A planet is born

Question 1

What is a planet?

Answer 1

It is a massive object orbiting a star, like the sun. They don’t give off their own light but reflects the suns light.

Question 2

What is the solar system?

Answer 2

It is the sun and all objects that are bound by gravitational force to the sun. This gravitational force of the sun keeps the solar system together just as gravity keeps in the moon in orbit around earth. It includes 8 major planets, their moons and a large number of smaller objects (dwarf planets, asteroids, comets, etc)

Question 3

How is the solar system divided?

Answer 3

It is divided into two parts
1. Inner planets - Mercury, Venus, Earth and mars
2. Outer planets - Jupiter, Saturn, Uranus and Neptune.

Question 4

What is gravity?

Answer 4

It is the force of attraction between all objects. On earth is it 9.8N/kg, on the moon is it 1.6 N/kg. This means that your weight on the moon would be 1/6th of your current weight. This is because the mass of the moon is less, hence it creates lesser gravitational force.

Question 5

What does the law of universal gravitation state?

Answer 5

It explains how the strength of the force depends on the mass of the objects and the distance between them. Mass and gravitational force are directly proportional. Whereas distance and gravitational force are inversely proportional, because the lesser distance between two objects the more force.

Question 6

What is an orbit?

Answer 6

An orbit is a regular, repeating path that an object in space follows around another object. A object in orbit is called a satellite.

Question 7

What is a satellite?

Answer 7

It is a object in orbit. It can be natural like the moon or artificial like the international space station.

Question 8

How does a orbit stay in place?

Answer 8

An orbit results from the balance between intertia and gravitational force. Due to intertia, the planets are moving in a direction at a right angle to the pulling force of gravity.

Question 8

How does a orbit stay in place?

Answer 8

An orbit results from the balance between intertia and gravitational force. Due to intertia, the planets are moving in a direction at a right angle to the pulling force of gravity.

Question 9

What is the shape of a orbit?

Answer 9

It is slightly elliptical

Question 10

What us a axis?

Answer 10

It is the imaginary line that passes through the center of the Earth from pole to pole.

Question 11

What is rotation

Answer 11

Spinning of a planet on its axis. Earth and many other planets spin from east to west.

Question 12

How are years are revolutions connected?

Answer 12

All of the planets orbit, or revolve, around the Sun in the same direction (counter-clockwise). A year is a time it takes a planet to complete one revolution around the Sun. A year on Earth takes approximately 365.25 days. A year on Mars takes 686.98 Earth days. The farther a planet is from the Sun, the longer it takes it to complete one revolution. One year on Neptune, the outermost planet is 164.81 Earth years long

Question 13

Size of objects in the solar system

Answer 13

The Sun is by far the largest object in the solar system. The next largest objects are the planets Jupiter, Saturn, Uranus, and Neptune. the planets Mercury, Venus, Earth, and Mars appear as small dots compared with the size of the Sun.

Question 14

Distance from the sun, and between objects in the solar system

Answer 14

Astronomers often use the distance of Earth from the Sun as a measurement of distance in the solar system. One astronomical unit (AU) is equal to 150 million kilometers, or the distance from Earth to the Sun. Mercury is 58 million kilometers from the Sun. To convert this distance to astronomical units, divide it by 150 million kilometers (or divide 58 by 150). Mercury is 0.39 AU from the Sun.

Question 15

How are planets classified?

Answer 15

The planets are commonly classified in two groups. 1. The terrestrial planets include Mercury, Venus, Earth, and Mars. The terrestrial planets are mostly made of rock and metal. They have relatively: high densities, slow rotations, solid surfaces, and few moons.
2. The gas giants, include Jupiter, Saturn, Uranus, and Neptune. They are made mostly of hydrogen and helium. These planets have relatively low densities, rapid rotations, thick atmospheres, and many moons.

Question 16

What are dwarf planets?

Answer 16

A dwarf planet cannot clear objects out of its orbit because it is too small in mass to significantly alter its environment. For example, Pluto overlaps the orbit of Neptune, which disqualifies it as a planet.

Question 17

3 common dwarf planets

Answer 17

Some dwarf planets include
∙ Pluto, which is located among the Kuiper (rhymes with “viper”) Belt Objects (KBOs);
∙ Ceres, which is located in the asteroid belt between Mars and Jupiter and;
∙ Eris, which is a Scattered Disc Object (SDO).

Question 18

What is the sun?

Answer 18

The Sun is a star. A star is a giant, hot ball of gas held together by gravity. Gravity squeezes the atoms of hydrogen in the core of a star so tightly that they fuse together in a reaction called nuclear fusion producing helium.

Question 19

What is the sun made of?

Answer 19

The Sun is about 75 percent hydrogen and 25 percent helium, with very small traces of other elements. Unlike Earth, the Sun does not have a solid surface—instead, it is made completely of gas.

