Augmier's Scorching Orbwondrous, rare

This odd contraption is composited of a small crystal orb set within a larger metal semi-sphere. As a bonus action you can press the button recessed into the metal sphere to activate it. The turn after it has been activated the orb levitates until it is 20 feet in the air, or as high as the above terrain will allow, and begins spinning as it glows a soft orange. Each turn it will make a ranged spell attack against the nearest creature it can see within range. It has a +5 spell attack modifier, a range of 30 feet for every 5 feet it is above the ground, and on a hit it deals 2d6 fire damage. After 10 minutes, or firing 10 times, it stops glowing, falls to the ground, and can not be activated again until the next dawn.