RocketSTEM Issue #13 - September 2016 | Page 15

O S I R I S R E x Bringing home a piece of an Asteroid By Sherry Valare Upon first hearing the name OSIRIS-REx, a picture of an unknown carnivorous dinosaur may come to mind. But OSIRIS-REx (Origins-Spectral InterpretationResource Identification-Security-Regolith Explorer) is actually an acronym that names an upcoming asteroid exploration mission. A spacecraft will travel to an asteroid target in a near Earth orbit, perform scientific experiments, and become the first U.S. mission that gathers a sample from the surface to be returned back to Earth for further study. This mission will try to answer some fundamental questions about our existence. What are the building blocks for our creation? What will the future bring? The size of asteroid Bennu, in comparison to two Earth landmarks. Credit: NASA’s Goddard Space Flight Center Conceptual Image Lab. To understand the OSIRIS-REx mission further, let’s take a look at what an asteroid is. An asteroid is not the same as a comet or a meteoroid – there are differences in composition, origin of their formation, and size. An asteroid will have a diameter of at least one meter or more, and it is made of debris left after the solar system formed – primarily minerals and rock. Many asteroids exist – millions, as a matter of fact. Most of the ones we know about reside in a place in the inner part of the solar system called the asteroid belt (which lies in between the orbits of planets Mars and Jupiter), and some even share an orbit with Jupiter. 13 www.RocketSTEM .org 13