Let's
consider a more realistic example: the Orion Constellation. Its seven
major stars appear in our Earthly sky as:
And
the constellation is often considered to look like this:
Orion
is one of the more fascinating constellations, because most
civilizations on Earth have tended to interpret this arrangement of
stars as a warrior or hunter, with the three middle stars in a
straight line seen as his belt, and the others as locating his arms
and legs.
All
of these perceptions view Orion as a two-dimensional figure, when
it's really a three-dimensional arrangement of stars—all at
different distances from us. In order to illustrate this, I
constructed a model Orion as a three-dimensional collection of stars
with cotton balls designating the brightest seven stars. I suspended
the cotton balls from a piece of cardboard and took a photo from one perspective to
demonstrate how Orion looks to us:
We
see the seven stars as a two-dimensional figure. The three cotton
balls that constitute the “belt” seem to be (pretty much) in a
straight line. Compare to the figures above.
Now,
if we could leave planet Earth and travel to some alternative point
in space to view these seven stars, they would appear different to
us. Let's move through “space” about 12o to the left.
(I did this by moving my camera 12o to the left and took
another photo. It looks like this:
This
is how those seven Orion stars would appear to beings who viewed the
constellation from this perspective. The four stars making up his
arms and legs still appear in similar locations, but what is that
triangular bundle of stars in the middle? Would people on this
distant world consider them to be a belt (assuming that these aliens
even had a waist and wore belts)? What kind of figure would they see
in this arrangement of Orion's stars?
(By
the way, if you “do the numbers,” the 12o shift in
perspective of Orion that I describe above would constitute a spatial
travel distance of about 140 light years from where we Earthlings
reside. That's a hell of a move through space—it's over 30 times
the distance to the nearest star: Proxima Centauri, which is about
4.3 light years away. If we were to take this trip on a space ship
that could travel five times faster than anything humans have
achieved so far, the trip would take nearly 1,000 years to make.
That's one measure of how big even local space is.)
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