C/2011 M1 (LINEAR)

Metadata

Parameter Value
Designation C/2011 M1 (LINEAR)
Type C
Perihelion (tp_cal, UTC) 2011-09-07T13:44:21.122880Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:31:52Z
Obs used 109
NEO -
M1 12.300
K1 18.250
PC 0.030
Osculating Elements
Parameter Value
Epoch (epoch_cal, TDB) 2011-07-02.0000000
e 1.00267426
q (au) 0.895753
a (au) -334.952908
i (deg) 70.183172
Ω (om, deg) 324.795673
ω (w, deg) 119.568947
M (ma, deg) -0.010864

Magnitude

C/2011 M1 (LINEAR) · Magnitude (Full range)

Scatter + Global Linear

$$ M_a = (13.255 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

Model Parameters

Parameter Value
H0 13.255
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

Residuals (Piecewise)

$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$

Start (UTC) End (UTC) a b
2011-06-22 2011-07-13 +34.0421 -6.777
2011-07-13 2011-09-07 +17.3304 -3.287

log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)

Ephemeris

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-03-26 00:00 08:11:43.27 -88:08:35.3 HIP 38078 21.45
2026-03-26 12:00 08:10:54.16 -88:07:52.6 HIP 37199 21.52
2026-03-27 00:00 08:10:06.52 -88:07:09.6 HIP 37199 20.79
2026-03-27 12:00 08:09:20.31 -88:06:26.4 HIP 37199 20.08
2026-03-28 00:00 08:08:35.52 -88:05:42.9 HIP 37199 19.37
2026-03-28 12:00 08:07:52.13 -88:04:59.0 HIP 37199 18.68
2026-03-29 00:00 08:07:10.12 -88:04:15.0 HIP 37199 18.01
2026-03-29 12:00 08:06:29.46 -88:03:30.6 HIP 37199 17.35
2026-03-30 00:00 08:05:50.15 -88:02:46.1 HIP 37199 16.71
2026-03-30 12:00 08:05:12.16 -88:02:01.3 HIP 37199 16.09
2026-03-31 00:00 08:04:35.47 -88:01:16.2 HIP 37199 15.50
2026-03-31 12:00 08:04:00.07 -88:00:31.0 HIP 37199 14.93
2026-04-01 00:00 08:03:25.92 -87:59:45.5 HIP 37199 14.39
2026-04-01 12:00 08:02:53.02 -87:58:59.8 HIP 37199 13.89
2026-04-02 00:00 08:02:21.35 -87:58:13.9 HIP 37199 13.42
2026-04-02 12:00 08:01:50.88 -87:57:27.8 HIP 37199 12.99
2026-04-03 00:00 08:01:21.60 -87:56:41.6 HIP 37199 12.61
2026-04-03 12:00 08:00:53.49 -87:55:55.1 HIP 37199 12.27
2026-04-04 00:00 08:00:26.53 -87:55:08.5 HIP 37199 11.99
2026-04-04 12:00 08:00:00.70 -87:54:21.7 HIP 37199 11.77
2026-04-05 00:00 07:59:35.99 -87:53:34.8 HIP 37199 11.61
2026-04-05 12:00 07:59:12.38 -87:52:47.7 HIP 37199 11.51
2026-04-06 00:00 07:58:49.85 -87:52:00.4 HIP 37199 11.47
2026-04-06 12:00 07:58:28.38 -87:51:13.0 HIP 37199 11.50
2026-04-07 00:00 07:58:07.96 -87:50:25.5 HIP 37199 11.60
2026-04-07 12:00 07:57:48.57 -87:49:37.8 HIP 37199 11.76
2026-04-08 00:00 07:57:30.19 -87:48:50.1 HIP 37199 11.98
2026-04-08 12:00 07:57:12.82 -87:48:02.2 HIP 37199 12.25
2026-04-09 00:00 07:56:56.42 -87:47:14.2 HIP 37199 12.58
2026-04-09 12:00 07:56:40.99 -87:46:26.0 HIP 37199 12.97
2026-04-10 00:00 07:56:26.51 -87:45:37.8 HIP 37199 13.39
2026-04-10 12:00 07:56:12.96 -87:44:49.5 HIP 37199 13.86
2026-04-11 00:00 07:56:00.34 -87:44:01.1 HIP 37199 14.36
2026-04-11 12:00 07:55:48.61 -87:43:12.6 HIP 40861 14.58
2026-04-12 00:00 07:55:37.78 -87:42:24.0 HIP 40861 14.78
2026-04-12 12:00 07:55:27.83 -87:41:35.4 HIP 40861 15.02
2026-04-13 00:00 07:55:18.74 -87:40:46.7 HIP 40861 15.28
2026-04-13 12:00 07:55:10.49 -87:39:57.9 HIP 40861 15.58
2026-04-14 00:00 07:55:03.08 -87:39:09.0 HIP 40861 15.91
2026-04-14 12:00 07:54:56.49 -87:38:20.1 HIP 40861 16.26
2026-04-15 00:00 07:54:50.71 -87:37:31.2 HIP 40861 16.65
2026-04-15 12:00 07:54:45.72 -87:36:42.1 HIP 40861 17.05
2026-04-16 00:00 07:54:41.51 -87:35:53.1 HIP 40861 17.48