Horizons Exploring the Universe AP® Edition, 15th Student Edition

The text's conversational tone and student-friendly approach transcends mere memorization of facts and figures and instead helps students acquire a deep understanding of the Universe.

Each chapter now begins with a new Guidepost feature, which helps students see the organization of the book by connecting the chapter with the preceding and following chapters. Additionally, a short list of important questions highlights the chapter's learning objectives. These valuable tools ensure students stay focused and engaged throughout each chapter.

New How Do We Know? boxes help students understand the inner workings of science. Students will explore fundamental topics such as the difference between a hypothesis and a theory, the use of statistical evidence, the construction of scientific models and more.

The student-friendly Concept Art features provide a visually compelling approach to learning new topics. The two-page format combines ideas and images, enabling students to visually process information and synthesize their own understanding. In-text introductions to the Concept Art features alert students that there are a certain number of points and new terms to look for throughout the chapter. Colors, images and numerical keys thoughtfully guide students to the main concepts, enhancing their overall learning experience.

The text strategically highlights Common Misconceptions throughout the book, which address popularly held misconceptions and myths regarding astronomy.

Each chapter has undergone review and been enhanced with the latest groundbreaking discoveries and captivating imagery.

The fascinating worlds of extrasolar planets are now highlighted in a brand new Chapter 20. Students will discover the latest insights from the Kepler and TESS space telescopes alongside innovative ground-based research programs.

The lunar and solar eclipse tables in Chapter 3 have been updated to include eclipses through the year 2030. This comprehensive update provides the latest and most accurate information, allowing students to witness real-time celestial wonders like never before.

Discover the new subsection in Chapter 4, 4-1 "The Origin of Modern Astronomy", which unveils new research on prehistoric astronomy, including archaeoastronomy and non-European astronomy. Students will expand their cosmic knowledge with updated Concept Art, like the Mars retrograde loops, now extended through 2027.

New and planned observatory facilities, including the James Webb Space Telescope and the Tianyan Radio Telescope, are now featured in Chapter 5 ("Light and Telescopes"), providing students with exclusive insights into both established and forthcoming space telescopes.

Solar cycle plots in Chapter 7 ("The Sun") have been updated to 2023 to give students a comprehensive view of the Sun's fascinating history, patterns and fluctuations.

Chapter 9 ("Star and Planet Formation"), Chapter 10 ("Stellar Structure and Evolution") and Chapter 11 ("Supernovas, Neutron Stars, and Black Holes") have been reorganized, revised and renamed to create a seamless learning experience, where related subtopics are now grouped together. A new section of Chapter 11, 11-4 "Power Unleashed", consolidates text and figures regarding accretion disks, jets, gamma-ray bursts and magnetars, ensuring students gain a deeper understanding of cosmic forces.

Chapter 12 ("The Milky Way Galaxy") includes new images and accompanying text (Concept Art 12A Figure 3a) regarding the Event Horizon Telescope image of Sgr A*. Additionally, students will delve into new end-of-chapter homework problems, such as figuring out the latest calculations of the Galaxy's mass. Utilizing the most up-to-date distance values, these exercises provide a practical application of knowledge and offer a deeper understanding of the intricacies of space.

Chapter 14 ("Modern Cosmology") now features an in-depth discussion on the claimed detection of cosmological gravity waves and subsequent data reanalysis conducted by multiple research teams. These interactive learning prompts offer valuable insights into the rigorous process professional scientists undertake to prevent bias, avoid wishful thinking and validate their findings.

Chapter 15 ("The Solar System") has been reorganized, revised and renamed, with expanded teachings of planet orbital migration. Additionally, content regarding extrasolar planets has been moved to a new chapter.

Students will embark on an enriched exploration of Earth and the Moon in the revised Chapter 16, which includes expanded teachings on the fundamentals of the geological processes of these two celestial bodies.

Chapter 17 ("Mercury, Venus, and Mars") has been updated with new discoveries and captivating images. For example, a new Concept Art spread depicting modern-day space exploration offers students an immersive and engaging learning experience they won't want to miss.

Chapters 18 ("The Giant Planets") and 19 ("Comets, Asteroids, and Meteorites") have undergone meticulous reorganization, revision and renaming, resulting in a more cohesive learning experience. Highlights include the relocation of content on Pluto and the Kuiper Belt from Chapter 18 to Chapter 19, updated findings and images from spacecraft and ground-based observations in both chapters and the consolidation of Concept Art spreads depicting the rings of the Jovian planets in Chapter 18. Along with these new revisions, a brand new Concept Art spread was added, showcasing the Galilean satellites of Jupiter and active satellites of Saturn.

Chapter 21 ("Astrobiology: The Search for Life on Other Worlds"), previously known as Chapter 20 in HORIZONS 14th Edition, is now updated with fresh content and cutting-edge imagery.