2
Postinflation,
the universe is a
seething, hot soup of
electrons, quarks, and
other particles.The universe
The universe is unbelievably huge. It is everything
we can touch, feel, sense, measure, or detect. It
includes people, plants, stars, galaxies, dust clouds,
light, and even time. Scientists believe our universe
has existed for almost 14 billion years.
8TIME
1
Moments after the
Big Bang, the cosmos
goes through a superfast
“inflation.” It expands from
smaller than an atom to the
size of a grapefruit in a tiny
fraction of a second.3
A rapidly cooling
cosmos permits
quarks to clump into
protons and neutrons.4
Still too hot to form
into atoms, charged
electrons and protons
scatter light: the universe
is a superhot fog.ONE SECOND
SPACE FACT FILE
O Light from distant galaxies has taken
more than 12 billion years to arrive—so
we see them as they were before the
Earth was born.
O There are more stars in the universe
than there are grains of sand on all of
Earth’s beaches.
O In its first second, the universe grew
from smaller than an atom to about 1,
times the size of our solar system today.EXPANDING UNIVERSE
Across the visible universe, galaxies
are found to be moving away from
each other—a little like spots on an
inflating balloon. However, it is
actually space that is expanding. The
farther away from us galaxies are,
the faster they seem to
be moving.10 -43 seconds 10 -32 seconds 10 -6 seconds 3 minutes
TEMPERATURE^18 27°F (1027°C)^18 13°F (1013°C)^18 8°F (108°C)
Astronomers measure distance in light-
years. One light-year is the distance light
travels in one year. Visible light travels at
186,000 miles/second (300,000 km/
second) in space. It takes a long
time for light to reach
us from distant stars
and planets.
Telescopes are like
time machines,
allowing us to see
what things
looked like in
the past.PROTON
NEUTRON
QUARKS
ELECTRON
TIME BEGINS
SPACE
(c) 2012 Dorling Kindersley. All Rights Reserved.(c) 2012 Dorling Kindersley. All Rights Reserved.