S***n 发帖数: 330 | 1 (From Bad Astronomy Blog ... http://www.badastronomy.com/bablog/page/3/)
OK, so that title doesn’t thrill you. But that simple statement is actually
the answer to a long-standing mystery. Ready for this? OK, sit back…
You may already know that massive stars — stars with something like 20 or
more times the mass of the Sun — explode when they end their lives. You may
not know that for thousands of years before this, they blow off a sort of
super-solar wind, dumping quite a bit of gas into space ar |
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