| 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
$$
M_a = (17.697 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
17.697 |
| n |
6.000 |
| gf |
0.806 |
| gb |
-0.848 |
| k |
0.840 |
| δ90 |
5.639 |
| 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) |
| 2026-07-29 00:00 |
01:49:48.47 |
+08:26:30.7 |
HIP 8612 |
20.41 |
| 2026-07-29 12:00 |
01:50:07.85 |
+08:27:21.7 |
HIP 8612 |
15.61 |
| 2026-07-30 00:00 |
01:50:26.92 |
+08:28:10.7 |
HIP 8612 |
10.95 |
| 2026-07-30 12:00 |
01:50:45.68 |
+08:28:57.8 |
HIP 8612 |
6.56 |
| 2026-07-31 00:00 |
01:51:04.13 |
+08:29:43.0 |
HIP 8612 |
3.27 |
| 2026-07-31 12:00 |
01:51:22.26 |
+08:30:26.2 |
HIP 8612 |
4.54 |
| 2026-08-01 00:00 |
01:51:40.07 |
+08:31:07.4 |
HIP 8612 |
8.40 |
| 2026-08-01 12:00 |
01:51:57.57 |
+08:31:46.7 |
HIP 8612 |
12.59 |
| 2026-08-02 00:00 |
01:52:14.74 |
+08:32:24.0 |
HIP 8612 |
16.79 |
| 2026-08-02 12:00 |
01:52:31.60 |
+08:32:59.3 |
HIP 8612 |
20.95 |
| 2026-08-03 00:00 |
01:52:48.13 |
+08:33:32.7 |
HIP 8612 |
25.04 |
| 2026-08-03 12:00 |
01:53:04.34 |
+08:34:04.0 |
HIP 8883 |
23.10 |
| 2026-08-04 00:00 |
01:53:20.22 |
+08:34:33.4 |
HIP 8883 |
19.64 |
| 2026-08-04 12:00 |
01:53:35.77 |
+08:35:00.8 |
HIP 8883 |
16.48 |
| 2026-08-05 00:00 |
01:53:51.00 |
+08:35:26.2 |
HIP 8883 |
13.78 |
| 2026-08-05 12:00 |
01:54:05.89 |
+08:35:49.6 |
HIP 8883 |
11.74 |
| 2026-08-06 00:00 |
01:54:20.45 |
+08:36:11.0 |
HIP 8883 |
10.69 |
| 2026-08-06 12:00 |
01:54:34.68 |
+08:36:30.4 |
HIP 8883 |
10.81 |
| 2026-08-07 00:00 |
01:54:48.57 |
+08:36:47.8 |
HIP 8883 |
12.00 |
| 2026-08-07 12:00 |
01:55:02.13 |
+08:37:03.2 |
HIP 8883 |
13.92 |
| 2026-08-08 00:00 |
01:55:15.34 |
+08:37:16.5 |
HIP 8883 |
16.27 |
| 2026-08-08 12:00 |
01:55:28.22 |
+08:37:27.9 |
HIP 9035 |
15.07 |
| 2026-08-09 00:00 |
01:55:40.75 |
+08:37:37.2 |
HIP 9035 |
12.48 |
| 2026-08-09 12:00 |
01:55:52.94 |
+08:37:44.5 |
HIP 9035 |
10.22 |
| 2026-08-10 00:00 |
01:56:04.79 |
+08:37:49.8 |
HIP 9035 |
8.46 |
| 2026-08-10 12:00 |
01:56:16.28 |
+08:37:53.1 |
HIP 9035 |
7.46 |
| 2026-08-11 00:00 |
01:56:27.43 |
+08:37:54.3 |
HIP 9035 |
7.43 |
| 2026-08-11 12:00 |
01:56:38.24 |
+08:37:53.5 |
HIP 9035 |
8.29 |
| 2026-08-12 00:00 |
01:56:48.69 |
+08:37:50.8 |
HIP 9035 |
9.74 |
| 2026-08-12 12:00 |
01:56:58.79 |
+08:37:45.9 |
HIP 9035 |
11.51 |
| 2026-08-13 00:00 |
01:57:08.54 |
+08:37:39.1 |
HIP 9035 |
13.41 |
| 2026-08-13 12:00 |
01:57:17.94 |
+08:37:30.3 |
HIP 9035 |
15.37 |
| 2026-08-14 00:00 |
01:57:26.98 |
+08:37:19.4 |
HIP 9035 |
17.32 |
| 2026-08-14 12:00 |
01:57:35.67 |
+08:37:06.5 |
HIP 9035 |
19.25 |
| 2026-08-15 00:00 |
01:57:44.00 |
+08:36:51.6 |
HIP 9035 |
21.12 |
| 2026-08-15 12:00 |
01:57:51.98 |
+08:36:34.8 |
HIP 9035 |
22.94 |
| 2026-08-16 00:00 |
01:57:59.61 |
+08:36:15.9 |
HIP 9035 |
24.69 |
| 2026-08-16 12:00 |
01:58:06.87 |
+08:35:55.0 |
HIP 9035 |
26.37 |
| 2026-08-17 00:00 |
01:58:13.78 |
+08:35:32.1 |
HIP 9035 |
27.97 |
| 2026-08-17 12:00 |
01:58:20.33 |
+08:35:07.2 |
HIP 9035 |
29.50 |
| 2026-08-18 00:00 |
01:58:26.52 |
+08:34:40.4 |
HIP 9035 |
30.95 |
| 2026-08-18 12:00 |
01:58:32.36 |
+08:34:11.5 |
HIP 9035 |
32.32 |
| 2026-08-19 00:00 |
01:58:37.83 |
+08:33:40.7 |
HIP 9035 |
33.62 |