This slideshow explains how scientists measured the size of the universe and its age, It is a miracle that this can even possible to do. The slide show also explain the discovery of the Redshift and the expanding universe. The evolution, the history and the major structure of our universe. It is only within our lifetime, these sorts of question about our origin was asked.
1. First created 14 Feb 2019. Version 1.0 - 18 Jun 2020. Daperro. London.
Our Universe
Size, Time, Evolution and Structure
2. Our universe is 13.7 billion years old and 93 billion light-years across
The is the oldest image of our universe. It is the cosmic microwave background (CMB),
showing the distribution of hydrogen clouds, when our universe was 380,000 years old.
The universe is approximately 3 times as old as our solar system.
3. Space-Time
Our universe exists in a medium called Space-Time. Space-Time is distorted by the presence of
matter (as shown above in a two dimensional world). The distortion of Space-Time led to gravity
between masses. We also know Space-Time is expanding (but we don’t know why).
5. Speed of light
The speed of light is 300,000 km per second. It takes 500 seconds for the sunlight to reach the
Earth. The light is the fastest speed possible. Nothing can travel fastest than light, as we know.
7. For relatively near objects we can use the earth orbit as a base line to measure distances.
Measuring of distance by Geometry
8. Measuring of distance by Brightness – Standard Candle
If we know the absolute brightness (magnitude) of a star then from the apparent brightness of
a similar star, we can work out the relative distance between them. So the first thing is to find
a type of star, with a known magnitude. Astronomers call this a ‘Standard Candle’ for
measuring astronomical distances. The most commonly used standard candles are Cepheid
Variable stars and RR Lyrae. In both cases the absolute magnitude of the star can be
determined from the variability period (see above).
9. Different types of Standard Candle
As the distances in the universe is vast we need to use different standard candles to measure
different distances.
10. The size of our Universe is unimaginably
huge, with 100 billion galaxies. Each
contains 100,000 million stars.
93 billion Light Years across
The size of our
observable
universe is 93
billion Light-
Years across.
11. This is the eXtreme Deep Field (XDF) view of our universe, population with some 500 galaxies.
The distant galleries are near the edge of the Observable Universe. It is a combination of 10
years of photographs for a tiny area of the sky, .
The furthest we can see
Expanding
Universe
12. The Expanding Universe – Red Shift
Light changes colour when moving toward and away from us. The changes in colour become
noticeable, when objects are moving very fast. In general we found that our universe is
expanding. The further the object from us the faster they move away from us.
13. With huge distances and huge speeds are involved, the visible light emitted by distant objects
have moved into the microwave spectrum.
14. Because of the expanding universe, the further away an object from us then the faster it is
moving away from us. Therefore the Redshift would be greater. So we have another way we
can use to estimate its distance by using the Redshift.
Redshift and distance
15. Age of our
Universe
Abell Cluster 2218 2 billion light-years away, in the constellation of Draco, showing
gravitational lensing, in which light is spent by the presence of a heavy mass.
16. There is another way to find out the age of the universe by finding the oldest object in the
universe. This is similar to finding the oldest stone on Earth to determine the Earth’s age.
Age of the Universe
17. The Rate pf Expansion
Now that we have worked out the size of the universe. If we can found out how fast the
universe is expanding, then we can work out the age of the universe.
Time (age) = Distance (size of universe) / Rate of Expansion
18. The age of
our universe
is 13.8
billion years
old
13.8 billion years old
19. The study on the globular
cluster M4, put the age of the
white dwarf stars between 12
to 13 billion years old. By
adding the one billion years it
took the cluster to form after
the Big Bang, astronomers
found that the age of the
white dwarfs agrees with
previous estimates that the
universe is 13 to 14 billion
years old. .
Age of White Dwarf Stars
20. Age of the Oldest Star
The oldest star 13.6 billion years old, within our own galaxy.
21. The Oldest Galaxy
This is the oldest galaxy GN-z11 founded, at 13.4 billion years old, at 32 billion light-years
away, just 400 million years after the Big Bang. Discovered in 2016.
23. The Early Universe
According to the Big Bang Theory, the our universe began from nothing. It has been growing
since. The early universe was filled with exotic particles that we can create today in huge
particle accelerators. After about 300,000 years hydrogen atoms were formed thus created
the Cosmic Microwave Background (CMB) that we see today.
Atom
300,000 years.
Cosmic Microwave
Background
24. The Early Universe
The atoms were formed after 350,000 years, when the universe was cooled down sufficiently.
25. Very early on fusion may have taken place when particles were densely packed. By the time when hydrogen
atoms began to form we have the Cosmic Microwave Background. After that the universe went through a
long period of Dark Age. During this time hydrogen atoms were pulled together by gravity to pockets of
dense gas clouds, that led to the formation of stars, which began to shine.
The Dark Ages and First Light
26. First Stars
In the young universe, early stars
(Population III) were made of mainly
hydrogen (75%) and helium (25%), with tiny
amount of lithium, etc. They are about 10
times larger and 100 of times heavier than
stars today. It was in their cores that
heavier elements were made like iron,
carbon, oxygen etc. They burnt our very
quickly and ending as exploding
supernovas.
Artist impression of a ‘First Star’, a Blue Giant.
27. The Oldest Galaxy
The Yeti Galaxy (actually dust clouds) was discovered in 2019 by ALMA radio telescope and it
is invisible in ordinary light. When the universe was only 1.2 billion years old. It was a massive
galaxy, It is estimated to have 100 billion stars, about our Milky way Galaxy. Early galaxies
seem to be embedded in a dark matter halo. (Photo is an artist impression.)
29. The Possible Fate of the Universe
Accelerating
Expansion
Constant
Expansion
Slowing down
Expansion
30. Discovery of Dark Energy
Constance
expansion
Accelerating
expansion
Above is the results of observations showing accelerating expansion of the universe. Since we do not know
what cause the accelerating expansion, we called the force behind the expansion as Dark Energy.
31. The Likely Fate of the Universe
The above chart summarized the history of the universe and its development.
Present Day
34. Universe Structure - Galaxy Filament (Web)
This is a simulated image of the Galaxy Filament or Web. Sometimes also called Void and
Filament. Each dot in the picture represent a galaxy.
35. Virgo Galaxy Supercluster
Our Milky Way together with the Local Group is outlying member of the Virgo Supercluster.
The Virgo supercluster is 54 million light-years from us. It contains about 2000 galaxies.
M86
M87
36. Perseus cluster
The Perseus Cluster is about 235 million light-years away. It contains less than 1000 galaxies.
37. Types of Galaxy and Size Comparison
Galaxy varies in size but come in two main shapes – Spiral and Elliptical.
38. Stellar Systems – Stars and Planets
Diagram showing the inner planets of our Solar System, compare with Kepler 52 stellar system.
39. All rights reserved. Rights belong to their respective owners.
Available free for non-commercial and personal use.
The End
Music – Meditation by Messenet
The Hubble telescope has taken us on a journey to the edge of the universe in the last 30 years.
This slideshow explains how scientists measured the size of the universe and its age, It is a miracle that this can even possible to do. The slide show also explain the discovery of the Redshift and the expanding universe. The evolution, the history and the major structure of our universe. It is only within our lifetime, these sorts of question about our origin was asked.