| 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) |
| 2026-05-12 00:00 |
17:46:43.91 |
-46:40:39.5 |
HIP 87133 |
18.24 |
| 2026-05-12 12:00 |
17:46:40.44 |
-46:40:52.6 |
HIP 87133 |
18.86 |
| 2026-05-13 00:00 |
17:46:36.95 |
-46:41:05.6 |
HIP 86857 |
19.46 |
| 2026-05-13 12:00 |
17:46:33.44 |
-46:41:18.4 |
HIP 86857 |
18.83 |
| 2026-05-14 00:00 |
17:46:29.90 |
-46:41:31.0 |
HIP 86857 |
18.19 |
| 2026-05-14 12:00 |
17:46:26.34 |
-46:41:43.6 |
HIP 86857 |
17.55 |
| 2026-05-15 00:00 |
17:46:22.76 |
-46:41:55.9 |
HIP 86857 |
16.90 |
| 2026-05-15 12:00 |
17:46:19.15 |
-46:42:08.2 |
HIP 86857 |
16.26 |
| 2026-05-16 00:00 |
17:46:15.53 |
-46:42:20.2 |
HIP 86857 |
15.60 |
| 2026-05-16 12:00 |
17:46:11.88 |
-46:42:32.2 |
HIP 86857 |
14.95 |
| 2026-05-17 00:00 |
17:46:08.20 |
-46:42:44.0 |
HIP 86857 |
14.30 |
| 2026-05-17 12:00 |
17:46:04.51 |
-46:42:55.6 |
HIP 86857 |
13.64 |
| 2026-05-18 00:00 |
17:46:00.80 |
-46:43:07.1 |
HIP 86857 |
12.97 |
| 2026-05-18 12:00 |
17:45:57.06 |
-46:43:18.4 |
HIP 86857 |
12.31 |
| 2026-05-19 00:00 |
17:45:53.30 |
-46:43:29.6 |
HIP 86857 |
11.64 |
| 2026-05-19 12:00 |
17:45:49.53 |
-46:43:40.6 |
HIP 86857 |
10.97 |
| 2026-05-20 00:00 |
17:45:45.73 |
-46:43:51.5 |
HIP 86857 |
10.30 |
| 2026-05-20 12:00 |
17:45:41.92 |
-46:44:02.2 |
HIP 86857 |
9.63 |
| 2026-05-21 00:00 |
17:45:38.08 |
-46:44:12.8 |
HIP 86857 |
8.95 |
| 2026-05-21 12:00 |
17:45:34.23 |
-46:44:23.2 |
HIP 86857 |
8.27 |
| 2026-05-22 00:00 |
17:45:30.36 |
-46:44:33.5 |
HIP 86857 |
7.59 |
| 2026-05-22 12:00 |
17:45:26.47 |
-46:44:43.6 |
HIP 86857 |
6.91 |
| 2026-05-23 00:00 |
17:45:22.56 |
-46:44:53.5 |
HIP 86857 |
6.23 |
| 2026-05-23 12:00 |
17:45:18.64 |
-46:45:03.3 |
HIP 86857 |
5.54 |
| 2026-05-24 00:00 |
17:45:14.69 |
-46:45:12.9 |
HIP 86857 |
4.86 |
| 2026-05-24 12:00 |
17:45:10.74 |
-46:45:22.4 |
HIP 86857 |
4.17 |
| 2026-05-25 00:00 |
17:45:06.76 |
-46:45:31.7 |
HIP 86857 |
3.48 |
| 2026-05-25 12:00 |
17:45:02.77 |
-46:45:40.8 |
HIP 86857 |
2.80 |
| 2026-05-26 00:00 |
17:44:58.77 |
-46:45:49.8 |
HIP 86857 |
2.13 |
| 2026-05-26 12:00 |
17:44:54.74 |
-46:45:58.7 |
HIP 86857 |
1.49 |
| 2026-05-27 00:00 |
17:44:50.71 |
-46:46:07.3 |
HIP 86857 |
0.93 |
| 2026-05-27 12:00 |
17:44:46.66 |
-46:46:15.8 |
HIP 86857 |
0.71 |
| 2026-05-28 00:00 |
17:44:42.59 |
-46:46:24.2 |
HIP 86857 |
1.07 |
| 2026-05-28 12:00 |
17:44:38.51 |
-46:46:32.3 |
HIP 86857 |
1.67 |
| 2026-05-29 00:00 |
17:44:34.42 |
-46:46:40.3 |
HIP 86857 |
2.34 |
| 2026-05-29 12:00 |
17:44:30.31 |
-46:46:48.2 |
HIP 86857 |
3.03 |
| 2026-05-30 00:00 |
17:44:26.19 |
-46:46:55.9 |
HIP 86857 |
3.73 |
| 2026-05-30 12:00 |
17:44:22.06 |
-46:47:03.4 |
HIP 86857 |
4.43 |
| 2026-05-31 00:00 |
17:44:17.91 |
-46:47:10.7 |
HIP 86857 |
5.14 |
| 2026-05-31 12:00 |
17:44:13.76 |
-46:47:17.9 |
HIP 86857 |
5.86 |
| 2026-06-01 00:00 |
17:44:09.59 |
-46:47:24.9 |
HIP 86857 |
6.57 |
| 2026-06-01 12:00 |
17:44:05.41 |
-46:47:31.8 |
HIP 86857 |
7.29 |
| 2026-06-02 00:00 |
17:44:01.22 |
-46:47:38.5 |
HIP 86857 |
8.01 |