Astronomers Have now Solved a Key Mystery about the Origin of Life

If a huge solar storm struck the Earth today, it could wipe out our technology and hurl us back to the dark ages. Lucky for us, events like this are quite rare. But four billion years ago, extreme space weather was probably the norm. And rather than bringing the apocalypse, it might have kick started life.
That’s the startling conclusion of explore published in Nature Geosciences today, which builds on an earlier discovery about young, sun-like stars made with NASA’s Kepler Space Telescope. Baby suns, it turns out, are extremely eruptive, releasing mind-boggling amounts of energy during “solar super flares” that make our wildest space weather look like drizzle.
Now, NASA’s Vladimir Airapetian has shown that if our sun was equally active 4 billion years ago, it could have made the Earth more habitable. According to Airapetian’s models, as solar super flares pounded our atmosphere, they initiated chemical reactions that yielded climate-warming greenhouse gases and other essential ingredients for life.
“The Earth should have been in a deep freeze four billion years ago,” Airapetian told Gizmodo, referring to the “faint young sun paradox” first raised by Carl Sagan and George Mullen in 1972. The paradox came about when Sagan and Mullen realized that Earth had signs of liquid water as early as Four billion years ago, while the sun was only 70 percent as bright as it is today. “The only way [to explain this] is to some-how incorporate a greenhouse effect,” Airapetian said.
Another early Earth puzzle is how the first biological molecules—DNA, RNA and proteins—scavenged enough nitrogen in order to form. Similar to today, the ancient Earth’s atmosphere was composed primarily of inert nitrogen gas (N2). While specialized bacteria called “nitrogen fixers” finally figured out how to break N2 and turn it into ammonia (NH4), early biology lacked this ability.
The latest study offers an elegant solution to both of these problems in the form of space weather. The research began some years back, when Airapetian was studying the magnetic activity of stars in NASA’s Kepler database. He discovered that G-type stars (stars like our sun) are like dynamite in their youth, frequently releasing pulses of energy equivalent to over 100 trillion atomic bombs. The most powerful solar storm ever experienced by humans, the 1859 Carrington event that caused worldwide power outages, pales in comparison.
Astronomers Have now Solved a Key Mystery about the Origin of Life
“It is a crazy amount of energy. I can hardly comprehend it myself,” Ramses Ramirez—an astrobiologist at Cornell University who was not involved with the study but collaborates with Airapetian—told Gizmodo.

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