In the accurate Indian Geometrical Model, the first trignometric correction is made to bring the planet to its heliocentric longitude. R Sin M, that is if the planet has traversed 42 degrees ( then Bhuja = 42 and Bhujajya = sin(42), therefore R Sin M = 206265 * Sin(42) is added to the Graha Madhyamam and the resultant value is its heliocentric longitude ! Western Astronomy uses M = E- e sin E.