Earthlike Planets Could Have Formed at Almost Any Time in the Milky Way’s Evolution
Building a terrestrial planet requires raw materials that weren’t available in the early history of the universe. The Big Bang filled space with hydrogen and helium. Chemical elements like silicon and oxygen - key components of rocks - had to be cooked up over time by stars. But how long did that take? How many of such heavy elements do you need to form planets, especially rocky, Earthlike planets?
Studies have shown that Jupiter-sized gas giants tend to form around stars containing more heavy elements than the Sun. However, research by a team of astronomers found that planets smaller than Neptune are located around a wide variety of stars, including those with fewer heavy elements than the Sun. Astronomers call chemical elements heavier than hydrogen and helium “metals.” As a result, rocky worlds like Earth could have formed earlier than expected in the universe’s history.
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Earthlike Planets Could Have Formed at Almost Any Time in the Milky Way’s Evolution

Building a terrestrial planet requires raw materials that weren’t available in the early history of the universe. The Big Bang filled space with hydrogen and helium. Chemical elements like silicon and oxygen - key components of rocks - had to be cooked up over time by stars. But how long did that take? How many of such heavy elements do you need to form planets, especially rocky, Earthlike planets?

Studies have shown that Jupiter-sized gas giants tend to form around stars containing more heavy elements than the Sun. However, research by a team of astronomers found that planets smaller than Neptune are located around a wide variety of stars, including those with fewer heavy elements than the Sun. Astronomers call chemical elements heavier than hydrogen and helium “metals.” As a result, rocky worlds like Earth could have formed earlier than expected in the universe’s history.

Continue Reading