The Moon...
Removing the barrier between the two worlds and demonstrating His control of everything in existence, Allah also states that He manages the affairs on Earth from the Heaven, in a day which is equivalent to 1000 years of that you count (enumerate). Ironically, the Quran had spoken about the relativity (theory) some 1200 years before the birth of Albert Einstein. Historically, the Arabs used to use the units of time to indicate to long distances travelled.
Here, if you substitute the 1000 years by the intended distance travelled by the Moon as it revolves around the Earth 12,000 times and divide that distance by 1 day converted to seconds, you get: Speed of light = distance travelled by the Moon in 1000 years/(24x3600) = 299748 Km/s. This speed of light was adopted in a Scientific Conference in Paris, in 1984.
Similar to the concept of minor, middle, and major resurrections, here I submit: Physics (realm of the Physical world); and, Metaphysics I, Metaphysics II to refer to two worlds in the Unseen. The Physical world, for being material in nature, is being experienced by the majority of the children of Adam. For man's ignorance about the other worlds (which are spiritual in nature), very many generations of human beings do not know what they have missed. Seeing is believing, the adage goes.
But with what eyes? True: the naked eyes only see the material objects. For investigating tiny particulate matters (or distant heavenly planets), the scientists have utilized powerful microscopes. High resolution cameras can picture even the nuclei of living and pathological cells. One is not sure where to place the lie detectors, when the occupants of the Oval office lie with impunity.
After the recent technological breakthroughs, we started believing many things which we can not normally see by our naked eyes. Wireless communication was a dream a few decades ago. The Quran talks about Joseph's dream in seeing the Sun, the Moon, and 11 stars bowing down to him.