Large oval shaped object radiating green tint then bursting with speed into an orange hue.

During an astronomy visit, to Funks Grove south of Bloomington-Normal Illinois; several students and one professor witnessed a large oval with a luminous dark green tint hovering over a small corn field. Upon noticing the object facing north moved at first very slowly, and then with a almost radiant burst, the green tint faded into an almost brilliant orange. Upon this the object moved at an astounding speed and a small faint noise was heard. The object then proceeded to head South-east and then vanished from line a sight due to the speed and velocity in which it traveled.