Earth’s Moon

&

Traveling Into Space

Chapter 15 S4 and S5

Chapter 15 Essential Questions S4

1. What features are found on the moon’s surface?

2. What are some characteristics of the moon?

3. How did the moon form?

Chapter 15 Essential Questions S5

What is the difference in a space shuttle, space station, and a space probe?

*A telescope makes faraway objects appear closer.

Features on the moon’s surface include maria, craters, and highlands.

Moon’s Surface

• The moon’s surface has dark, flat areas called maria (MAH ree uh). Maria are flat areas of hardened rock.

• Craters are large, round pits on the moon. Craters were caused when meteoroids crashed into the moon. A meteoroid is a chunk of rock or dust from space.

• Highlands are mountains that cover most of the moon’s surface.

highland

maria

craters

The Moon’s Surface

Mare Tranquillitatus(Sea of Tranquility)

Mare Imbrium(Sea of Rains)

KeplerCrater

CopernicusCrater

Major Topographic Features of the Moon

Formation of a Crater

Characteristics of the Moon

• The moon is dry and airless. Compared to Earth, the moon is small and has large variations in its surface temperature.

• There is no air on the moon. The moon has no atmosphere.

• The moon is about one-fourth the diameter of Earth.

• Temperatures on the moon range from very hot to very cold.

• The moon has no liquid water.

The Origin of the Moon

• Scientists theorize that a planet-sized object collided with Earth to form the moon.

• Very long ago, big rocks were moving around in space.

• Scientists think that one of these big rocks may have crashed into Earth. Material from Earth broke off. The broken off portion of Earth became the moon.

Formation of Earth’s Moon

video

Traveling into Space (S5)

• Rocket technology originated in China hundreds of years ago. Modern rockets were first developed about a century ago.

• A rocket is a device that sends gas in one direction to move in the opposite direction. A rocket sends gas out the back, causing the rocket to move forward.

The Race for Space

• The rivalry between the United States and the Soviet Union over the exploration of space was known as the “space race.”

• In the 1950s, the United States and the Soviet Union (now Russia) began to compete in the exploration of space.

• The space race began in 1957 when the Soviets launched the satellite Sputnik I into orbit. The United States responded by speeding up its own space program.

• A satellite is an object that revolves around another object in space. The moon is a natural satellite. A spacecraft orbiting Earth is an artificial satellite. “Artificial” means it is made by people.

Satellite

• In 1957, the Soviet Union launched a satellite into space. The satellite was called Sputnik I. In 1958, the United States launched a satellite called Explorer I.

• The Soviet Union launched the first human into space in 1961. His name was Yuri Gagarin. The first American launched into space was Alan Shepard later in 1961. The first American to orbit Earth was John Glenn in 1962.

Missions to the Moon • The American effort to land

astronauts on the moon was named the Apollo program.

• In 1969, U.S. astronaut Neil Armstrong became the first person to step on the moon. Armstrong and another astronaut named Buzz Aldrin explored the moon. Their flight to the moon was aboard the spacecraft Apollo II.

Exploring Space Today

• NASA has used space shuttles to perform many important tasks. These include taking satellites into orbit, repairing damaged satellites, and carrying astronauts and equipment to and from space stations. A space station provides a place where long-term observations and experiments can be carried out in space.

• A space shuttle is a spacecraft that can carry people into space. A space shuttle can then return to Earth and land like an airplane. A space shuttle can be used many times.

• A space station is a large satellite where people can live and work. The International Space Station is in orbit around Earth.

Station shuttle

• Space probes gather data about distant parts of the solar system where humans cannot easily travel.

• A space probe is a spacecraft that carries scientific instruments into space. The instruments collect information. No humans are on board a space probe.

• Some space probes land on other planets. Some space probes fly around other planets.

probes

• Some space probes have small robots called rovers. Rovers move around on the surface of a planet and collect information.

• Space probes have been sent to all planets.

rovers

Chapter 15 Essential Questions S41. What features are found on the moon’s

surface?craters, maria, and highlands2. What are some characteristics of the

moon?No air, no atmosphere, temp ranges from

very hot to very cold, no liquid water, and is about one-fourth the diameter of Earth

3. How did the moon form?Scientists think that a planet-sized object

collided with the Earth to form the moon.

Chapter 15 Essential Questions S5

What is the difference in a space shuttle, space station, and a space probe?

Space shuttle can carry people into space.

Space station is where people can live in work in space.

Space probe carries scientific instruments into space.