A fun and interesting overview of the living conditions for astronauts in space. This book is at a reading level of 3.6 with a word count of 1121.
An overview of the different characteristics of the Earth that make it unique. This book has a reading level of 2.6 and a word count of 604.
An educational look into what is known about outer space and its many wonders. This book has a reading level of 2.6 and a word count of 622.
People once believed that Earth was the center of the solar system. Scientists finally learned that Earth is one of at least eight planets in our solar system and that they all travel around the sun. Astronomers now know that our solar system is almost 5 billion years old and is part of at least 100 billion galaxies in the universe. Earth is the only planet known to have life and water. Scientists continue to discover new planet-like objects, called dwarf planets, all the time!
Ancient astronomers looked at movements in the sun, moon, and stars to guide travelers and keep track of the seasons. Nicholas Copernicus was the first to challenge people's beliefs that Earth was the center of the solar system and is known as the founder of astronomy. Galileo Galilei built a telescope and spotted craters on the moon and sunspots on the sun. Isaac Newton invented the reflecting telescope and discovered the law of gravity. Astronomers continue to work every day to uncover the mysteries of the universe.
Much of what we know today about Earth is from images taken by cameras on powerful telescopes. Edwin Hubble changed our view of the universe. Working in an observatory, he found that there are other galaxies besides the Milky Way. He also showed that the universe is still growing. Lyman Spitzer, Jr. proposed placing telescopes in space, and in 1990, the Hubble Space Telescope was launched. It sends us amazing images of the universe.
Light and sound are two of the most important ways to understand the world around us. The sun is Earth's main source of energy and light. Light bounces off objects and travels to our eyes. Our eyes and brain work together to translate that light into what we see while our ears pick up sound vibrations and translate them into meaningful messages.