Agujeros negros (Black Holes)

For many years, people believed there were nine planets that orbited the sun. Now we say there are eight. What happened to the ninth planet, Pluto? What are the different planets like? What exactly makes a planet a planet? These are the many intriguing questions answered with this high-interest book, crafted to be accessible for readers of all levels. Young astronomers will be especially fascinated by the stunning photographs and the "Make the Grade" fact boxes.

Más del 90% de la biodiversidad del planeta Tierra son microorganismos. Por otra parte, la idea que tiene la gente de los microbios no puede ser más negativa: son unos seres arteros, sigilosos y nocivos que aprovechan cualquier ocasión para ponernos enfermos, y que, incluso, pueden causarnos la muerte. Pero los microbios, también realizan el reciclado de los elementos químicos, producen el oxígeno que respiramos, nos permiten digerir los alimentos y nos defienden de muchas enfermedades. Los microorganismos aportan a la biosfera muchos más beneficios que inconvenientes. Para empezar a...

"Some things are so huge or so old that it's hard to wrap your mind around them. But what if we took these big, hard-to-imagine objects and events and compared them to things we can see, feel and touch? Instantly, we'd see our world in a whole new way." So begins this endlessly intriguing guide to better understanding all those really big ideas and numbers children come across on a regular basis. Author David J. Smith has found clever devices to scale down everything from time lines (the history of Earth compressed into one year), to quantities (all the wealth in the world divided into one...

The unsinkable luxury liner known as the Titanic may have sunk on its first transatlantic voyage in 1912, but people remain riveted to its storied legend. The collision with the iceberg in the North Atlantic was not the only mistake that was made that day. In this spellbinding volume, readers will learn about the passengers and crew aboard the doomed ship and what really happened that tragic night. Historical photographs will transport them back to the glamorous era, while the narrative paints an absorbing picture of the Titanic's sad fate.

What does the sun do for us other than give us light during the day? It gives us warmth, energy, and so much more! Learn all about the sun in this Spanish-translated book.