |
12.29 |
| 2026-06-01 12:00 |
08:04:52.34 |
-04:42:20.5 |
HIP 39483 |
12.79 |
| 2026-06-02 00:00 |
08:04:54.23 |
-04:42:08.8 |
HIP 39483 |
13.28 |
| 2026-06-02 12:00 |
08:04:56.14 |
-04:41:57.2 |
HIP 39483 |
13.79 |
| 2026-06-03 00:00 |
08:04:58.06 |
-04:41:45.7 |
HIP 39483 |
14.29 |
| 2026-06-03 12:00 |
08:05:00.00 |
-04:41:34.4 |
HIP 39483 |
14.80 |
| 2026-06-04 00:00 |
08:05:01.95 |
-04:41:23.3 |
HIP 39483 |
15.31 |
| 2026-06-04 12:00 |
08:05:03.93 |
-04:41:12.4 |
HIP 39483 |
15.82 |
| 2026-06-05 00:00 |
08:05:05.91 |
-04:41:01.6 |
HIP 39483 |
16.34 |
| 2026-06-05 12:00 |
08:05:07.92 |
-04:40:50.9 |
HIP 39483 |
16.86 |
| 2026-06-06 00:00 |
08:05:09.94 |
-04:40:40.4 |
HIP 39483 |
17.38 |
| 2026-06-06 12:00 |
08:05:11.98 |
-04:40:30.1 |
HIP 39483 |
17.90 |
| 2026-06-07 00:00 |
08:05:14.03 |
-04:40:19.9 |
HIP 39483 |
18.43 |
| 2026-06-07 12:00 |
08:05:16.10 |
-04:40:09.9 |
HIP 39483 |
18.96 |
| 2026-06-08 00:00 |
08:05:18.18 |
-04:40:00.1 |
HIP 39483 |
19.49 |
| 2026-06-08 12:00 |
08:05:20.28 |
-04:39:50.4 |
HIP 39483 |
20.02 |
| 2026-06-09 00:00 |
08:05:22.39 |
-04:39:40.9 |
HIP 39483 |
20.56 |
| 2026-06-09 12:00 |
08:05:24.52 |
-04:39:31.6 |
HIP 39483 |
21.10 |
| 2026-06-10 00:00 |
08:05:26.66 |
-04:39:22.4 |
HIP 39483 |
21.64 |
| 2026-06-10 12:00 |
08:05:28.82 |
-04:39:13.3 |
HIP 39483 |
22.19 |
| 2026-06-11 00:00 |
08:05:31.00 |
-04:39:04.5 |
HIP 39483 |
22.74 |
| 2026-06-11 12:00 |
08:05:33.18 |
-04:38:55.8 |
HIP 39483 |
23.29 |
| 2026-06-12 00:00 |
08:05:35.38 |
-04:38:47.3 |
HIP 39483 |
23.84 |
| 2026-06-12 12:00 |
08:05:37.60 |
-04:38:38.9 |
HIP 39483 |
24.40 |
| 2026-06-13 00:00 |
08:05:39.83 |
-04:38:30.7 |
HIP 39483 |
24.95 |
| 2026-06-13 12:00 |
08:05:42.07 |
-04:38:22.7 |
HIP 39483 |
25.52 |
| 2026-06-14 00:00 |
08:05:44.33 |
-04:38:14.8 |
HIP 39483 |
26.08 |
| 2026-06-14 12:00 |
08:05:46.60 |
-04:38:07.1 |
HIP 39483 |
26.64 |
| 2026-06-15 00:00 |
08:05:48.89 |
-04:37:59.6 |
HIP 39483 |
27.21 |
| 2026-06-15 12:00 |
08:05:51.18 |
-04:37:52.2 |
HIP 39483 |
27.78 |
| 2026-06-16 00:00 |
08:05:53.50 |
-04:37:45.0 |
HIP 39483 |
28.35 |
| 2026-06-16 12:00 |
08:05:55.82 |
-04:37:38.0 |
HIP 39483 |
28.93 |
| 2026-06-17 00:00 |
08:05:58.15 |
-04:37:31.1 |
HIP 39787 |
28.67 |
| 2026-06-17 12:00 |
08:06:00.50 |
-04:37:24.4 |
HIP 39787 |
28.08 |
| 2026-06-18 00:00 |
08:06:02.86 |
-04:37:17.9 |
HIP 39787 |
27.48 |
| 2026-06-18 12:00 |
08:06:05.24 |
-04:37:11.5 |
HIP 39787 |
26.88 |
| 2026-06-19 00:00 |
08:06:07.62 |
-04:37:05.3 |
HIP 39787 |
26.28 |
| 2026-06-19 12:00 |
08:06:10.02 |
-04:36:59.3 |
HIP 39787 |
25.67 |
| 2026-06-20 00:00 |
08:06:12.42 |
-04:36:53.5 |
HIP 39787 |
25.07 |
| 2026-06-20 12:00 |
08:06:14.84 |
-04:36:47.8 |
HIP 39787 |
24.46 |
| 2026-06-21 00:00 |
08:06:17.27 |
-04:36:42.2 |
HIP 39787 |
23.85 |
| 2026-06-21 12:00 |
08:06:19.71 |
-04:36:36.9 |
HIP 39787 |
23.23 |
| 2026-06-22 00:00 |
08:06:22.17 |
-04:36:31.7 |
HIP 39787 |
22.62 |