42P/Neujmin 3
| 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) |
| 2026-02-03 00:00 |
20:41:13.82 |
-17:07:44.1 |
HIP 102178 |
14.46 |
| 2026-02-03 12:00 |
20:42:29.11 |
-17:03:28.7 |
HIP 102178 |
4.04 |
| 2026-02-04 00:00 |
20:43:44.32 |
-16:59:11.5 |
HIP 102178 |
22.51 |
| 2026-02-04 12:00 |
20:44:59.44 |
-16:54:52.7 |
HIP 102515 |
25.51 |
| 2026-02-05 00:00 |
20:46:14.47 |
-16:50:32.2 |
HIP 102515 |
9.54 |
| 2026-02-05 12:00 |
20:47:29.40 |
-16:46:10.1 |
HIP 102600 |
2.51 |
| 2026-02-06 00:00 |
20:48:44.25 |
-16:41:46.3 |
HIP 102659 |
7.87 |
| 2026-02-06 12:00 |
20:49:59.00 |
-16:37:20.8 |
HIP 102922 |
20.29 |
| 2026-02-07 00:00 |
20:51:13.67 |
-16:32:53.8 |
HIP 102922 |
8.24 |
| 2026-02-07 12:00 |
20:52:28.24 |
-16:28:25.1 |
HIP 103059 |
19.21 |
| 2026-02-08 00:00 |
20:53:42.71 |
-16:23:54.9 |
HIP 103059 |
18.93 |
| 2026-02-08 12:00 |
20:54:57.10 |
-16:19:23.1 |
HIP 103059 |
32.03 |
| 2026-02-09 00:00 |
20:56:11.38 |
-16:14:49.7 |
HIP 103460 |
25.03 |
| 2026-02-09 12:00 |
20:57:25.57 |
-16:10:14.8 |
HIP 103460 |
9.10 |
| 2026-02-10 00:00 |
20:58:39.67 |
-16:05:38.3 |
HIP 103576 |
6.48 |
| 2026-02-10 12:00 |
20:59:53.67 |
-16:01:00.4 |
HIP 103576 |
12.19 |
| 2026-02-11 00:00 |
21:01:07.57 |
-15:56:20.9 |
HIP 103697 |
8.19 |
| 2026-02-11 12:00 |
21:02:21.37 |
-15:51:40.0 |
HIP 103697 |
22.94 |
| 2026-02-12 00:00 |
21:03:35.08 |
-15:46:57.6 |
HIP 103847 |
23.61 |
| 2026-02-12 12:00 |
21:04:48.68 |
-15:42:13.8 |
HIP 104161 |
20.45 |
| 2026-02-13 00:00 |
21:06:02.18 |
-15:37:28.5 |
HIP 104161 |
6.49 |
| 2026-02-13 12:00 |
21:07:15.59 |
-15:32:41.8 |
HIP 104321 |
11.32 |
| 2026-02-14 00:00 |
21:08:28.89 |
-15:27:53.8 |
HIP 104321 |
12.04 |
| 2026-02-14 12:00 |
21:09:42.08 |
-15:23:04.3 |
HIP 104505 |
20.13 |
| 2026-02-15 00:00 |
21:10:55.18 |
-15:18:13.5 |
HIP 104505 |
26.54 |
| 2026-02-15 12:00 |
21:12:08.17 |
-15:13:21.3 |
HIP 104687 |
13.80 |
| 2026-02-16 00:00 |
21:13:21.06 |
-15:08:27.9 |
HIP 104687 |
16.46 |
| 2026-02-16 12:00 |
21:14:33.84 |
-15:03:33.1 |
HIP 104918 |
9.60 |
| 2026-02-17 00:00 |
21:15:46.52 |
-14:58:37.0 |
HIP 104974 |
11.68 |
| 2026-02-17 12:00 |
21:16:59.09 |
-14:53:39.6 |
HIP 105042 |
7.04 |
| 2026-02-18 00:00 |
21:18:11.55 |
-14:48:41.0 |
HIP 105042 |
23.13 |
| 2026-02-18 12:00 |
21:19:23.91 |
-14:43:41.1 |
HIP 105287 |
20.78 |
| 2026-02-19 00:00 |
21:20:36.15 |
-14:38:40.1 |
HIP 105287 |
21.77 |
| 2026-02-19 12:00 |
21:21:48.29 |
-14:33:37.8 |
HIP 105519 |
22.60 |
| 2026-02-20 00:00 |
21:23:00.32 |
-14:28:34.3 |
HIP 105519 |
28.64 |
| 2026-02-20 12:00 |
21:24:12.24 |
-14:23:29.7 |
HIP 105782 |
18.89 |
| 2026-02-21 00:00 |
21:25:24.05 |
-14:18:23.9 |
HIP 105782 |
1.77 |
| 2026-02-21 12:00 |
21:26:35.74 |
-14:13:17.0 |
HIP 105782 |
17.49 |
| 2026-02-22 00:00 |
21:27:47.33 |
-14:08:08.9 |
HIP 106068 |
27.54 |
| 2026-02-22 12:00 |
21:28:58.80 |
-14:02:59.8 |
HIP 106115 |
10.12 |
| 2026-02-23 00:00 |
21:30:10.16 |
-13:57:49.6 |
HIP 106115 |
8.20 |
| 2026-02-23 12:00 |
21:31:21.40 |
-13:52:38.3 |
HIP 106115 |
26.15 |
| 2026-02-24 00:00 |
21:32:32.54 |
-13:47:26.0 |
HIP 106380 |
20.20 |