The "fact of the universe" or Space science it is a vacuum, its also called outer space. In the totality of all the
planetary systems, stars, nebulae, galaxies, galactic clusters, black holes, and the atoms and molecules that make all these objectives. There is no atmosphere in space or in the universe, here sound can not travel as there is no medium or way to sound can travel to be heard. It’s
a complete silent zone.
Astronauts use radios for their communication while in
space, radio waves can be sent and received. However,
space is not fully vacuumed but nearly-vacuum, because of some small number of
particles are there. Gas, dust and other bits of substance float around "vacant"
areas of the universe, while more crowded areas can host planets, stars, and
galaxies. For measuring the distance in space "light-years,"
representing the distance, it takes light to travel in a year (roughly 5.8
trillion miles, or 9.3 trillion kilometres).
The
universe or space is 13.5 billion years old and expanding since its birth. For this expansion, the universe is now assumed
to be about 91 billion light-years across.
We
do not have any idea other than generalizations that present universe, maybe
one or many, must have begun at some point, maybe 13.5 billion years ago when
all substances exploded out from a single point called Big-Bang. However, no
one does not have any idea or can even guess, that what was before Big-Bang.
What
is the Beginning of the Universe?
Big-Bang,
the beginning of the universe. The creation incident of the universe is called
the Big Bang. The incident was the beginning of space and time, as well as the continuous
expansion of space. Initially, the universe was in a hot, solid-state that
cooled later as it expanded. The baby universe was masked until about 400
million years after the Big Bang, the first stars started to form and the initial
galaxies started to develop. Our Galaxie called " Milky-way ". The
Milky Way is the galaxy that contains our Solar System, with the name
describing the galaxy's appearance from Earth: a hazy band of light seen in the
night sky formed from stars that cannot be individually distinguished by the
naked eye
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MILKY-WAY |
How
the universe expansion started?
At
the time of birth, the universe was started expanding of its sub-atomic
particles. As it cooled and sustained to expand, the hydrogen along with some
helium and lithium began to combine and the outcome of dark matter to create
stars. The stars themselves made up the earliest galaxies. All the stars used
up their lives creating heavier elements than hydrogen in their centres. When those
stars died, those elements were scattered to the interplanetary space in their
galaxies. It became the kernel material for the next creations of stars, and
helped create planets and life.
How the universe will end?
Many ideas are there about
the end of the universe. The ultimate destiny of the universe will be prejudiced by
its density, which means how
much mass it has. As per
cosmologists,
that the universe will expand more and continue forever, eventually
it will devote infinity approaching towards absolute zero. At times there will be no stars in the universe,
no heated nebulae, no galaxies, no life. As
per cosmologists, that called “heat death of the
universe”. This will not happen quickly, but the best timeframe for “heat death” is multiple trillions of years in the
future. However, It is
also not clear that what the ultimate destiny of the universe is. Currently, some cosmologists also consider that the universe will continue to expand,
ultimate cooling off, or “freezing out”, Which will result in the “heat death”.
As per astronomical standards, the
space near Earth is quite crowded, the list of space are, Geospace, Interplanetary
space, Interstellar space, Intergalactic space :
Geospace is the area of outer space near Earth. It
includes the upper region of the atmosphere and the magnetosphere. The Van Allen radiation belt lies within
this geospace. The space inside the magnetosphere is protected from radiation from
the Sun. It has a low level of electrically charged particles.
Interplanetary space is the space around the Sun and planets
of the Solar System. It has the solar wind, a
continuous stream of charged particles from the Sun. This stream creates a very
thin layer of the atmosphere called the heliosphere, for billions of
miles or kilometres into space. It's having the magnetic field generated
by the Sun. Planets such as Jupiter, Saturn, Mercury, and
the Earth also have magnetospheres. These magnetic fields can trap
particles from the solar wind and other sources, creating belts of magnetic
particles such as the Van Allen radiation belt. Planets without
magnetic fields, such as Mars, have their atmospheres gradually exposed
off by the solar wind.
Interstellar space is the physical space within the
galaxy which is not occupied by stars or their planetary systems. Most
of the mass in this space is made up of single hydrogen atoms,
fewer helium atoms and a few heavier atoms become stars.
Intergalactic space having 'cosmic vacuums' between the
large-scale structures of the universe.
Interesting Facts about Space :
- There is no sound in space because molecules are too far apart to transmit sound.
- The temperature of space is about −270.45 °C.
- Space is a hard vacuum, meaning it is a containing very little matter.
- As per the Kármán line is 100 km is an altitude above the Earth.
- The space between galaxies is not completely empty but has an average of one atom per cubic meter.
- The Milky Way, our Galaxy, having an estimated 100-400 billion stars.
- There are an estimated 2 trillion (2,000,000,000,000) galaxies.
- The universe is detected to be 13.7 billion years old and has been expanding since its formation in the Big Bang.
References :
1.Wikipedia The Outer space - https://simple.wikipedia.org/wiki/Outer_space#
2. NASA https://www.nasa.gov/
Photo by: Jeremy Thomas & Guthrie Kuckes