Chasing Comets, Asteroids and Mysterious Space Objects
Chasing Comets, Asteroids and Mysterious Space Objects
Like Eros, Itokawa has an orbit that brings it near Earth. It was discovered in 1998 by researchers studying near-Earth asteroids (NEAs) and named for Hideo Itokawa, a famous Japanese rocket engineer. Itokawa is a very small S-type asteroid, less than half a mile (1 km) long. Because it is so small, its gravity is too weak to hold a spacecraft in orbit around it. Hayabusa had to adjust its own orbit around the Sun to match that of the asteroid until it had “parked” itself in a position about 12 miles (20 km) above the surface.
Six titles comprise Crabtree’s new “Mission: Space Science” series which examines the solar system as well as some of the history and the future of space exploration. Detailed information, accompanied by photographs, artists’ renderings and diagrams, furthers readers’ understanding of the universe. Sidebars provide additional information, and “Your Mission” text boxes pose questions and scenarios for readers to ponder. At the back of the book is a “Planning Your Mission” activity for readers to try. This activity involves goal-setting, critical thinking, creativity and problem-solving. In most cases, the student has to decide on a research topic or type of mission, design an appropriate spacecraft, select the proper tools to take along, the methods of recording data, and finally, collaborate with others to brainstorm for ways in which to improve the mission. Though the vocabulary used in the text is not difficult, many of the concepts presented in the series are quite complex, and so the books might appeal only to space buffs. Occasionally, the information is repeated throughout the various titles, and some of it is available in other series by the same publisher. A table of contents, a glossary, an index and a list of books and web sites are also provided.
Chasing Comets, Asteroids, and Mysterious Space Objects explains the differences between comets, asteroids and dwarf planets- their size, composition and movement. One of the main reasons that scientists want to study asteroids is that asteroids contain minerals which might be able to be mined, though it would be an extremely expensive endeavour. Another reason is that the minerals, resources and water found in asteroids might supply future space colonies on Mars or the Moon. (One speculation is that Earth’s water might have come from an asteroid.) Other topics in this title include the discovery of Halley’s Comet, avoiding impact with comets and asteroids, the problems that spacecraft encounter when studying these foreign bodies, and how scientists use information garnered from the study of asteroids and comets to find clues about how the Earth was formed.
Generally, “Mission: Space Science” is a good series, but some of the titles will have a limited audience.
Gail Hamilton is a former teacher-librarian in Winnipeg, Manitoba.