These look more like hovering robot eyes than planets, but Elipson’s Planet L Speakers have some nice specs. They use coaxial 2-way design with a 25mm soft dome tweeter and a 165mm paper-cone mid/woofer. Plus they have a great modern and space age look.

They feature a frequency response of 48Hz to 20,000Hz with 90dB sensitivity and 6-ohm impedance. Each weighs a hefty 15.4 pounds so mount them securely so they don’t fall on your head. They will cost you about $965 for a pair.