| Parameter |
Value |
| Designation |
C/2004 D1 (NEAT) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2006-02-10T18:19:51.231360Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:37Z |
| Obs used |
507 |
| NEO |
- |
| M1 |
8.500 |
| K1 |
8.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2005-11-18.0000000 |
| e |
1.00161667 |
| q (au) |
4.974589 |
| a (au) |
-3077.055898 |
| i (deg) |
45.537431 |
| Ω (om, deg) |
62.252904 |
| ω (w, deg) |
75.536768 |
| M (ma, deg) |
-0.000489 |
Magnitude
Scatter + Global Linear
$$
M_a = (3.833 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
3.833 |
| n |
6.000 |
| gf |
0.998 |
| gb |
-0.841 |
| k |
0.990 |
| δ90 |
9.998 |
| 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 |
17:49:49.12 |
-46:12:23.5 |
HIP 87342 |
14.04 |
| 2026-03-26 12:00 |
17:49:48.85 |
-46:12:44.5 |
HIP 87342 |
13.84 |
| 2026-03-27 00:00 |
17:49:48.55 |
-46:13:05.5 |
HIP 87342 |
13.66 |
| 2026-03-27 12:00 |
17:49:48.20 |
-46:13:26.4 |
HIP 87342 |
13.48 |
| 2026-03-28 00:00 |
17:49:47.81 |
-46:13:47.4 |
HIP 87342 |
13.32 |
| 2026-03-28 12:00 |
17:49:47.38 |
-46:14:08.3 |
HIP 87342 |
13.17 |
| 2026-03-29 00:00 |
17:49:46.92 |
-46:14:29.2 |
HIP 87342 |
13.04 |
| 2026-03-29 12:00 |
17:49:46.41 |
-46:14:50.0 |
HIP 87342 |
12.92 |
| 2026-03-30 00:00 |
17:49:45.87 |
-46:15:10.9 |
HIP 87342 |
12.81 |
| 2026-03-30 12:00 |
17:49:45.29 |
-46:15:31.7 |
HIP 87342 |
12.73 |
| 2026-03-31 00:00 |
17:49:44.66 |
-46:15:52.4 |
HIP 87342 |
12.65 |
| 2026-03-31 12:00 |
17:49:44.00 |
-46:16:13.2 |
HIP 87342 |
12.59 |
| 2026-04-01 00:00 |
17:49:43.30 |
-46:16:33.9 |
HIP 87342 |
12.55 |
| 2026-04-01 12:00 |
17:49:42.56 |
-46:16:54.5 |
HIP 87342 |
12.53 |
| 2026-04-02 00:00 |
17:49:41.78 |
-46:17:15.1 |
HIP 87342 |
12.53 |
| 2026-04-02 12:00 |
17:49:40.97 |
-46:17:35.7 |
HIP 87342 |
12.54 |
| 2026-04-03 00:00 |
17:49:40.11 |
-46:17:56.3 |
HIP 87342 |
12.57 |
| 2026-04-03 12:00 |
17:49:39.22 |
-46:18:16.8 |
HIP 87342 |
12.61 |
| 2026-04-04 00:00 |
17:49:38.28 |
-46:18:37.2 |
HIP 87342 |
12.68 |
| 2026-04-04 12:00 |
17:49:37.31 |
-46:18:57.6 |
HIP 87342 |
12.76 |
| 2026-04-05 00:00 |
17:49:36.30 |
-46:19:18.0 |
HIP 87342 |
12.86 |
| 2026-04-05 12:00 |
17:49:35.25 |
-46:19:38.3 |
HIP 87342 |
12.97 |
| 2026-04-06 00:00 |
17:49:34.16 |
-46:19:58.5 |
HIP 87342 |
13.10 |
| 2026-04-06 12:00 |
17:49:33.04 |
-46:20:18.8 |
HIP 87342 |
13.25 |
| 2026-04-07 00:00 |
17:49:31.87 |
-46:20:38.9 |
HIP 87342 |
13.42 |
| 2026-04-07 12:00 |
17:49:30.67 |
-46:20:59.0 |
HIP 87342 |
13.60 |
| 2026-04-08 00:00 |
17:49:29.43 |
-46:21:19.1 |
HIP 87342 |
13.80 |
| 2026-04-08 12:00 |
17:49:28.15 |
-46:21:39.1 |
HIP 87342 |
14.01 |
| 2026-04-09 00:00 |
17:49:26.84 |
-46:21:59.0 |
HIP 87342 |
14.23 |
| 2026-04-09 12:00 |
17:49:25.48 |
-46:22:18.9 |
HIP 87342 |
14.47 |
| 2026-04-10 00:00 |
17:49:24.09 |
-46:22:38.7 |
HIP 87133 |
14.70 |
| 2026-04-10 12:00 |
17:49:22.66 |
-46:22:58.5 |
HIP 87133 |
14.31 |
| 2026-04-11 00:00 |
17:49:21.20 |
-46:23:18.2 |
HIP 87133 |
13.93 |
| 2026-04-11 12:00 |
17:49:19.69 |
-46:23:37.8 |
HIP 87133 |
13.54 |
| 2026-04-12 00:00 |
17:49:18.15 |
-46:23:57.3 |
HIP 87133 |
13.15 |
| 2026-04-12 12:00 |
17:49:16.57 |
-46:24:16.8 |
HIP 87133 |
12.76 |
| 2026-04-13 00:00 |
17:49:14.96 |
-46:24:36.3 |
HIP 87133 |
12.36 |
| 2026-04-13 12:00 |
17:49:13.30 |
-46:24:55.6 |
HIP 87133 |
11.96 |
| 2026-04-14 00:00 |
17:49:11.61 |
-46:25:14.9 |
HIP 87133 |
11.56 |
| 2026-04-14 12:00 |
17:49:09.89 |
-46:25:34.1 |
HIP 87133 |
11.16 |
| 2026-04-15 00:00 |
17:49:08.13 |
-46:25:53.3 |
HIP 87133 |
10.75 |
| 2026-04-15 12:00 |
17:49:06.33 |
-46:26:12.3 |
HIP 87133 |
10.34 |
| 2026-04-16 00:00 |
17:49:04.49 |
-46:26:31.3 |
HIP 87133 |
9.92 |