| Parameter |
Value |
| Designation |
C/2002 J4 (NEAT) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2003-10-03T04:21:57.335040Z |
| Orbit solution date (soln_date, UTC) |
2025-07-31T12:12:21Z |
| Obs used |
228 |
| NEO |
- |
| M1 |
10.900 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2003-04-06.0000000 |
| e |
0.99989069 |
| q (au) |
3.633732 |
| a (au) |
33243.727305 |
| i (deg) |
46.525144 |
| Ω (om, deg) |
70.884245 |
| ω (w, deg) |
230.709337 |
| M (ma, deg) |
359.999971 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.255 + 3.626\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.255 |
| n |
3.626 |
| gf |
0.983 |
| gb |
-0.894 |
| k |
0.999 |
| δ90 |
9.909 |
| 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) |
| 2026-07-29 00:00 |
05:27:58.75 |
+34:52:54.1 |
HIP 25565 |
6.07 |
| 2026-07-29 12:00 |
05:28:01.30 |
+34:53:03.5 |
HIP 25565 |
6.35 |
| 2026-07-30 00:00 |
05:28:03.82 |
+34:53:12.8 |
HIP 25565 |
6.67 |
| 2026-07-30 12:00 |
05:28:06.32 |
+34:53:22.2 |
HIP 25565 |
7.01 |
| 2026-07-31 00:00 |
05:28:08.80 |
+34:53:31.6 |
HIP 25565 |
7.37 |
| 2026-07-31 12:00 |
05:28:11.27 |
+34:53:41.1 |
HIP 25565 |
7.75 |
| 2026-08-01 00:00 |
05:28:13.71 |
+34:53:50.6 |
HIP 25565 |
8.15 |
| 2026-08-01 12:00 |
05:28:16.14 |
+34:54:00.1 |
HIP 25565 |
8.55 |
| 2026-08-02 00:00 |
05:28:18.55 |
+34:54:09.7 |
HIP 25565 |
8.97 |
| 2026-08-02 12:00 |
05:28:20.94 |
+34:54:19.3 |
HIP 25565 |
9.40 |
| 2026-08-03 00:00 |
05:28:23.30 |
+34:54:28.9 |
HIP 25565 |
9.83 |
| 2026-08-03 12:00 |
05:28:25.65 |
+34:54:38.6 |
HIP 25565 |
10.27 |
| 2026-08-04 00:00 |
05:28:27.98 |
+34:54:48.3 |
HIP 25565 |
10.71 |
| 2026-08-04 12:00 |
05:28:30.28 |
+34:54:58.0 |
HIP 25565 |
11.15 |
| 2026-08-05 00:00 |
05:28:32.57 |
+34:55:07.8 |
HIP 25565 |
11.60 |
| 2026-08-05 12:00 |
05:28:34.84 |
+34:55:17.5 |
HIP 25565 |
12.04 |
| 2026-08-06 00:00 |
05:28:37.08 |
+34:55:27.4 |
HIP 25565 |
12.49 |
| 2026-08-06 12:00 |
05:28:39.30 |
+34:55:37.2 |
HIP 25565 |
12.94 |
| 2026-08-07 00:00 |
05:28:41.51 |
+34:55:47.1 |
HIP 25565 |
13.39 |
| 2026-08-07 12:00 |
05:28:43.69 |
+34:55:57.0 |
HIP 25565 |
13.83 |
| 2026-08-08 00:00 |
05:28:45.85 |
+34:56:07.0 |
HIP 25565 |
14.28 |
| 2026-08-08 12:00 |
05:28:47.98 |
+34:56:16.9 |
HIP 25565 |
14.72 |
| 2026-08-09 00:00 |
05:28:50.10 |
+34:56:26.9 |
HIP 25735 |
14.89 |
| 2026-08-09 12:00 |
05:28:52.19 |
+34:56:36.9 |
HIP 25735 |
14.46 |
| 2026-08-10 00:00 |
05:28:54.27 |
+34:56:47.0 |
HIP 25735 |
14.04 |
| 2026-08-10 12:00 |
05:28:56.32 |
+34:56:57.1 |
HIP 25735 |
13.62 |
| 2026-08-11 00:00 |
05:28:58.34 |
+34:57:07.2 |
HIP 25735 |
13.21 |
| 2026-08-11 12:00 |
05:29:00.35 |
+34:57:17.3 |
HIP 25735 |
12.80 |
| 2026-08-12 00:00 |
05:29:02.33 |
+34:57:27.5 |
HIP 25735 |
12.40 |
| 2026-08-12 12:00 |
05:29:04.29 |
+34:57:37.7 |
HIP 25735 |
12.00 |
| 2026-08-13 00:00 |
05:29:06.22 |
+34:57:47.9 |
HIP 25735 |
11.61 |
| 2026-08-13 12:00 |
05:29:08.13 |
+34:57:58.1 |
HIP 25735 |
11.23 |
| 2026-08-14 00:00 |
05:29:10.02 |
+34:58:08.4 |
HIP 25735 |
10.85 |
| 2026-08-14 12:00 |
05:29:11.88 |
+34:58:18.6 |
HIP 25735 |
10.48 |
| 2026-08-15 00:00 |
05:29:13.72 |
+34:58:28.9 |
HIP 25735 |
10.11 |
| 2026-08-15 12:00 |
05:29:15.54 |
+34:58:39.3 |
HIP 25735 |
9.75 |
| 2026-08-16 00:00 |
05:29:17.33 |
+34:58:49.6 |
HIP 25735 |
9.40 |
| 2026-08-16 12:00 |
05:29:19.10 |
+34:59:00.0 |
HIP 25735 |
9.05 |
| 2026-08-17 00:00 |
05:29:20.85 |
+34:59:10.3 |
HIP 25735 |
8.71 |
| 2026-08-17 12:00 |
05:29:22.57 |
+34:59:20.7 |
HIP 25735 |
8.38 |
| 2026-08-18 00:00 |
05:29:24.26 |
+34:59:31.2 |
HIP 25735 |
8.05 |
| 2026-08-18 12:00 |
05:29:25.93 |
+34:59:41.6 |
HIP 25735 |
7.73 |
| 2026-08-19 00:00 |
05:29:27.58 |
+34:59:52.1 |
HIP 25735 |
7.43 |