Tens to tons of of 1000’s of years earlier than a serious volcanic eruption, magma builds up beneath the surface of the Earth. In the magma, crystals of zirconium silicate (called zircons), as well as other crystals, form. These zircon crystals are tiny — only a tenth of a millimeter lengthy — but they’re the Daha fazla okuyun7 3 Courting Planetary Surfaces Astronomy 2e[…]