| 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) |
| 2026-09-20 00:00 |
01:52:20.47 |
+06:58:15.6 |
HIP 8617 |
23.17 |
| 2026-09-20 12:00 |
01:52:04.31 |
+06:55:57.8 |
HIP 8617 |
18.63 |
| 2026-09-21 00:00 |
01:51:47.90 |
+06:53:39.1 |
HIP 8617 |
14.09 |
| 2026-09-21 12:00 |
01:51:31.25 |
+06:51:19.5 |
HIP 8617 |
9.64 |
| 2026-09-22 00:00 |
01:51:14.36 |
+06:48:58.9 |
HIP 8617 |
5.66 |
| 2026-09-22 12:00 |
01:50:57.23 |
+06:46:37.4 |
HIP 8617 |
4.19 |
| 2026-09-23 00:00 |
01:50:39.88 |
+06:44:15.0 |
HIP 8617 |
7.15 |
| 2026-09-23 12:00 |
01:50:22.29 |
+06:41:51.8 |
HIP 8617 |
11.59 |
| 2026-09-24 00:00 |
01:50:04.49 |
+06:39:27.8 |
HIP 8587 |
14.11 |
| 2026-09-24 12:00 |
01:49:46.47 |
+06:37:03.1 |
HIP 8587 |
17.13 |
| 2026-09-25 00:00 |
01:49:28.24 |
+06:34:37.6 |
HIP 8587 |
21.01 |
| 2026-09-25 12:00 |
01:49:09.80 |
+06:32:11.3 |
HIP 8587 |
25.40 |
| 2026-09-26 00:00 |
01:48:51.16 |
+06:29:44.5 |
HIP 8587 |
30.09 |
| 2026-09-26 12:00 |
01:48:32.32 |
+06:27:16.9 |
HIP 8254 |
34.73 |
| 2026-09-27 00:00 |
01:48:13.29 |
+06:24:48.8 |
HIP 8254 |
30.56 |
| 2026-09-27 12:00 |
01:47:54.08 |
+06:22:20.0 |
HIP 8254 |
26.76 |
| 2026-09-28 00:00 |
01:47:34.68 |
+06:19:50.7 |
HIP 8254 |
23.55 |
| 2026-09-28 12:00 |
01:47:15.10 |
+06:17:20.9 |
HIP 8254 |
21.23 |
| 2026-09-29 00:00 |
01:46:55.35 |
+06:14:50.6 |
HIP 8267 |
18.68 |
| 2026-09-29 12:00 |
01:46:35.44 |
+06:12:19.9 |
HIP 8267 |
15.17 |
| 2026-09-30 00:00 |
01:46:15.36 |
+06:09:48.7 |
HIP 8267 |
13.15 |
| 2026-09-30 12:00 |
01:45:55.13 |
+06:07:17.2 |
HIP 8267 |
13.38 |
| 2026-10-01 00:00 |
01:45:34.74 |
+06:04:45.3 |
HIP 8267 |
15.79 |
| 2026-10-01 12:00 |
01:45:14.21 |
+06:02:13.1 |
HIP 8267 |
19.62 |
| 2026-10-02 00:00 |
01:44:53.54 |
+05:59:40.6 |
HIP 8064 |
23.91 |
| 2026-10-02 12:00 |
01:44:32.74 |
+05:57:07.9 |
HIP 8064 |
18.32 |
| 2026-10-03 00:00 |
01:44:11.80 |
+05:54:35.0 |
HIP 8064 |
12.87 |
| 2026-10-03 12:00 |
01:43:50.74 |
+05:52:01.8 |
HIP 8064 |
7.91 |
| 2026-10-04 00:00 |
01:43:29.56 |
+05:49:28.6 |
HIP 8064 |
5.24 |
| 2026-10-04 12:00 |
01:43:08.27 |
+05:46:55.3 |
HIP 8064 |
7.83 |
| 2026-10-05 00:00 |
01:42:46.88 |
+05:44:21.9 |
HIP 8064 |
12.85 |
| 2026-10-05 12:00 |
01:42:25.38 |
+05:41:48.5 |
HIP 8064 |
18.42 |
| 2026-10-06 00:00 |
01:42:03.79 |
+05:39:15.1 |
HIP 7884 |
13.74 |
| 2026-10-06 12:00 |
01:41:42.12 |
+05:36:41.8 |
HIP 7884 |
8.46 |
| 2026-10-07 00:00 |
01:41:20.36 |
+05:34:08.5 |
HIP 7884 |
5.08 |
| 2026-10-07 12:00 |
01:40:58.52 |
+05:31:35.4 |
HIP 7824 |
5.82 |
| 2026-10-08 00:00 |
01:40:36.62 |
+05:29:02.5 |
HIP 7824 |
5.61 |
| 2026-10-08 12:00 |
01:40:14.65 |
+05:26:29.8 |
HIP 7824 |
10.08 |
| 2026-10-09 00:00 |
01:39:52.62 |
+05:23:57.4 |
HIP 7701 |
15.49 |
| 2026-10-09 12:00 |
01:39:30.55 |
+05:21:25.3 |
HIP 7701 |
14.44 |
| 2026-10-10 00:00 |
01:39:08.43 |
+05:18:53.5 |
HIP 7701 |
15.82 |
| 2026-10-10 12:00 |
01:38:46.27 |
+05:16:22.0 |
HIP 7701 |
19.11 |
| 2026-10-11 00:00 |
01:38:24.08 |
+05:13:51.0 |
HIP 7701 |
23.53 |