True mass of an exoplanet can be obtained dividing minimum mass value by the sine of the inclination
To say:
Mass
min = 6 Jupiter masses
Inclination = 1.5° and sin i = ca. 0.02356
Mass
true = 6 : 0.02356 = ca. 254.7 Jupiter masses = ca. 0.25 Solar masses.
This works well til the inclination is 90°, i.e. when planet is coplanar, right? When minimum and true mass coincide.
Things get strange when inclination value is greater than 90, and this is the case of HD 5388 b.
Its minimum mass was set at Mass
min= 1.96 Jupiter masses and inclination value derived is i = 178.3°
If I obtain sine of 178.3, I get 0.334 and doing the math the true mass I obtain is 5.87 Jupiter masses rather 69 ± 20 Jupiter masses displayed
here.
Where's the error? Is there something I should add to calculation I am missing?
I need this answer for a planet building in a highly inclined binary system.
Thanks