Lesson 1: Origin & Structure of the Earth, the Universe and the Solar System

Question 1

“Ordinary” matter consisting of protons, electrons, and neutrons that comprises atoms, planets, stars, galaxies, and other bodies.

Answer 1

Baryonic Matter

Question 2

Matter that has gravity but does not emit light.

Answer 2

dark matter

Question 3

A source of anti-gravity; a force that counteracts gravity and causes the universe to expand.

Answer 3

dark energy

Question 4

An early stage in the formation of a star resulting from the gravitational collapse of gases

Answer 4

Protostar

Question 5

A nuclear fusion reaction responsible for the energy produced by stars

Answer 5

Thermonuclear Reaction

Question 6

Stars that fuse Hydrogen atoms to form Helium atoms in their cores; outward pressure resulting from nuclear fusion is balanced by gravitational forces.

Answer 6

Main Sequence Stars

Question 7

A large unimaginable expanse of gas, stars, dust clouds, and consists of planets and galaxies.

Answer 7

Universe

Question 8

The structure of the universe is composed of:

a) 63.4% - dark energy; 27% - dark matter; 9.6% - Baryonic Matter
b) 71% - dark energy; 24.4% - dark matter; 4.6% - Baryonic Matter
c) 60% - dark energy; 20% - dark matter; 20% - baryonic matter
d) 71.4% - dark energy; 24% - dark matter; 4.6% - Baryonic Matter

Answer 8

d) 71.4% - dark energy; 24%- dark matter; 4.6% - Baryonic Matter

Question 9

What are the three most abundant elements in the universe?

a) Hydrogen, Helium, Beryllium
b) Hydrogen, Helium, Lithium
c) Hydrogen, Lithium, Beryllium
d) Hydrogen, Aluminum, Iron

Answer 9

b) Hydrogen, Helium, Lithium

Question 10

the building block of galaxies and is born out of clouds of gas and dust in galaxies

Answer 10

Stars

Question 11

the hot core of a future star as thermonuclear reactions set in

Answer 11

Protostar

Question 12

It is the contraction of an astronomical object due to the influence of its own gravity. It is a fundamental mechanism for structure formation in the universe.

Answer 12

Gravitational Collapse

Question 13

These are like furnaces where elements are synthesized or combined/fused together. Most stars such as the sun belong to the so called “main sequence stars”. In the cores of such stars, hydrogen atoms are fused through thermonuclear reactions to make helium atoms.

Answer 13

Stellar Interiors

Question 14

A star’s energy comes from combining light elements into heavier elements by fusion, also called ________

Answer 14

Nuclear Burning or Nucleosynthesis

Question 15

What are the four main kinds of galaxies?

Answer 15

Elliptical, Spiral, Irregular, and Barred Spiral

Question 16

Based on recent data, how old is the universe?

Answer 16

Around 13.8 billion years old

Question 17

The diameter of the universe is possibly infinite but should be at least ______________

Answer 17

91 billion light years

Question 18

It is the distance light can travel in a year; a unit of length used to measure astronomical distance

Answer 18

Light Years

Question 19

What is approximately the density of the universe?

Answer 19

4. 5 x 10^-31 g/cm^3 (according to resource book)

9. 9 x 10^-30 g/cm^3 (according to wmap.gsfc.nasa.gov)

Question 20

It is a cluster of billions of stars and clusters of galaxies to form super clusters.

Answer 20

Galaxies

Question 21

It is the currently accepted theory of the origin and evolution of the universe. It postulates that 12 to 14 billion years ago, the portion of the universe we can see today was only a few millimetres across. It has since expanded from this hot dense state into the vast and much cooler cosmos we currently inhabit.

Answer 21

The Big Bang Theory

Question 22

The Big Bang Theory rests on what two main principles?

Answer 22

Theory of General Relativity & the Cosmological Principle

Question 23

__________ assumes that the universe is homogeneous and isotropic.

Answer 23

The Cosmological Principle

Question 24

___________ generalizes Isaac Newton’s theory of gravity; describes gravity no longer as a gravitational “field” but rather it is supposed to be a distortion of space and time itself.

Answer 24

Theory of General Relativity

Question 25

define isotropic

Answer 25

uniformity in all orientations; not varying in magnitude according to the direction of measurement

Question 26

define homogeneous

Answer 26

properties are same on every point

Question 27

Ancient Egyptians believed in many gods and myths which narrate that:

a. the world was spewed by a serpent and gave birth to the stars
b. the world arose from an infinite sea at the first rising of the sun
c. the God Isis created the world from a big mold of mud and formed with it the sky and the seas
d. the Egyptians believed no myth about how the world formed

Answer 27

b. the world arose from an infinite sea at the first rising of the sun

Question 28

The ______________ tell the story of a creator God _______ who, alone in a dark and water-covered earth, felt an intense stomach pain and then vomited the stars, sun and moon.

