Mass extinctions and the sun's encounters with spiral arms
نویسندگان
چکیده
منابع مشابه
Mass Extinctions and The Sun’s Encounters with Spiral Arms
The terrestrial fossil record shows that the exponential rise in biodiversity since the Precambrian period has been punctuated by large extinctions, at intervals of 40 to 140 Myr. These mass extinctions represent extremes over a background of smaller events and the natural process of species extinction. We point out that the non-terrestrial phenomena proposed to explain these events, such as bo...
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ژورنال
عنوان ژورنال: New Astronomy
سال: 1998
ISSN: 1384-1076
DOI: 10.1016/s1384-1076(97)00044-4