We’ve known for a while that large astronomical events can spell bad
news for life: supernovae unleash unimaginable levels radiation,
asteroids can kick up climate-killing clouds, and black holes can suck
things out of existence altogether. Now it seems that simply wandering
too close to big star can evaporate a planet before it even forms.
University of Arizona astronomers have surveyed a thousand stars in the
Rosette Nebula - that might sound like a song lyric, but we assure you
it’s real scientific study. This strange object is located near one end of a giant molecular cloud in the Monoceros region of the Milky Way Galaxy. The astronomers found that most of the stars which ventured too close to O Stars were barren, stripped of even the
potential of forming planets.
“O Stars” are the brightest and hottest of the main sequence stars.
Gigantic surface temperatures of 30,000 Kelvin upward puts them at the
blue end of the spectrum. They can be a hundred times the size and
over a thousand times brighter than the friendly little G Star we call
“The Sun”.
The recent work shows that the massive solar winds and radiation output
from these hyper-bright lights in the night can strip away the dust
disk that surrounds young stars, the raw material that could otherwise
go into planet formation. To get some idea of the scale of the
radiation involved, the danger zone extends 1.6 light years from the O
stThe scientists say that an already-extant planet could possibly survive
a dalliance with these Death Stars, but I think they misunderstand our
concerns. We aren’t actually concerned about the dainty little
zettaton ball of rock; anything capable of beating up on a baby planet
will certainly vaporize anything carelessly making a living on the
surface. So our space searches for interesting planets can safely
ignore anything within those danger zones.
Don’t worry though, there aren’t any O Stars within sixteen light years
of Earth. As you can tell by the fact that you’re actually reading
this.
Posted by Luke McKinney.
Source:
http://www.livescience.com/space/070418_star_dangerzone.html
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