Chapter 10 Section 10.1 - Explaining the Early Universe

Astronomers

People who study objects in space.

This instrument first detected background radiation in the 1960s: ______

radio telescope

Fred Hoyle

A British astronomer who sarcastically nicknamed Lemaitre's theory "the Big Bang".

Electromagnetic Radiation

(Visible light) Energy that is carried, or radiated, in the form of waves. Other types of electromagnetic radiation include microwaves, radio waves and X-rays.

Name four types of electromagnetic radiation.

Visible light Microwaves Radio waves X-rays

State the main idea of the Big Bang theory.

13.7 billion years ago, a very tiny volume of space suddenly rapidly grew in great size. In little time, the universe formed.

Celestial bodies

A general term for all the objects in the sky, including the Sun, Moon, planets, and stars.

Sun

A star - one of the billions of stars that make up the Milky Way.

What characteristics do all galaxies share?

All galaxies share these characteristics, stars, a black hole in the center, Planets, hydrogen and helium and other gases.

Galaxy

An enormous collection of gases, dust, and billions of stars all held together by gravity.

Star

An object in space, with a spherical shape. Its core is like a furnace, which means that it makes its own thermal energy. Every single star you see is part of the Milky Way.

Spectroscope

An optical instrument that acts like a prism to separate light into its basic component colors. A spectroscope allows the user to view the spectral lines produced by a light source to measure their wavelengths.

______ are people who study objects in space.

Astronomers

Both the COBE satellite and WMAP were designed to measure temperatures only a few degrees above absolute zero. Why was it necessary to take these measurements in space rather than from Earth?

Because in earth it would change it.

The theory that suggests that 13.7 billion years ago a tiny volume of space suddenly and rapidly expanded to an immense size is the ______ theory.

Big Bang

How does the pattern shown in the WMAP map indicate that the presence of microwave radiation in the universe is not the same everywhere?

Blue showed denser regions where galaxies formed by gravity. Red shows less dense regions that become less as universe expands.

______ is a general term for all the objects in space, including the Sun, other stars, planets, and the Moon.

Celestial bodies

COBE

Cosmic Background Explorer

What did Edwin Hubble notice about the direction of movement of galaxies in space?

That the distances between galaxies increases as the universe expands.

What do we call radiation that is carried in the form of waves?

EMR: Electromagnetic radiation

Radiation

Energy transmitted in waves that can be picked up from every part of space.

True or False: According to the Big Bang theory, the universe began 17.3 billion years ago.

False. According to the Big Bang theory, the universe began 13.7 billion years ago.

True or False: According to the Big Bang theory, when the universe began it was small, dense, and extremely cold.

False. According to the Big Bang theory, when the universe began it was small, dense, and extremely hot.

True or False: Background radiation is transmitted in waves that were first detected by a spectroscope in the 1960s.

False. Background radiation is transmitted in waves that were first detected by a radio telescope in the 1960s.

True or False: If a star is moving toward you, there is a red shift, which means its wavelengths get longer.

False. If a star is moving away from you, there is a red shift, which means its wavelengths get longer.

True or False: The Big Bang theory has now been proven to be true.

False. The Big Bang is a theory that astronomers have proposed.

True or False: The distance between stars and galaxies of the universe is decreasing.

False. The distance between stars and galaxies is increasing.

True or False: The universe appears to be compressing because galaxies and stars are moving toward each other.

False. The universe appears to be expanding because galaxies and stars are moving away from each other.

______ are moving away from each other. In other words, the universe appears to be expanding.

Galaxies

Why is cosmic background radiation important in the study of the formation of galaxies?

Gave out a greater understanding about universe's early moments.

What conclusion did Hubble make when he observed that distant galaxies appeared to be moving away from each other?

He concluded that the universe itself was expanding so in other words growing; he also used the Hubble law, which is an empirical law. Hubble discovered a relationship between two measurable properties of galaxies: their velocities and their distances.

What did Edwin Hubble discover about the spectra of the galaxies he observed?

He discovered that the farther away galaxies are, the faster they move away.

What evidence did Edwin Hubble use to suggest the universe was expanding?

He used the red shift for his evidence, and the spectrum lines.

How is a loaf of raisin bread baking in the oven a simple model of Hubble's view of an expanding universe?

In bread of raisins, the bread is like the universe, and raisins are like the galaxies. As universe(bread) expands, the farther away the galaxies(raisins) move away from each other.

How does cosmic background radiation provide evidence for the Big Bang theory of the origin of the universe?

It was the leftover radiation from the big bang expansion.

What does the cosmological red shift suggest about the motion of galaxies?

Optical instrument that separates light into basic colour components.

Hubble Space Telescope

Optical telescope sent into space April 1990 from the space shuttle Discovery. Mission expected to last 20 years. Sends back to earth about 120 gigabytes of scientific data every week.

Georges Lemaitre

Proposed the theory that the universe formed in a single, dramatic moment of expansion. Approximately 13.7 billion years ago an unimaginably tiny volume of space suddenly and rapidly expanded to immense size. In a very short time, all the matter and energy in the universe was formed. The catastrophic even, first described by the Belgian priest and physicist Georges Lemaitre in 1927 is known as the Big Bang Theory.

______ is energy that is transmitted in the form of waves.

Radiation

Red Shift

Spectral lines shift towards the red end because the light's wavelengths are becoming longer. Red shifting indicates that an object is receding from us (moving away from us).

Astronomer Edwin Hubble

The first astronomer to identify other galaxies besides the Milky Way. Discovered that all galaxies in space are moving away from each other. By 1929 he estimated the distance from Earth to 46 galaxies.

Spectral Lines

The lines standing out across the bands of color in a star's spectrum. These lines are created by the elements in a star.

State the main idea of the Big Bang Theory.

The main idea of the big bang theory is that all the matter of the universe was concentrated into one point, which then exploded. Evidence, which supports the theory, is that the universe is in fact still expanding, as confirmed by the red shifting of the stars.

What is the purpose of a spectroscope?

The purpose of a spectroscope is to mark different wavelengths of light. Spectroscopes or spectrometers are used to examine the amounts and forms of spectral light that gets into objects such as stars.

How do the raisins in the dough model an expanding universe?

The raisins in the uncooked bread dough all move away from each other as the bread bakes. In a similar way, galaxies in the universe are moving away from each other as the universe expands.

According to the Big Bang theory, how did the temperature of the universe change as the universe expanded?

The red show the areas of slightly hotter temperatures that occurred after big bang event. Blue areas show areas where universe started to cool after big bang event.

Big Bang Theory

The universe is believed to have begun during an unimaginably rapid expansion of a tiny volume of space about 13.7 billion years ago. Evidence for the Big Bang Theory includes observations that show the universe is expanding and the presence of microwave radiation that exists throughout space.

Cosmological Red Shift

The wavelengths of radiated light are being constantly stretched (lengthened) as the light crosses an expanding universe. Cosmological red shift is the main evidence for a theory that explained the formation of the early universe.

Give one piece of evidence that supports the Big Bang theory.

When two american scientists experimented microwave radiation in space, and always had sound interference no matter what method they tried to make that stop. They detected background radiation.

Spectrum

When white light shines through a prism, the light separates into a pattern of colors called a spectrum. Each color of the spectrum represents different wavelengths.

WMAP

Wilkinson Microwave Anistropy Probe

If a star is moving toward you, its wavelengths become ______.

compressed

The term is used when ______ wavelengths of a star become longer as it moves away from you.

red shift

Background radiation has been mapped by ______.

space probes

An instrument that can separate white light into its wavelengths of colour is the ______.

spectroscope