If the Sun was blocked for a century by a gas cloud, freezing everything, or a nearby stellar explosion frying planetary surfaces, cave dwellers might be able to survive.
]]>Add the possibility of a http://antwrp.gsfc.nasa.gov/apod/ap991214.html]gas cloud coming between Earth and the Sun.
Dark matter, dark energy, what other lurks, unseen, ready to destroy ?
Interstellar or intergalactic objects will have very high energy of motion.
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Direct to Mars, colonizing, would give humans a better chance,
to adapt and escape disaster.
That is an understatement. At some future date, Belsole explained, several billion years from now, the local group of galaxies containing the Milky Way will be torn apart by a merger with the nearby Virgo cluster.
Even hiding several miles below the surface, on Mars, may be unsafe.
We cannot hide, but how can we run somewhere to escape ?
only a billion years from now is not that long a time.
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