| Parameter |
Value |
| Designation |
149P/Mueller 4 |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2010-02-18T16:52:27.373440Z |
| Orbit solution date (soln_date, UTC) |
2023-05-03T22:44:05Z |
| Obs used |
494 |
| NEO |
- |
| M1 |
15.500 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2013-05-05.0000000 |
| e |
0.38831799 |
| q (au) |
2.646439 |
| a (au) |
4.326494 |
| i (deg) |
29.754798 |
| Ω (om, deg) |
145.255090 |
| ω (w, deg) |
43.567077 |
| M (ma, deg) |
128.282351 |
Magnitude
Scatter + Global Linear
$$
M_a = (16.267 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
16.267 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.532 |
| k |
0.800 |
| δ90 |
10.000 |
| 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) |
| 2026-05-12 00:00 |
07:17:18.38 |
+11:38:33.0 |
HIP 35234 |
28.63 |
| 2026-05-12 12:00 |
07:17:54.62 |
+11:41:17.9 |
HIP 35234 |
29.30 |
| 2026-05-13 00:00 |
07:18:31.00 |
+11:44:01.1 |
HIP 35234 |
32.74 |
| 2026-05-13 12:00 |
07:19:07.52 |
+11:46:42.7 |
HIP 35234 |
38.23 |
| 2026-05-14 00:00 |
07:19:44.19 |
+11:49:22.7 |
HIP 35758 |
41.34 |
| 2026-05-14 12:00 |
07:20:20.99 |
+11:52:01.1 |
HIP 35758 |
32.37 |
| 2026-05-15 00:00 |
07:20:57.94 |
+11:54:37.9 |
HIP 35758 |
23.69 |
| 2026-05-15 12:00 |
07:21:35.03 |
+11:57:13.1 |
HIP 35758 |
15.82 |
| 2026-05-16 00:00 |
07:22:12.25 |
+11:59:46.8 |
HIP 35758 |
10.80 |
| 2026-05-16 12:00 |
07:22:49.61 |
+12:02:18.8 |
HIP 35784 |
8.04 |
| 2026-05-17 00:00 |
07:23:27.11 |
+12:04:49.2 |
HIP 35784 |
13.57 |
| 2026-05-17 12:00 |
07:24:04.74 |
+12:07:18.0 |
HIP 36027 |
20.41 |
| 2026-05-18 00:00 |
07:24:42.50 |
+12:09:45.3 |
HIP 36027 |
10.89 |
| 2026-05-18 12:00 |
07:25:20.40 |
+12:12:10.9 |
HIP 36027 |
1.77 |
| 2026-05-19 00:00 |
07:25:58.42 |
+12:14:35.0 |
HIP 36027 |
8.44 |
| 2026-05-19 12:00 |
07:26:36.58 |
+12:16:57.5 |
HIP 36027 |
18.01 |
| 2026-05-20 00:00 |
07:27:14.86 |
+12:19:18.4 |
HIP 36261 |
14.29 |
| 2026-05-20 12:00 |
07:27:53.27 |
+12:21:37.8 |
HIP 36261 |
11.57 |
| 2026-05-21 00:00 |
07:28:31.80 |
+12:23:55.6 |
HIP 36387 |
11.81 |
| 2026-05-21 12:00 |
07:29:10.46 |
+12:26:11.8 |
HIP 36387 |
2.11 |
| 2026-05-22 00:00 |
07:29:49.24 |
+12:28:26.4 |
HIP 36387 |
7.64 |
| 2026-05-22 12:00 |
07:30:28.14 |
+12:30:39.5 |
HIP 36387 |
17.38 |
| 2026-05-23 00:00 |
07:31:07.16 |
+12:32:51.1 |
HIP 36631 |
14.43 |
| 2026-05-23 12:00 |
07:31:46.30 |
+12:35:01.0 |
HIP 36631 |
5.63 |
| 2026-05-24 00:00 |
07:32:25.56 |
+12:37:09.5 |
HIP 36631 |
6.90 |
| 2026-05-24 12:00 |
07:33:04.94 |
+12:39:16.4 |
HIP 36631 |
16.03 |
| 2026-05-25 00:00 |
07:33:44.43 |
+12:41:21.7 |
HIP 36631 |
25.71 |
| 2026-05-25 12:00 |
07:34:24.03 |
+12:43:25.6 |
HIP 36843 |
25.22 |
| 2026-05-26 00:00 |
07:35:03.75 |
+12:45:27.8 |
HIP 37045 |
25.75 |
| 2026-05-26 12:00 |
07:35:43.58 |
+12:47:28.6 |
HIP 37045 |
15.85 |
| 2026-05-27 00:00 |
07:36:23.53 |
+12:49:27.9 |
HIP 37045 |
6.01 |
| 2026-05-27 12:00 |
07:37:03.58 |
+12:51:25.6 |
HIP 37045 |
4.31 |
| 2026-05-28 00:00 |
07:37:43.74 |
+12:53:21.8 |
HIP 37147 |
6.72 |
| 2026-05-28 12:00 |
07:38:24.01 |
+12:55:16.5 |
HIP 37147 |
9.14 |
| 2026-05-29 00:00 |
07:39:04.39 |
+12:57:09.7 |
HIP 37147 |
17.95 |
| 2026-05-29 12:00 |
07:39:44.88 |
+12:59:01.3 |
HIP 37147 |
27.61 |
| 2026-05-30 00:00 |
07:40:25.47 |
+13:00:51.5 |
HIP 37508 |
34.99 |
| 2026-05-30 12:00 |
07:41:06.16 |
+13:02:40.2 |
HIP 37508 |
28.43 |
| 2026-05-31 00:00 |
07:41:46.96 |
+13:04:27.4 |
HIP 37508 |
24.40 |
| 2026-05-31 12:00 |
07:42:27.87 |
+13:06:13.1 |
HIP 37508 |
24.25 |
| 2026-06-01 00:00 |
07:43:08.87 |
+13:07:57.3 |
HIP 37723 |
22.79 |
| 2026-06-01 12:00 |
07:43:49.98 |
+13:09:40.0 |
HIP 37723 |
18.99 |
| 2026-06-02 00:00 |
07:44:31.19 |
+13:11:21.2 |
HIP 37723 |
20.18 |