The Milky Way is the name of the galaxy we live in. It's a
barred spiral galaxy. We live in the Orionis spiral arm.
The distance
between stars is incredible. For example, if you scaled our
solar system (Sun and planets) into a model of about 2 inches, the
nearest star (Proxima Centauri) would be 4 miles away. Most of
the stars are about the same distance away from each
other.
There are no
stars between galaxies. All the stars and nebulae we see are
in our own Milky Way galaxy. Using telescopes, we can see
other galaxies .
The center
of our galaxy is extremely bright. If nebulae, dust clouds and
gas were not between us, we would not be able to see the stars at
night.
To
understand distance in space, you need to know about the light year.
The speed of
light is approximately 186,300 miles per second.
Traveling
the speed of light, you could travel around the Earth seven times in
1 second, to the Moon in 1 1/2 seconds, to the planets in our solar
system in a few hours and to the Sun in 8 minutes. To get to
Proxima Centauri, approximately 24 trillion miles, it would take 4
years.
The speed of
light travels about 6 trillion miles per year. This is known
as the light year. The light year is used to measure distance,
not time.
63,200
astronomical units (AU) equals 1 light year. 1 AU is the
distance between the Earth and the Sun (93 million miles).
Proxima
Centauri is about 270,000 AU or 4.3 light years from Earth. It
takes 4.3 years for its light to shine to Earth.
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