The "Hubble" telescope is a reflective astronomical telescope set on the earth's orbit and used to explore cosmic objects. Its aperture is a circle with a diameter of 2.4m. What is the circumference of the light port of the "Hubble" telescope?
"哈勃"望远镜是设置在地球轨道上的用于探索宇宙目标的反射式天文望远镜，它的通光口是直径为2.4m的圆．"哈勃"望远镜通光口的周长是多少米？
<gadget id="calculator">3.14 * 2.4</gadget>
<output>7.536</output>

<result>7.536</result>