120P/Mueller 1

Metadata

Parameter Value
Designation 120P/Mueller 1
Type P
Perihelion (tp_cal, UTC) 2004-09-29T10:29:13.793280Z
Orbit solution date (soln_date, UTC) 2022-02-14T01:12:50Z
Obs used 147
NEO -
M1 6.600
K1 26.250
PC 0.030
Osculating Elements
Parameter Value
Epoch (epoch_cal, TDB) 2007-09-06.0000000
e 0.33653878
q (au) 2.743863
a (au) 4.135679
i (deg) 8.791195
Ω (om, deg) 4.442767
ω (w, deg) 30.008025
M (ma, deg) 125.574538

Magnitude

120P/Mueller 1 · Magnitude (Full range)

Scatter + Global Linear

$$ M_a = (11.540 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

Model Parameters

Parameter Value
H0 11.540
n 6.000
gf 1.000
gb -0.500
k 1.000
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

Ephemeris

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-05-12 00:00 15:50:21.43 -29:30:45.9 HIP 77664 16.28
2026-05-12 12:00 15:50:01.66 -29:30:13.6 HIP 77457 15.18
2026-05-13 00:00 15:49:41.84 -29:29:40.3 HIP 77457 10.84
2026-05-13 12:00 15:49:21.97 -29:29:06.1 HIP 77457 6.49
2026-05-14 00:00 15:49:02.04 -29:28:31.1 HIP 77457 2.21
2026-05-14 12:00 15:48:42.07 -29:27:55.1 HIP 77457 2.44
2026-05-15 00:00 15:48:22.05 -29:27:18.3 HIP 77457 6.76
2026-05-15 12:00 15:48:02.00 -29:26:40.6 HIP 77374 9.08
2026-05-16 00:00 15:47:41.91 -29:26:02.0 HIP 77374 7.20
2026-05-16 12:00 15:47:21.78 -29:25:22.6 HIP 77374 7.76
2026-05-17 00:00 15:47:01.63 -29:24:42.3 HIP 77374 10.38
2026-05-17 12:00 15:46:41.45 -29:24:01.1 HIP 77374 13.96
2026-05-18 00:00 15:46:21.25 -29:23:19.1 HIP 77220 13.32
2026-05-18 12:00 15:46:01.03 -29:22:36.3 HIP 77220 11.75
2026-05-19 00:00 15:45:40.79 -29:21:52.7 HIP 77220 11.77
2026-05-19 12:00 15:45:20.55 -29:21:08.2 HIP 77220 13.37
2026-05-20 00:00 15:45:00.30 -29:20:23.0 HIP 77220 16.09
2026-05-20 12:00 15:44:40.04 -29:19:36.9 HIP 77220 19.47
2026-05-21 00:00 15:44:19.79 -29:18:50.0 HIP 76986 19.33
2026-05-21 12:00 15:43:59.54 -29:18:02.4 HIP 76986 16.75
2026-05-22 00:00 15:43:39.29 -29:17:14.0 HIP 76986 15.08
2026-05-22 12:00 15:43:19.06 -29:16:24.8 HIP 76986 14.67
2026-05-23 00:00 15:42:58.83 -29:15:34.9 HIP 76986 15.60
2026-05-23 12:00 15:42:38.63 -29:14:44.3 HIP 76851 14.66
2026-05-24 00:00 15:42:18.45 -29:13:52.9 HIP 76851 10.71
2026-05-24 12:00 15:41:58.29 -29:13:00.8 HIP 76851 7.41
2026-05-25 00:00 15:41:38.16 -29:12:08.0 HIP 76851 5.94
2026-05-25 12:00 15:41:18.06 -29:11:14.5 HIP 76851 7.48
2026-05-26 00:00 15:40:57.99 -29:10:20.3 HIP 76851 10.81
2026-05-26 12:00 15:40:37.96 -29:09:25.4 HIP 76728 7.93
2026-05-27 00:00 15:40:17.97 -29:08:29.8 HIP 76728 5.55
2026-05-27 12:00 15:39:58.02 -29:07:33.6 HIP 76728 6.20
2026-05-28 00:00 15:39:38.12 -29:06:36.8 HIP 76728 9.27
2026-05-28 12:00 15:39:18.27 -29:05:39.3 HIP 76728 13.14
2026-05-29 00:00 15:38:58.47 -29:04:41.2 HIP 76728 17.29
2026-05-29 12:00 15:38:38.73 -29:03:42.5 HIP 76728 21.54
2026-05-30 00:00 15:38:19.05 -29:02:43.2 HIP 76496 19.79
2026-05-30 12:00 15:37:59.43 -29:01:43.3 HIP 76496 18.51
2026-05-31 00:00 15:37:39.87 -29:00:42.9 HIP 76448 15.78
2026-05-31 12:00 15:37:20.38 -28:59:41.8 HIP 76448 13.89
2026-06-01 00:00 15:37:00.97 -28:58:40.3 HIP 76448 13.24
2026-06-01 12:00 15:36:41.63 -28:57:38.2 HIP 76448 14.01
2026-06-02 00:00 15:36:22.36 -28:56:35.5 HIP 76318 14.96