| Parameter |
Value |
| Designation |
42P/Neujmin 3 |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2004-07-16T05:22:50.543040Z |
| Orbit solution date (soln_date, UTC) |
2025-05-16T08:56:55Z |
| Obs used |
262 |
| NEO |
- |
| M1 |
16.600 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2007-01-20.0000000 |
| e |
0.58562308 |
| q (au) |
2.013138 |
| a (au) |
4.858229 |
| i (deg) |
3.985667 |
| Ω (om, deg) |
150.351892 |
| ω (w, deg) |
147.175572 |
| M (ma, deg) |
84.474127 |
Magnitude
Scatter + Global Linear
$$
M_a = (17.715 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
17.715 |
| n |
6.000 |
| gf |
0.915 |
| gb |
-0.848 |
| k |
0.839 |
| δ90 |
5.975 |
| 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) |
| 2026-03-26 00:00 |
22:40:06.41 |
-08:13:18.4 |
HIP 111761 |
32.33 |
| 2026-03-26 12:00 |
22:41:10.29 |
-08:07:32.7 |
HIP 112168 |
30.12 |
| 2026-03-27 00:00 |
22:42:14.05 |
-08:01:46.9 |
HIP 112168 |
20.85 |
| 2026-03-27 12:00 |
22:43:17.68 |
-07:56:01.1 |
HIP 112168 |
22.94 |
| 2026-03-28 00:00 |
22:44:21.19 |
-07:50:15.3 |
HIP 112283 |
13.70 |
| 2026-03-28 12:00 |
22:45:24.58 |
-07:44:29.5 |
HIP 112283 |
14.22 |
| 2026-03-29 00:00 |
22:46:27.84 |
-07:38:43.6 |
HIP 112514 |
19.29 |
| 2026-03-29 12:00 |
22:47:30.98 |
-07:32:57.8 |
HIP 112514 |
6.95 |
| 2026-03-30 00:00 |
22:48:33.99 |
-07:27:12.1 |
HIP 112514 |
16.72 |
| 2026-03-30 12:00 |
22:49:36.88 |
-07:21:26.3 |
HIP 112769 |
11.11 |
| 2026-03-31 00:00 |
22:50:39.65 |
-07:15:40.7 |
HIP 112813 |
3.46 |
| 2026-03-31 12:00 |
22:51:42.30 |
-07:09:55.1 |
HIP 112813 |
16.44 |
| 2026-04-01 00:00 |
22:52:44.82 |
-07:04:09.5 |
HIP 113059 |
24.56 |
| 2026-04-01 12:00 |
22:53:47.22 |
-06:58:24.1 |
HIP 113150 |
14.72 |
| 2026-04-02 00:00 |
22:54:49.49 |
-06:52:38.8 |
HIP 113150 |
5.25 |
| 2026-04-02 12:00 |
22:55:51.64 |
-06:46:53.6 |
HIP 113279 |
15.85 |
| 2026-04-03 00:00 |
22:56:53.67 |
-06:41:08.5 |
HIP 113329 |
8.25 |
| 2026-04-03 12:00 |
22:57:55.58 |
-06:35:23.6 |
HIP 113379 |
2.97 |
| 2026-04-04 00:00 |
22:58:57.37 |
-06:29:38.8 |
HIP 113522 |
10.42 |
| 2026-04-04 12:00 |
22:59:59.03 |
-06:23:54.2 |
HIP 113522 |
14.58 |
| 2026-04-05 00:00 |
23:01:00.57 |
-06:18:09.8 |
HIP 113723 |
24.21 |
| 2026-04-05 12:00 |
23:02:01.98 |
-06:12:25.6 |
HIP 113723 |
14.58 |
| 2026-04-06 00:00 |
23:03:03.27 |
-06:06:41.6 |
HIP 113723 |
19.24 |
| 2026-04-06 12:00 |
23:04:04.45 |
-06:00:57.8 |
HIP 113926 |
14.72 |
| 2026-04-07 00:00 |
23:05:05.49 |
-05:55:14.3 |
HIP 113926 |
15.68 |
| 2026-04-07 12:00 |
23:06:06.42 |
-05:49:31.0 |
HIP 114218 |
27.04 |
| 2026-04-08 00:00 |
23:07:07.22 |
-05:43:48.0 |
HIP 114218 |
10.99 |
| 2026-04-08 12:00 |
23:08:07.90 |
-05:38:05.3 |
HIP 114218 |
5.70 |
| 2026-04-09 00:00 |
23:09:08.45 |
-05:32:22.8 |
HIP 114310 |
11.99 |
| 2026-04-09 12:00 |
23:10:08.88 |
-05:26:40.7 |
HIP 114310 |
17.86 |
| 2026-04-10 00:00 |
23:11:09.19 |
-05:20:58.8 |
HIP 114493 |
15.18 |
| 2026-04-10 12:00 |
23:12:09.38 |
-05:15:17.3 |
HIP 114493 |
16.02 |
| 2026-04-11 00:00 |
23:13:09.44 |
-05:09:36.2 |
HIP 114677 |
22.81 |
| 2026-04-11 12:00 |
23:14:09.38 |
-05:03:55.4 |
HIP 114677 |
15.10 |
| 2026-04-12 00:00 |
23:15:09.19 |
-04:58:14.9 |
HIP 114677 |
21.08 |
| 2026-04-12 12:00 |
23:16:08.88 |
-04:52:34.9 |
HIP 114803 |
23.87 |
| 2026-04-13 00:00 |
23:17:08.44 |
-04:46:55.3 |
HIP 115030 |
19.26 |
| 2026-04-13 12:00 |
23:18:07.88 |
-04:41:16.0 |
HIP 115030 |
10.56 |
| 2026-04-14 00:00 |
23:19:07.20 |
-04:35:37.2 |
HIP 115030 |
18.81 |
| 2026-04-14 12:00 |
23:20:06.38 |
-04:29:58.9 |
HIP 115316 |
21.42 |
| 2026-04-15 00:00 |
23:21:05.45 |
-04:24:20.9 |
HIP 115316 |
16.51 |
| 2026-04-15 12:00 |
23:22:04.39 |
-04:18:43.5 |
HIP 115414 |
10.29 |
| 2026-04-16 00:00 |
23:23:03.20 |
-04:13:06.5 |
HIP 115414 |
9.04 |