Question 20

How does the suns mass affect the solar system?

Answer 20

Because of its size, the Sun contains 99.8 percent of the mass of the solar system. Because of its mass, the Sun’s gravitational force is strong enough to hold the entire solar system—including the planets, dwarf planets, asteroids, and comets—in orbit.

Question 21

The layers of the sun

Answer 21

The apparent surface of the Sun that we can see from a distance is called the photosphere, which means “sphere of light.” Just above it is the chromosphere. This is a very hot layer of plasma, a high-energy state of gas. The corona is the outermost layer of the Sun’s atmosphere, extending millions of kilometers outward.
1. Core - Nuclear fission
2. Radiation zone - Heat transfer mainly through light
3. Convection zone - Heat transfer through motion of hot gas
4. Photosphere - Visible surface
5. Chromosphere - Inner atmosphere
6. Corona - Outer atmosphere.

Question 22

What is a sunspot?

Answer 22

an area of gas on the Sun that is cooler than the gases around it; sunspots appear as dark spots on the Sun’s photosphere

Question 23

What are the features of the sun?

Answer 23

1. Sometimes prominences from different sunspot regions suddenly connect, releasing very large amounts of heat and light known as solar flares.
2. The Sun gives off more than just heat and light. It also gives off something called solar wind. Solar wind is an electrically-charged mixture of protons and electrons.
3. Solar flares can greatly increase the amount of solar wind given off by the Sun. These solar wind particles can affect Earth’s upper atmosphere, causing magnetic storms.
4. Solar winds sometimes cause a mysterious phenomenon known as an aurora to occur. Auroras (known in the Northern Hemisphere as the northern lights) occur when gases in our upper atmosphere are energized by solar wind particles.

Question 24

How are stars and fusion related?

Answer 24

1. Stars generate light and heat through nuclear fusion. Specifically, they are powered by the fusion of hydrogen under conditions of enormous temperature, mass, and density. When hydrogen atoms fuse, helium is created.
2. The conditions required for the continuous fusion of hydrogen are extremely high temperature, density, and pressure. These conditions are found when the mass of hydrogen is very large.
3. Even though stars are made of gas, they have extremely high values for density and mass. For example, the density of the Sun’s core is about 158.0 g/cm3. This is about 18 times the density of copper.

Question 25

What is a constellation?

Answer 25

a group of stars that, when seen from Earth, form a pattern.

Question 26

What is the big bang theory?

Answer 26

The Big Bang theory says the universe began as a huge explosion between 10 billion and 20 billion years ago. According to this theory, all matter and energy started in a space smaller than the nucleus of an atom. Suddenly, a huge explosion occurred that sent everything that makes up the universe out in all directions. Immediately after the explosion, the universe began to expand, cool, and slow down. After a few minutes, hydrogen nuclei began forming. Next, hydrogen nuclei began fusing to form helium nuclei. Because atoms were still flying around with high energy, heavy nuclei were smashed apart. For the next 700,000 years, the universe was like the inside of a star: hot hydrogen and helium. The universe had expanded enough to become transparent to light. When the universe was about 1 billion years old, it had expanded and cooled enough that galaxies and stars could form. At this point, the universe probably began to look similar to how it looks today. The Sun and solar system formed about 4.6 billion years ago, by which time the universe was about 12 billion years old.

Question 27

What is the evidence for the big bang theory?

Answer 27

1. The fact that galaxies are expanding away from each other is a strong argument for the Big Bang. As far as we can look into the universe, we find galaxies are expanding away from each other.
2. When you light a match, the flame bursts rapidly from the first spark and then cools as it expands. When the Big Bang exploded, it also created hot radiation. This radiation has been expanding and cooling for 16 billion years.
3. The proportion of hydrogen to helium is consistent with the physics of the Big Bang (Figure 19.27). Elements heavier than hydrogen and helium are formed in stars. When stars reach the end of their life cycles, they spread heavy elements such as carbon, oxygen, and iron out into the universe.

Question 28

What is the nebular hypothesis?

Answer 28

The nebular hypothesis states that a giant cloud of just and gas called the nebula collapsed to form the solar system

Question 29

What was the solar nebula?

Answer 29

The sun and the planets formed a giant cloud of dust and gas. This was the solar nebula. The cloud contracted and began to spin. As it contracted the temperature and pressure increased and the cloud spun faster to become a disk.

Question 30

How did the material at the center of the solar system become a star?

Answer 30

Temperatures and pressure are the center of the cloud was extreme, so extreme that nuclear fission occurred to create the sun. The outer parts of the disc were cooling off and dust started clumping together. Gravity made the bodies larger. Gravity at the center attracted rock and metal, lighter material was remained farther out in the disk. Eventually the bodies grew to become planets and moons.