| Parameter |
Value |
| Designation |
189P/NEAT |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2007-07-25T22:31:20.040960Z |
| Orbit solution date (soln_date, UTC) |
2022-08-26T23:43:11Z |
| Obs used |
1469 |
| NEO |
Yes |
| M1 |
19.100 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2008-12-04.0000000 |
| e |
0.59764285 |
| q (au) |
1.173925 |
| a (au) |
2.917619 |
| i (deg) |
20.400629 |
| Ω (om, deg) |
282.200061 |
| ω (w, deg) |
15.307418 |
| M (ma, deg) |
98.304051 |
Magnitude
Scatter + Global Linear
$$
M_a = (19.737 + 2.780\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
19.737 |
| n |
2.780 |
| gf |
1.000 |
| gb |
-0.866 |
| k |
0.800 |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
09:41:39.47 |
+00:10:29.6 |
HIP 47604 |
29.39 |
| 2026-07-29 12:00 |
09:42:10.88 |
+00:07:44.0 |
HIP 47604 |
24.70 |
| 2026-07-30 00:00 |
09:42:42.35 |
+00:04:57.3 |
HIP 47604 |
22.24 |
| 2026-07-30 12:00 |
09:43:13.87 |
+00:02:09.7 |
HIP 47604 |
22.75 |
| 2026-07-31 00:00 |
09:43:45.44 |
-00:00:39.0 |
HIP 47604 |
26.09 |
| 2026-07-31 12:00 |
09:44:17.07 |
-00:03:28.7 |
HIP 47849 |
27.94 |
| 2026-08-01 00:00 |
09:44:48.75 |
-00:06:19.3 |
HIP 47948 |
22.11 |
| 2026-08-01 12:00 |
09:45:20.49 |
-00:09:11.0 |
HIP 47948 |
16.11 |
| 2026-08-02 00:00 |
09:45:52.27 |
-00:12:03.6 |
HIP 47948 |
13.14 |
| 2026-08-02 12:00 |
09:46:24.11 |
-00:14:57.2 |
HIP 47948 |
15.13 |
| 2026-08-03 00:00 |
09:46:55.99 |
-00:17:51.9 |
HIP 48000 |
19.38 |
| 2026-08-03 12:00 |
09:47:27.93 |
-00:20:47.5 |
HIP 48000 |
17.31 |
| 2026-08-04 00:00 |
09:47:59.92 |
-00:23:44.1 |
HIP 48000 |
19.19 |
| 2026-08-04 12:00 |
09:48:31.96 |
-00:26:41.7 |
HIP 48118 |
21.95 |
| 2026-08-05 00:00 |
09:49:04.05 |
-00:29:40.3 |
HIP 48118 |
20.21 |
| 2026-08-05 12:00 |
09:49:36.19 |
-00:32:39.9 |
HIP 48252 |
20.99 |
| 2026-08-06 00:00 |
09:50:08.38 |
-00:35:40.5 |
HIP 48252 |
21.99 |
| 2026-08-06 12:00 |
09:50:40.61 |
-00:38:42.1 |
HIP 48252 |
25.98 |
| 2026-08-07 00:00 |
09:51:12.89 |
-00:41:44.6 |
HIP 48252 |
31.88 |
| 2026-08-07 12:00 |
09:51:45.23 |
-00:44:48.1 |
HIP 48252 |
38.82 |
| 2026-08-08 00:00 |
09:52:17.60 |
-00:47:52.7 |
HIP 48590 |
41.51 |
| 2026-08-08 12:00 |
09:52:50.03 |
-00:50:58.2 |
HIP 48582 |
35.63 |
| 2026-08-09 00:00 |
09:53:22.50 |
-00:54:04.7 |
HIP 48582 |
27.93 |
| 2026-08-09 12:00 |
09:53:55.01 |
-00:57:12.1 |
HIP 48582 |
21.00 |
| 2026-08-10 00:00 |
09:54:27.58 |
-01:00:20.6 |
HIP 48582 |
15.92 |
| 2026-08-10 12:00 |
09:55:00.18 |
-01:03:30.0 |
HIP 48671 |
9.64 |
| 2026-08-11 00:00 |
09:55:32.83 |
-01:06:40.4 |
HIP 48671 |
1.06 |
| 2026-08-11 12:00 |
09:56:05.52 |
-01:09:51.8 |
HIP 48671 |
7.93 |
| 2026-08-12 00:00 |
09:56:38.26 |
-01:13:04.1 |
HIP 48671 |
16.71 |
| 2026-08-12 12:00 |
09:57:11.04 |
-01:16:17.4 |
HIP 48671 |
25.51 |
| 2026-08-13 00:00 |
09:57:43.86 |
-01:19:31.7 |
HIP 48671 |
34.32 |
| 2026-08-13 12:00 |
09:58:16.72 |
-01:22:47.0 |
HIP 48839 |
34.71 |
| 2026-08-14 00:00 |
09:58:49.62 |
-01:26:03.2 |
HIP 49037 |
31.55 |
| 2026-08-14 12:00 |
09:59:22.56 |
-01:29:20.3 |
HIP 49037 |
29.33 |
| 2026-08-15 00:00 |
09:59:55.54 |
-01:32:38.4 |
HIP 49037 |
29.72 |
| 2026-08-15 12:00 |
10:00:28.56 |
-01:35:57.5 |
HIP 49037 |
32.64 |
| 2026-08-16 00:00 |
10:01:01.61 |
-01:39:17.5 |
HIP 49037 |
37.51 |
| 2026-08-16 12:00 |
10:01:34.71 |
-01:42:38.4 |
HIP 49151 |
33.90 |
| 2026-08-17 00:00 |
10:02:07.84 |
-01:46:00.3 |
HIP 49151 |
30.51 |
| 2026-08-17 12:00 |
10:02:41.01 |
-01:49:23.2 |
HIP 49335 |
25.14 |
| 2026-08-18 00:00 |
10:03:14.21 |
-01:52:47.0 |
HIP 49335 |
19.21 |
| 2026-08-18 12:00 |
10:03:47.45 |
-01:56:11.7 |
HIP 49335 |
16.35 |
| 2026-08-19 00:00 |
10:04:20.73 |
-01:59:37.3 |
HIP 49335 |
18.09 |