Some 2.7 billion years ago, the Earth's air weighed less than half what it does today, according to a study published Monday in the journal Nature Geoscience. This finding, if confirmed, would prompt a shift from the dominant viewpoint that that ancient atmosphere was twice as thick as today's, which in turn could change the solution to a longstanding scientific conundrum known as the "faint young sun paradox."
At the time, our sun was about 20 percent dimmer than it is now. That meant that the sun's rays wouldn't have warmed Earth's surface as readily....
http://m.csmonitor.com/Science/2016/0510/Our-air-weighed-a-lot-less-billions-of-years-ago-say-researchers
No comments:
Post a Comment