EARLY UNIVERSEBy: Andrew Cheung

Teacher: Mr. Horton

Edwin Powell Hubble• Born on November 20, 1889 Marshfield, Missouri• Died on September 28, 1953 San Marino, California

• He was an astronomer who played a crucial role in establishing the field of extragalactic astronomy.

• He is known for showing that the recessional velocity* of a galaxy increases with its distance from earth, which means the Universe is still expanding. This is known as “Hubble's law”

• He is also known for the Hubble sequence, the most commonly used system for classifying galaxies, grouping them by their appearance.

*The rate at which an object is moving away, typically from Earth

Edwin Hubble

Hubble sequence

Technological Help• 100 years ago, astronomers said that anything in outer space never

changes, thats because they did not have the technology we have today

• From 1918 to 1929, we started to develop much more powerful telescopes and we were able to see more celestial bodies* then what we have ever seen.

• With this new technology, Edwin Hubble estimated the distance between earth and 46 different galaxies, then he noticed that the galaxies were not staying still, but they were actually moving away from each other.

• Without this technology, we would have never found out that galaxies actually moves away from each other.

* Any natural body outside of earth’s atmosphere. Ex. Moon, Sun

Hubble's Proposal• To expand on the idea of the galaxies moving away from each other,

Hubble retraced the paths which galaxies would likely have crossed, he found that they had all started moving from the same place in space.

• Knowing this, he proposed that the universe is expanding in all directions. He also proposed that all the galaxies have taken the same amount of time to get to their current position.

• He used the Red Shift Analysis to figure out the galaxies were moving away from earth, and that the speed was proportional to their distance.

Electromagnetic waves• Visible light is one type of electromagnetic radiation.

• Electromagnetic radiation that is carried in the form of waves.

• Other types of electromagnetic waves are microwaves, radio waves, X rays, ultraviolet radiation, infrared, and gamma rays.

Spectral Patterns• White light splits into the colors of the rainbow when it is passed

through a prism. Examples of white light are the sun and a lamp.

• This certain pattern of colors is called a spectrum.

• Light from stars can be collected by astronomers then changed into a spectral pattern. Buy using a spectroscope* the user can measure the wavelengths of a light source.

*An instrument used to measure properties of light over a specific portion of the electromagnetic spectrum.

White light going though a prism, creating the spectrum

Cosmological red shift• Light that is from a distant galaxy travels a huge distance before our

observers on earth can even see them with a telescope.

• Edwin Hubble noticed that the spectral lines from the light of galaxies he was studying were shifted toward the red. This is called red shift.

• Red shift occurs because the wavelengths of the light are becoming longer. Red-shifting indicates that an object is moving away. Which means the galaxies are moving away from us.

• Astronomers put forward the idea that space itself is expanding. Which is why the wavelengths are being constantly lengthened. This is the cosmological red shift.

A Redshift

The Big Bang Theory• Hubble’s observations of galaxies moving away from each other led

astronomers to trace the paths of the galaxies back to their origin. They found that in a certain point in time, all these galaxies might have all been in the same place, at the same time. The search for an explanation has been going on for a long time.

• The most supported theory is the Big Bang Theory: Approximately 13.7 billion years a tiny volume of space suddenly expanded to an immense size in a very short time, all the matter and energy in the universe was formed. (first described by Georges Lemaître in 1927)

https://www.youtube.com/watch?v=VOz4PkdY7aA&app=desktop

Georges Henri Joseph Édouard Lemaître

• Born on July 17, 1894 Charleroi, Belgium• Died on June 20, 1966 Leuven, Belgium• Was a Belgian priest, astronomer and professor of physics at the

Catholic University of Leuven.

• He proposed what is known as the Big Bang theory, which he called his “hypothesis of the primeval atom” or the “Cosmic Egg”

Georges Lemaître

Cosmic background radiation• 35 years after Lemaître made his theory, two American astronomers,

Arno Penzias and Robert Wilson discovered one of the most important pieces of evidence that Big Bang theory is true.

• In 1963, they were monitoring microwave radiation in space. They kept receiving background “noise, or signal interference. They originally thought that the problems were caused by faulty equipment. However, after they changed equipment, they kept picking up interference. They concluded that what they were detecting was “cosmic background radiation.”

• Most scientists believe that is the radiation left from the Big Bang. As particles of gas from the early universe were in the form of microwave radiation.

Arno Allan Penzias• Born on April 26, 1933 (age 81) Munich, Germany

• An American physicist, radio astronomer and Nobel laureate in physics.

• He is the co-discoverer (along with Robert Wilson) of cosmic microwave background radiation, which helped support the Big Bang theory.

Arno Penzias

Robert Woodrow Wilson• Born on January 10, 1936 Houston, Texas

• An American astronomer, 1978 Nobel laureate in physics.

• He is the co-discoverer(along with Arno Penzias) of cosmic microwave background radiation.

Robert Wilson

Cosmic Background Explorer (COBE)

• Launch date: November 18, 1989 Valdenberg Air Force Base, Launched by NASA

• Its goals were to investigate the cosmic background radiation of the universe and to provide measurements that would help our understanding of the cosmos.

• After 4 years of mapping, scientists made the map on how the universe might have looked like in its early stages. Red meaning areas with hotter temperatures, and blue meaning areas with cooler temperatures, which means the universe was cooling. This evidence supports the Big Bang theory.

Wilkinson Microwave Anisotropy Probe (WMAP)

• Launch date: June 30 2001, Cape Canaveral Air Force Station, launched by NASA

• It was able to make more precise measurements then ever before. The microwave radiation data is on the map. Blue is denser regions of the early universe, Red is the less dense regions that have became emptier and emptier as the universe expanded. These results confirmed the data collected by COBE.

The WMAP Data

Conseil Européen pour la Recherche Nucléaire(CERN)• Also known as The European Organization for nuclear

Research in English• Established on September 29, 1954• There are currently 21 countries in CERN

• CERN’s main function is to provide the particle accelerators and other infrastructure needed for high-energy physics research.

CERN logo

Hubble Space Telescope• Launched on April 21, 1990 John F. Kennedy Space

Center, Launched by NASA

• Hubble is a space telescope that was launched into low earth orbit in 1990, and remains in operation. With a 7.9 ft mirror. It is named after the famous astronomer Edwin Hubble, who greatly influenced extragalactic astronomy.

Hubble Space Telescope

Its images have led to breakthroughs in astrophysics, such as accurately determining the rate of the expansion of the universe.