The universe is made up of all kinds of stuff. There are galaxies, stars, planets, comets, black holes, and other objects we can see with our eyes or with the help of telescopes. But there are also lots of other things in space that we cannot see, and we do not know much about this stuff. The objects that scientists have found make up about 5% of all the things in the universe. The rest of the stuff out there is known as dark matter and dark energy.
Dark matter is the name given to objects with gravity that do not reflect the kind of light we can detect with our current technology. Scientists do not know what those objects are, but they know the objects exist because they observe objects they can see cast shadows where no objects appear to be, and they also use the Hubble telescope to watch light bend as it passes through a special kind of lens. Scientists believe dark matter makes up about 27% of the stuff in space.
Dark energy is the other stuff in space that scientists study. Because the universe is still expanding, scientists believe there is some kind of energy making it grow, and they have named it "dark energy." They do not know much about dark energy yet, but they believe it makes up about 67% of all the stuff in space.
Source: NASA SpacePlace
Beyond by
Journey far beyond our solar system and explore the marvels of interstellar space. A wonder-filled poem and spectacular illustrations bring readers across the observable universe to encounter dwarf planets, black holes, brand-new stars, and other incredible phenomena. Award-winning author Miranda Paul and illustrator Sija Hong present a fresh and fascinating journey to the outer reaches of outer space.
Behind the Scenes of the Universe by
An extraordinary discovery has recently shaken the foundations of Cosmology and Particle Physics, sparking a scientific revolution that has profoundly modified our understanding of our Universe and that is still far from over. Pioneering astronomers in the 1920s and 1930s had already noticed suspicious anomalies in the motion of celestial bodies in distant galaxies and clusters of galaxies, but it wasn't until the late 20th century that the scientific community was confronted with an astonishing conclusion: the Universe is filled with an unknown, elusive substance that is fundamentally different from anything we have ever seen with our telescopes or measured in our laboratories. It is called dark matter, and it constitutes one of the most pressing challenges of modern science. In this book, aimed at the general reader with an interest in science, the author illustrates in non-technical terms, borrowing concepts and ideas from other branches of art and literature, the far-reaching implications of this discovery. It has led to a worldwide race to identify the nature of this mysterious form of matter. We may be about to witness a pivotal paradigm shift in Physics, as we set out to test the existence of dark matter particles with a wide array of experiments, including the Large Hadron Collider at CERN, as well as with a new generation of Astroparticle experiments underground and in space.
Three Steps to the Universe by
If scientists can't touch the Sun, how do they know what it's made of? And if we can't see black holes, how can we be confident they exist? Gravitational physicist David Garfinkle and his brother, science fiction writer Richard Garfinkle, tackle these questions and more in Three Steps to the Universe, a tour through some of the most complex phenomena in the cosmos and an accessible exploration of how scientists acquire knowledge about the universe through observation, indirect detection, and theory. The authors begin by inviting readers to step away from the Earth and reconsider our Sun. What we can directly observe of this star is limited to its surface, but with the advent of telescopes and spectroscopy, scientists know more than ever about its physical characteristics, origins, and projected lifetime. From the Sun, the authors journey further out into space to explore black holes. The Garfinkle brothers explain that our understanding of these astronomical oddities began in theory, and growing mathematical and physical evidence has unexpectedly supported it. From black holes, the authors lead us further into the unknown, to the dark matter and energy that pervade our universe, where science teeters on the edge of theory and discovery. Returning from the depths of space, the final section of the book brings the reader back down to Earth for a final look at the practice of science, ending with a practical guide to discerning real science from pseudoscience among the cacophony of print and online scientific sources. Three Steps to the Universe will reward anyone interested in learning more about the universe around us and shows how scientists uncover its mysteries.
Dark Matter Explained by
Scientists believe that the universe is mostly made up of dark matter, a mysterious substance that is different from the ordinary matter people can touch, smell, see, and interact with. Dark matter cannot be directly observed, but it can be studied by examining its effect on ordinary matter. Simplified explanations of complex scientific concepts and fascinating images will help students understand how physicists employ Kepler's laws of planetary motion, gravitational lensing, particle colliders, and other theories and tools to learn about dark matter. Informative sidebars explore related timely topics in depth, while a Further Reading section provides several resources for additional study.
Dark Matter by
Explore the dark side of space in Out of this World, a new and exciting series for struggling readers. What is dark matter? How does it move our galaxy? These and other fascinating questions are discussed in the Dark Matter title using considerate text that is written at a higher maturity level with a lower reading level to engage struggling readers. A table of contents, glossary with simplified pronunciations, and index all enhance reading comprehension. Sidebars include hands-on experiments, spotlight biographies on women in science, tech connections, and far out facts.