3 of 8 spellin

Do you gain combat advantage when attacking a prone enemy with Flaming Sphere?

Daily ✦ Arcane, Conjuration, Fire, Implement
Standard Action Ranged 10
Flame Sphere: Effect: You conjure a Medium flaming sphere that occupies a
square within range, and the sphere attacks. Any creature that starts its turn adjacent to the sphere takes 1d4 + Intelligence modifier fire damage. As a move action, you can move the sphere 6 squares.
Target: One creature adjacent to the flaming sphere
Attack: Intelligence vs. Reflex
Hit: 2d6 + Intelligence modifier fire damage.
Sustain Minor: You can sustain this power until the end of the encounter. As a standard action, you can make an‑ other attack with the sphere

If flame sphere is created in a square adjacent to a prone enemy, does it gain combat advantage since it's making a melee attack against a prone target?

Related: Does the prone ranged defensive bonus apply to a creature hit by Flaming Sphere's initial attack?