According to mainstream science, the moon gets its light from the sun.
The moon shines because its surface reflects light from the sun. And despite the fact that it sometimes seems to shine very brightly, the moon reflects only between 3 and 12 percent of the sunlight that hits it.
But is Jesus saying that the moon has its own light source in these passages?
Mark 13:24 (KJV) But in those days, after that tribulation, the sun shall be darkened, and the moon shall not give her light,
Matthew 24:29 (KJV) Immediately after the tribulation of those days shall the sun be darkened, and the moon shall not give her light, and the stars shall fall from heaven, and the powers of the heavens shall be shaken: