The Journey of Flight.pdf - Valkyrie Cadet

Chapter Chapter 24 24 - - - Space Space Environment
Environment
Interplanetar
Interplanetar
Interplanetary Interplanetar
Interplanetary
y y y Space Space Space Space Space
Interplanetary space is measured from the center of the Sun to the orbit of its outermost planet.
This planet, Pluto, has an orbit that extends as far as 4,566,000,000 miles from the Sun. Thus, the disc
of our interplanetary space has a maximum radius of 4,566,000,000 miles, or a maximum diameter of
over nine billion miles. In addition to the Sun, this portion of outer space contains nine known planets,
numerous planetary satellites, a huge “belt” of asteroids (small planets), charged particles, magnetic
fields, dust and more. This interplanetary space is often referred to as the Solar System.
Interstellar Interstellar Interstellar Interstellar Interstellar Space Space Space Space Space
On clear nights, nights free of clouds and air pollution, the Milky Way is visible. This is a common
name for the galaxy in which we reside, along with about 100 billion other solar systems and stars. The
distance between the extent of one solar system, and the beginning of another solar system, is called
interstellar space.
Distance between the stars and/or solar systems
varies and involves such high numbers of
miles that the imagination is staggered. In this
case, distance is thought of in light years and
parsecs instead of astronomical units. A light
year is the distance a photon can travel in one
of Earth’s calendar years. This amounts to 5 trillion
878 billion statute miles (5,878,000,000,000
miles). When the number of light years gets very
large, parsecs are used; one parsec is 3.26 light
years, or 19.2 trillion miles.
So, how far into this interstellar space would
a person travel to find another Sun and/or solar
system? Astronomers believe a person would
have to travel 4 1/3 years at the speed of light to
reach it. However, this would be a nearby solar
Overhead view of our galaxy. Seen face-on, the Milky
Way’s central bulge of stars is surrounded by spiral arms.
Characteristics Characteristics Characteristics Characteristics Characteristics of of of of of Our Our Our Our Our Sun Sun Sun Sun Sun
Sun
Sun
The force at the center of our solar system is the Sun. Although the Sun is only a medium-size star,
its dimensions, power, composition, temperature and other factors stagger the imagination. The Earth
has a diameter of a little less than 8,000 miles; the Sun’s diameter is 864,000 miles. The Sun is the
501
system. Other stars and solar systems are much
farther away.