Even if you never leave your house, you will cover about a trillion miles
in your lifetime. How? Read on.
You travel more than you realize, whether you're a seasoned traveler or a
homebody.
That would be accurate even if you remained absolutely still your whole
life. So how much travel does the average individual do over their lifetime?
Whether or whether you think of Earth as your vehicle will determine the
response.
The average person will travel 30,000 to 50,000 miles (50,000 to 80,000
kilometers) on Earth's surface throughout their lifetime, while some world
travelers may go considerably farther. That's an astonishingly huge distance
- enough to round the planet at least once — especially given that most
people accrue the majority of this miles via commutes and brief
errands.
Even so, that amount is little compared to the motion we experience just by
riding along on Earth. The axis of our world is in motion. Earth spins like
a single rigid body and is essentially solid, thus everyone on the globe
traverses a full round every 24 hours and experiences the same angular
speed.
On the other hand, if you were to stand on the north or south poles, you
wouldn't really move anywhere; instead, you would simply spin in place.
However, those on the equator benefit greatly from this revolution, gaining
about 1,000 mph (1,600 km/h) in linear speed.
However, since most individuals don't reside near the equator, we may
estimate that the typical person moves at a constant speed of about 1,500
km/h (930 mph). (As we shall see, accuracy is not really relevant here.)
Each person travels around 600 million miles (1 billion kilometers)
throughout the course of an average lifespan of 80 years.
That's a huge improvement over the journey we make on Earth's surface, but
it's only the beginning. Earth not only rotates, but also orbiting the sun.
Our planet occasionally moves more swiftly or slowly depending on its
distance from the sun due to the elliptic nature of its orbit. However, the
average speed of Earth's orbit is roughly 30 km/s (19 mi/s).
That translates to over 600 million miles (1 billion km) annually. Each of
us thus covers around 50 billion miles (80 billion km) in our lifetimes,
which again dwarfs the distance we cover as a result of the planet's
rotation alone.
But there are other moving objects in the cosmos besides Earth. The Milky
Way galaxy's galactic core is where the sun orbits in a protracted,
leisurely fashion. These "galactic years" last around 230 million Earth
years. To put that in context, life first appeared on Earth around 17
galactic years ago, and the sun will expire in only 25 more.
A human lifespan is hardly apparent in relation to these massive cosmic
dimensions, and the sun is barely moving along its circle. But on a human
scale, it's virtually unfathomable; each of us will travel over 370 million
miles (600 billion km) in our lifetime owing to the speed of the sun
orbiting the Milky Way's core.
And that's not the end of it. Additionally, the entire galaxy is moving.
The universe is expanding, thus all galaxies are, on average, moving away
from one another. Each galaxy also moves independently, which astronomers
refer to as having a "peculiar velocity." towards instance, the Milky Way
and the Andromeda galaxy, which is closest to us, are headed towards
collision. These galaxies will start to merge in roughly five billion years
because of their gravitational pull to one another, which is strong enough
to overcome the universe's overall expansion.
Additionally, the Milky Way and Andromeda are traveling in the direction of
the Virgo cluster, a vast group of galaxies about 65 million light-years
away. Beyond that, the Great Attractor, the core of our supercluster termed
Laniakea, is where the Virgo cluster and its surrounding galaxies are all
traveling.
By analyzing the cosmic microwave background (CMB), which is made up of
radiation generated when our universe cooled from a plasma state when it was
just 380,000 years old, astronomers may determine the cumulative velocity of
these gravitational effects. It permeates the entire cosmos and is identical
to one part in a million wherever in the sky.
The CMB will reflect any motion in the cosmos. Light will undergo a Doppler
shift, going from higher frequencies in the direction we're travelling
toward to lower frequencies in the direction we're moving away from.
Astronomers may determine our overall cosmological velocity by observing
this shift, and their calculations provide a value of about 390 miles per
second (630 km per second).
Over an 80-year lifespan, that amounts to a cumulative travel of 930
billion miles (1.5 trillion km). You will still go that great distance even
if you never leave your house; that's quite an accomplishment!
