Did gold rain down from heaven?

Gold doesn't just fall from the sky-or does it? Well, it does if you believe the latest research from the University of Bristol, which says so.

LONDON, ENGLAND (Catholic Online) - Researchers studying the Earth's crust have concluded that our planet's core has more precious metals than expected, and some of the metals we see on the surface were likely brought here in a meteor shower. Scientists believe the meteors fell to Earth around four billion years ago.

Scientists examined some of the Earth's oldest rocks and found that when the Earth formed, the heaviest precious metals should have sunk into the core. Such a scenario would make heavy metals such as gold scarce, much more so than they are today.

Their explanation is that some of the metals we find came from meteors that showered Earth late in its formation, when the crust was already firm, but still long enough ago for many of those metals to be widely dispersed around the planet.

According to astronomers, all of the gold and other heavy metals in the solar system are not made on Earth, but rather came from space. As stars die, they explode (supernova) into great cosmic clouds of dust and gas. In the process of exploding, which takes only a matter of seconds, stars fuse atoms into heavier and heavier elements. This is how every metal, from iron on down in the periodic table is forged.

Later, as these clouds of dust and gas condense back into new planets and stars, the metals sink into their cores. This is why Earth's core is made mostly of molten iron, but is also rich in other metals. Researchers think, it is so rich that the only way to explain the metals on the surface is for them to arrive here after the cooling of the crust, which could have happened via meteorites. Astronomers point out that many meteorites which fall today often contain iron and other heavy metals.

Scientists use a similar theory to suggest that all of Earth's water was delivered via comet impacts after the crust cooled.

The study was published in the current issue of the scientific journal, Nature.

QUESTION OF THE DAY: What do you think? Do you believe meteorites brought gold to Earth? Enter your comments below.

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