What Caused this Strange Asteroid
Scientists Study Unique Images Brought Back From Space
by Patricia Cazares, age 12
An asteroid is a rocky, metallic object in the sky that orbits the sun. An asteroid belt is filled with many kinds of asteroids whose shapes have been formed by years of collisions.
Scientists are currently studying images of an asteroid called (2867) Steins, which has a unique diamond shape. These scientists believe that the bizarre shape is caused by a phenomenon known as Yarkovsky-O’Keefe-Radzievskii-Paddack, or YORP.
This phenomenon occurs when the sun hits an object in space, and the object emits photons, which changes the rotation. These photons produce varying amounts of torque, a twisting force that causes the rate of rotation to either slow down or speed up.
German scientist Horst Uwe Keller and his colleagues reviewed images of this asteroid collected during the European Space Agency’s 2008 mission, Rosetta. The team says the asteroid might be a collection of bits and pieces rather than solid rock. Scientists studying the images suggest that the YORP effect increased the asteroid’s spin and shifted a portion of its mass to its equator, giving the asteroid its diamond shape.
[Source: The New York Times; Webster’s II New Riverside Dictionary]