Jeffrey Bennett, Ph.D., astrophysicist and author of What Is Relativity? An Introduction to Einstein’s Theories, And Why They Matter (Columbia University Press, 2014).

Bennett is also the author of five children’s books that are currently in orbit onboard the International Space Station, where they are being read by astronauts as a part of Story Time From Space. Learn more at www.jeffreybennett.com and follow Jeff on Twitter @JeffreyOBennett. Jeffrey Bennett photo by Bridgette.