| Parameter |
Value |
| Designation |
166P/NEAT |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2002-05-20T20:10:57.889920Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:27:43Z |
| Obs used |
168 |
| NEO |
- |
| M1 |
7.000 |
| K1 |
8.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2003-06-29.0000000 |
| e |
0.38310092 |
| q (au) |
8.564302 |
| a (au) |
13.882826 |
| i (deg) |
15.368401 |
| Ω (om, deg) |
64.488838 |
| ω (w, deg) |
321.878902 |
| M (ma, deg) |
7.700866 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.234 + 3.388\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.234 |
| n |
3.388 |
| gf |
0.964 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
9.999 |
| 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) |
| 2026-03-26 00:00 |
13:36:44.64 |
+02:04:32.7 |
HIP 66399 |
11.47 |
| 2026-03-26 12:00 |
13:36:39.96 |
+02:05:03.0 |
HIP 66399 |
12.12 |
| 2026-03-27 00:00 |
13:36:35.26 |
+02:05:33.3 |
HIP 66399 |
12.87 |
| 2026-03-27 12:00 |
13:36:30.54 |
+02:06:03.6 |
HIP 66399 |
13.69 |
| 2026-03-28 00:00 |
13:36:25.81 |
+02:06:33.8 |
HIP 66399 |
14.59 |
| 2026-03-28 12:00 |
13:36:21.05 |
+02:07:03.9 |
HIP 66399 |
15.54 |
| 2026-03-29 00:00 |
13:36:16.28 |
+02:07:34.0 |
HIP 66399 |
16.53 |
| 2026-03-29 12:00 |
13:36:11.49 |
+02:08:03.9 |
HIP 66399 |
17.57 |
| 2026-03-30 00:00 |
13:36:06.69 |
+02:08:33.8 |
HIP 66399 |
18.64 |
| 2026-03-30 12:00 |
13:36:01.87 |
+02:09:03.7 |
HIP 66399 |
19.74 |
| 2026-03-31 00:00 |
13:35:57.03 |
+02:09:33.4 |
HIP 66399 |
20.86 |
| 2026-03-31 12:00 |
13:35:52.18 |
+02:10:03.1 |
HIP 66399 |
22.00 |
| 2026-04-01 00:00 |
13:35:47.31 |
+02:10:32.7 |
HIP 66399 |
23.17 |
| 2026-04-01 12:00 |
13:35:42.43 |
+02:11:02.2 |
HIP 66399 |
24.35 |
| 2026-04-02 00:00 |
13:35:37.54 |
+02:11:31.5 |
HIP 66399 |
25.54 |
| 2026-04-02 12:00 |
13:35:32.63 |
+02:12:00.8 |
HIP 66399 |
26.75 |
| 2026-04-03 00:00 |
13:35:27.71 |
+02:12:30.0 |
HIP 66399 |
27.97 |
| 2026-04-03 12:00 |
13:35:22.77 |
+02:12:59.1 |
HIP 66349 |
29.05 |
| 2026-04-04 00:00 |
13:35:17.83 |
+02:13:28.1 |
HIP 66349 |
28.96 |
| 2026-04-04 12:00 |
13:35:12.87 |
+02:13:57.0 |
HIP 66349 |
28.93 |
| 2026-04-05 00:00 |
13:35:07.90 |
+02:14:25.8 |
HIP 66349 |
28.96 |
| 2026-04-05 12:00 |
13:35:02.93 |
+02:14:54.4 |
HIP 66349 |
29.06 |
| 2026-04-06 00:00 |
13:34:57.94 |
+02:15:23.0 |
HIP 66349 |
29.22 |
| 2026-04-06 12:00 |
13:34:52.94 |
+02:15:51.4 |
HIP 66349 |
29.44 |
| 2026-04-07 00:00 |
13:34:47.93 |
+02:16:19.7 |
HIP 66349 |
29.73 |
| 2026-04-07 12:00 |
13:34:42.92 |
+02:16:47.9 |
HIP 66349 |
30.07 |
| 2026-04-08 00:00 |
13:34:37.90 |
+02:17:15.9 |
HIP 66349 |
30.47 |
| 2026-04-08 12:00 |
13:34:32.86 |
+02:17:43.8 |
HIP 66349 |
30.93 |
| 2026-04-09 00:00 |
13:34:27.83 |
+02:18:11.6 |
HIP 66071 |
30.11 |
| 2026-04-09 12:00 |
13:34:22.78 |
+02:18:39.2 |
HIP 66071 |
29.24 |
| 2026-04-10 00:00 |
13:34:17.73 |
+02:19:06.7 |
HIP 66071 |
28.39 |
| 2026-04-10 12:00 |
13:34:12.68 |
+02:19:34.0 |
HIP 66071 |
27.59 |
| 2026-04-11 00:00 |
13:34:07.61 |
+02:20:01.2 |
HIP 66071 |
26.83 |
| 2026-04-11 12:00 |
13:34:02.55 |
+02:20:28.3 |
HIP 66071 |
26.11 |
| 2026-04-12 00:00 |
13:33:57.48 |
+02:20:55.1 |
HIP 66071 |
25.44 |
| 2026-04-12 12:00 |
13:33:52.40 |
+02:21:21.9 |
HIP 66071 |
24.82 |
| 2026-04-13 00:00 |
13:33:47.33 |
+02:21:48.4 |
HIP 66071 |
24.26 |
| 2026-04-13 12:00 |
13:33:42.25 |
+02:22:14.9 |
HIP 66071 |
23.76 |
| 2026-04-14 00:00 |
13:33:37.17 |
+02:22:41.1 |
HIP 66071 |
23.33 |
| 2026-04-14 12:00 |
13:33:32.09 |
+02:23:07.2 |
HIP 66071 |
22.96 |
| 2026-04-15 00:00 |
13:33:27.00 |
+02:23:33.1 |
HIP 66071 |
22.66 |
| 2026-04-15 12:00 |
13:33:21.92 |
+02:23:58.8 |
HIP 66071 |
22.43 |
| 2026-04-16 00:00 |
13:33:16.84 |
+02:24:24.3 |
HIP 66071 |
22.29 |