Early Space Exploration Assignment (2)

.docx

School

Plymouth State University *

*We aren’t endorsed by this school

Course

2930

Subject

Astronomy

Date

Jan 9, 2024

Type

docx

Pages

8

Uploaded by SuperHumanDog3821

Report
Name: _______________________________________ Date: ___________________________ Lesson 23.1: Early Space Exploration CK-12 Assignment (50 points) True or False Write true if the statement is true or false if the statement is false. Put a “T” for a true statement and a “F” for a false statement. __T___ 1. The first rockets ever used were launched in the 20th century. __T___ 2. The first liquid-fuel rockets to be built were designed by Robert Goddard. __T___ 3. Wernher von Braun joined NASA and helped design rockets for space travel. _F____ 4. The first satellite ever to orbit Earth was put into space by the United States. _F____ 5. The scientist who first explained how satellites stay in orbit was Hermann Oberth. __T___ 6. Over the past 50 years, thousands of artificial satellites have been put into orbit around Earth. ___T__ 7. The speed of a satellite depends on how high it is above the object it is orbiting. __T___ 8. U.S. Mariner missions sent space probes to the outer solar system. _F____ 9. U.S. Voyager probes are now traveling toward the sun. T_____ 10. The U.S.S.R. sent probes to Venus and landed some of them on the surface. Lesson 23.2: Critical Reading Read this passage based on the text and answer the questions that follow. Types of Satellites and Their Orbits Since the first artificial Earth satellite was launched more than 50 years ago, thousands of artificial satellites have been put into orbit around our planet. We have even put satellites into orbit around the Moon, the Sun, and several other planets. Depending on their purpose, there are four main types of satellites: imaging satellites, communications satellites, navigational satellites, and the International Space Station. Imaging satellites take pictures of Earth’s surface that are used for military or scientific purposes. For example, meteorologists use imaging satellites to study Earth’s weather. Astronomers use them to study the Moon and other planets. Communications satellites are designed to receive and send signals for telephone, television, or other types of communications.
Navigational satellites are used for navigation systems, such as the Global Positioning System (GPS). The International Space Station (ISS), the largest artificial satellite, allows humans to live in space while conducting scientific research. The speed of a satellite depends on how high it is above Earth’s surface. Satellites that are relatively close to Earth are said to be in low-Earth orbit (LEO). Satellites in LEO are often in polar orbit. This means that they travel over the North and South Poles and move in a direction that is perpendicular to the direction of Earth’s rotation. Because Earth rotates beneath a polar-orbit satellite, the satellite is over a different part of Earth’s surface each time it circles the planet. Imaging satellites and weather satellites are often put in low-Earth, polar orbits. A satellite placed at just the right distance above Earth—35,786 km (22,240 miles)—orbits Earth at the same rate of speed that Earth spins on its axis. When such a satellite orbits Earth in the same direction as Earth’s rotation, it is always over the same position on Earth’s surface. This type of orbit is called a geostationary orbit (GEO). Many communications satellites are in geostationary orbits. Questions 1. Identify four main types of satellites based on their purpose . Answer: Satellites can be categorized into four main types based on their purpose: 1. **Communication Satellites**: These satellites are designed for transmitting and receiving data, including television signals, internet connectivity, and telephone communication. They are often placed in geostationary orbits (GEO) to maintain a fixed position relative to the Earth's surface for consistent communication coverage. 2. **Earth Observation Satellites**: These satellites are used to observe and monitor the Earth's surface, atmosphere, and oceans. They provide valuable data for applications like weather forecasting, environmental monitoring, agriculture, and disaster management. Earth observation satellites can be in various orbits, including polar and sun-synchronous orbits. 3. **Navigation Satellites**: Navigation satellites, such as those in the Global Positioning System (GPS), provide precise positioning and timing information to users on the Earth's surface. They are usually in medium Earth orbits (MEO) and are essential for applications like navigation, mapping, and location-based services. 4. **Scientific and Space Exploration Satellites**: These satellites are used for scientific research, space exploration, and astrophysical observations. They include telescopes like the Hubble Space Telescope, planetary probes, and observatories studying phenomena in space. Their orbits and configurations vary depending on their specific missions and objectives.
These are just a few examples of the many satellite types that serve various purposes, including military and defense satellites, space debris monitoring satellites, and more. Each type of satellite is designed to fulfill specific functions and contribute to a wide range of applications and industries. 2. Describe a polar orbit, and explain why a satellite in a polar orbit is over a different part of Earth’s surface each time it circles the planet. Answer: A polar orbit is a type of satellite orbit that takes the satellite over the Earth's poles on each orbit. In this orbit, the satellite travels from the North Pole to the South Pole and back on each revolution around the Earth. The key characteristics of a polar orbit are as follows: 1. **Inclination**: Polar orbits have a high inclination, which means the orbit is tilted relative to the Earth's equator. The inclination is typically close to 90 degrees, and the satellite passes directly over the poles. 2. **Low Altitude**: Polar orbits are often at relatively low altitudes, typically in the Low Earth Orbit (LEO) range, which can be a few hundred to a couple of thousand kilometers above the Earth's surface. The reason a satellite in a polar orbit passes over a different part of Earth's surface each time it circles the planet is due to the rotation of the Earth itself. The Earth rotates on its axis from west to east. Here's how it works: 1. **Earth's Rotation**: While the satellite is in orbit, the Earth continues to rotate underneath it. This means that with each orbit, the satellite is effectively "chasing" the rotation of the Earth. 2. **Coverage**: Since the Earth rotates 360 degrees every 24 hours, and a polar orbiting satellite completes an orbit in less time, the Earth has rotated a certain amount by the time the satellite completes one orbit. As a result, the satellite's ground track shifts slightly to the west with each orbit.
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
  • Access to all documents
  • Unlimited textbook solutions
  • 24/7 expert homework help