I give two examples as to why intelligent life may not
actually exist, though I admit that for me, or even for a physicist who devoted
his or her entire life to researching and studying the universe, it's shocking
to claim that completely no life exists elsewhere.
Keeping that in mind, I'd just like to consider
conditions elsewhere in the known universe. You really only need to look at our
own solar system or the Earth at certain periods in its own history to
appreciate that most places are much worse and much less suitable for life than
our mild, watery globe.
So far, space scientists have discovered about seventy
planets outside the solar. But it appears that if you wish to have a planet
suitable for life, you just have to be very lucky, and the more advanced the
life is, the luckier you'll have to be. I'm by no means a space observer, but I
can recognize some particularly fortunate breaks we've had on the Earth. For
example:
We are, to a degree, at the right distance from the
perfect type of star, the one that is big enough to radiate a huge amount of
energy, but not so big as to bum itself out quickly. Had our sun been ten times
as huge, it would have burnt out completely after only ten million years,
instead of ten billion and surely we would not exist. Too near, everything on
the Earth would have boiled and withered away; any further, everything would
have frozen over.
The universe is a surprising place, and our existence
within it is a wonder. If a long and unimaginably complex sequence of events
dating back 4.6 billion years or so hadn't happened in a particular manner at a
particular time --if, to take just one example, the dinosaurs hadn't been wiped
out by a meteor(流星)--we might still be a few centimeters
long, with whisker(胡须) and a tail, and you'll be reading this in
a cave somewhere.
1.What's
the best title for this passage?
A. No Life Exists out of the Earth
B. Seventy Planets Discovered
C. A Place Full of Wonders
D. Perfect Conditions for Life
2.What
makes the Earth more suitable for life than other planets in the solar system?
A. The Earth is the only planet that can receive
energy from the sun.
B. The sun is at the right distance from us and in
proper size.
C. The distance between the planets was neither too
long nor too near.
D. The dinosaurs were no longer a threat to the Earth.
3.What
does the underlined phrase "withered away" in the 4th paragraph mean?
A. Exploded. B. Expanded. C.
Floated away. D. Dried and died.
4.Where
does the text probably come from?
A. A history book. B. A magazine. C.
A science fiction. D. A famous
novel.