Siglo XXII: El futuro del espacio (22nd Century: Future of Space) 6-Pack

When rocks change because of environmental conditions, the new rocks are called metamorphic rocks. A rock's chemical or physical makeup may change because of conditions such as temperature, stress, or pressure. Your readers will learn fascinating facts including where metamorphic rocks are most commonly found, the different types of metamorphism, and how metamorphic rocks are identified. Full-color photographs depict these rocks in nature. A helpful graphic organizer shows how these fascinating rocks form.

Learn more about the renowned British scientist, professor, and author who spent his entire career trying to answer the question: "Where did the universe come from?" Stephen Hawking was born exactly three hundred years after the death of the scientist Galileo, so maybe it was written in the stars that he would become a famous scientist in his own right. Although he was diagnosed with a neurological disease at age 21, Stephen did not let the illness define his life. Known for his groundbreaking work in physics, and identified by his wheelchair and computerized voice system, Stephen continued...

Bright stars twinkle in the night sky. Have you looked up into the sky on a clear night and seen these tiny points of light? Did you know that there are many kinds of stars in space? Find out all about them in this Spanish-translated book.

La lluvia es un fenómeno atmosférico que consiste en la precipitación de gotas de agua. La intensidad de las lluvias se mide en milímetros de agua caída, es decir, la altura de agua caída recogida en una superficie plana y medida en milímetros. Un milímetro de agua de lluvia equivale a 1 litro de agua por m2, que es otra forma de medir la cantidad de agua de lluvia. Muy pronto va a llover y los niños están listos para explorar y averiguar todo lo que ocurre cuando las negras y amenazantes nubes se juntan. ¿Te has detenido a pensar de dónde viene la lluvia o adónde va?, ¿cómo se ...