"This detective story is magnificently presented . . . [the] chronology of the quest to answer one of the most challenging questions in astronomy." — ChoiceAstronomers have determined that our universe is 13.7 billion years old. How exactly did they come to this precise conclusion? How Old Is the Universe? tells the incredible story of how astronomers solved one of the most compelling mysteries in science and, along the way, introduces readers to f...

In the twenty-first century, the debate about life on other worlds is quickly changing from the realm of speculation to the domain of hard science. Within a few years, as a consequence of the rapid discovery by astronomers of planets around other stars, astronomers very likely will have discovered clear evidence of life beyond the Earth. Such a discovery of extraterrestrial life will change everything.Knowing the answer as to whether humanity has company in the universe will trigge...

Does life exist on Mars? The question has captivated humans for centuries, but today it has taken on new urgency. NASA plans to send astronauts to Mars orbit by the 2030s. SpaceX wants to go by 2024, while Mars One wants to land a permanent settlement there in 2032. As we gear up for missions like these, we have a responsibility to think deeply about what kinds of life may already inhabit the planet-and whether we have the right to invite ourselves in.David Weintraub tells why, of ...

What is an astronomer? What does he or she do? Meet Keivan, a kid like you and me, who grew up and became an astronomer! As a child, Keivan was always interested in learning about planets orbiting other stars and this interest has taken him to the stars! Learn more about how he became involved in a space mission, as part of his research about exoplanets.The Who Me? series features inspirational biographies of scientists who young readers will be able to identify with as people like themsel...

The search for life on Mars—and the moral issues confronting us as we prepare to send humans thereDoes life exist on Mars? The question has captivated humans for centuries, but today it has taken on new urgency. As space agencies gear up to send the first manned missions to the Red Planet, we have a responsibility to think deeply about what kinds of life may already dwell there—and whether we have the right to invite ourselves in. Telling the complete story of our ...

What is a radiation oncologist? What does he or she do?Meet Karen, a kid like you and me, who grew up wanting to become a professional singer. Then she discovered that singing and the science of the human body are related. She then fell in love with science and medicine and became an oncologist. Learn how Karen uses X-rays to help people with breast cancer, how she works to find ways to reduce some of the side effects that make X-ray treatments for cancer painful for some patients,...

Meet Wonder, a kid like you and me, who moved around a lot and went to lots of different schools. As a teenager, she worked as a waitress, at a library, and helped out with older people. Then, she discovered she wanted to become a doctor. Along the way, she met a patient with an illness called sarcoidosis. This patient's immune system was not working the way it was supposed to. Wonder decided that she would learn how to do medical research so that she could learn about this disease. Someda...

Meet Marcelo, a kid like you and me, who grew up in Brazil wanting to become a philosopher and solve logic puzzles. Philosophy led him to physics, and physics led him to mathematics. Learn how Marcelo thinks about mathematical equations as puzzles to solve and how solving one of those puzzles helped him learn about how the universe works.The Who Me? series features inspirational biographies of scientists whom young readers will be able to identify with as people like themselves. Wr...

What is a cancer biologist? What does he or she do?Meet Ben, a kid like you and me, who grew up and became a cancer biologist. As a child, Ben loved playing basketball and reading books, especially Spiderman comic books. In middle school, he fell in love with science and understanding the human body. Learn about how he uses a special technique, called a liquid biopsy, to detect the mutations that cause cancer and about how liquid biopsies help people with cancer know if they are cu...

Meet Larisa, a kid like you and me, who grew up wanting to become a politician. Then she discovered fossils. Learn how Larisa uses fossil teeth to clarify the ancient ecology of saber-toothed cats and other ice age mammals. And learn how Larisa, with help from doctors, managed her epilepsy.The Who Me? series features inspirational biographies of scientists whom young readers will be able to identify with as people like themselves. Written by the scientists themselves and co-authors...

What is a bioarchaeologist? What does he or she do?Meet Tiffiny, a kid like you and me, who grew up and became a bioarchaeologist! Tiffiny's father emigrated from China to the United States before she was born. She grew up exploring museums and the outdoors with her father, and discovered her passion for understanding different peoples and cultures. Learn about how she uses archaeology and biology to understand how people in the past lived and why they moved from one part of the Ea...

What is a quantum dot chemist? What does he or she do?Meet Sandy, a kid like you and me, who grew up wanting to become a school teacher. Then she discovered she loved doing chemistry. Now, she does chemistry research and teaches chemistry to college students. Learn how Sandy discovered a quantum dot that emits white light and how she is working to use quantum dots to track the movement of medicines in brains. And learn how Sandy suffered from seasonal bipolar disorder and then, wit...