Answer 28

Kuba people of Central Africa; Mbombo (or Bumba)

Question 29

In India, there is the narrative that Gods sacrificed ________, the primal man whose head, feet, eyes, and mind became the sky, earth, sun, and moon respectively.

Answer 29

Purusha

Question 30

It is an alternative theory of the origin of the universe, first put forward by Sir James Jean in about 1920 then revised by Bondi and Gould in 1948, then it as further developed by Fred Hoyle to deal with problems that had arisen in connection with alternative big bang hypothesis.

Answer 30

Steady State Model

Question 31

It is a view that the universe is always expanding but maintaining a constant average density, matter being continuously created to form new stars and galaxies at the same rate that old ones become unobservable as a consequence of their increasing distance and velocity of recession.

Answer 31

Steady State Model

Question 32

This theory maintains that new matter is created as the universe expands thereby maintaining its density.

Answer 32

Steady State Model

Question 33

A hypothetical scenario for the ultimate fate of the universe, in which the expansion of the universe eventually reverses and the universe recollapses, ultimately causing the cosmic scale factor to reach zero, an event potentially followed by the reformation of the unvierse.

Answer 33

Big Crunch

Question 34

It can be observed as a strikingly uniform faint glow in the microwave bond coming from all directions - black body radiation with an average temperature of about 2.7 degrees above absolute zero. This was accidentally discovered by Arno Penzias and Robert Woodrow Willson in 1964.

Answer 34

Cosmic Microwave Background Radiation

Question 35

What is the temperature absolute zero?

Answer 35

-273.15 degrees C / -459.67 degrees F

Question 36

The universe is expanding for a time and then to its contradiction due to gravity.

Answer 36

Oscillating Theory

Question 37

What tests has the Big Bang Theory withstood for it to become the broadly accepted theory of how the universe began?

Answer 37

1) The Red Shift
2) It proves the abundance of hydrogen, helium, and lithium.
3) The uniformly pervasive cosmic microwave background radiation

Question 38

It explains the peculiarities of the orbit of Mercury and the bending of light by the sun.

Answer 38

Theory of General Relativity

Question 39

What are the main theories on how the universe will meet its end?

Answer 39

The Big Crunch / The Big Rip / The Big Freeze or The Big Chill

Question 40

Nucleosynthesis requires very high temperature. What is the minimum temperature for H fusion?

Answer 40

5 x 10^6 degrees Celcius

Question 41

What would be the fate of the universe if the density of the universe is lower than the critical density?

Answer 41

There wouldn’t be enough gravitational force to stop or reverse the expansion — the universe would expand to the “Big Chill or the Big Freeze” since it cools down during the expansion.

Question 42

What would be the fate of the universe if the density of the universe is greater than the critical density?

Answer 42

Gravity would eventually stop the expansion of the universe and end with a “Big Crunch” and perhaps to generate into another “bang”.

Question 43

Which of the following would scientists say true about most galaxies?

a) They are moving away from each other.
b) They spread evenly throughout space.
c) They consist only of stars.
d) They are held together by electromagnetism.

Answer 43

a) They are moving away from each other.

Question 44

Globular clusters in our galaxy ___________.

a) are concentrated in the galactic nucleus.
b) are spherically distributed about the galactic center.
c) are present only in our galaxy.
d) are concentrated in spiral arms.

Answer 44

a) are concentrated in the galactic nucleus.

Question 45

The expansions of the universe was discovered by observing that all galaxies are moving away from us. Who made this discovery?

a) Albert Einstein
b) Johannes Kepler
c) Edwin Hubble
d) Both a & c

Answer 45

c) Edwin Hubble.

In 1929, Edwin Hubble announced that he had measured the speed of galaxies at different distances, and had discovered that the farther they were, the faster they were receding.

Question 46

Which of the following would scientists say is true about matter in the universe?

a) Matter in the universe started out very uniform and has gotten less uniform with time.
b) The first elements formed in the universe were primarily hydrogen and helium.
c) All the present structure in the universe was formed in the Big Bang.
d) None of the above.

Answer 46

b) The first elements formed in the universe were primarily hydrogen and helium.