Do Newfound Alien Planets Need Better Names?

Kepler20e cut
An artist's rendering of the newfound alien planet Kepler-20e, which scientists say is smaller than Earth, at about 0.87 times the width of our planet.
(Image credit: NASA/JPL-Caltech/T. Pyle)

Astronomers on Tuesday (Dec. 20) announced the discovery of the first two Earth-size alien planets — a historic find for sure, but the newfound worlds didn't exactly receive historic names.

The two alien planets are officially known as Kepler-20e and Kepler-20f, a nod to the instrument that detected them, NASA's prolific Kepler space telescope. The planets' host star is Kepler-20, and the letters indicate that 20e was the fourth planet discovered in this alien solar system and 20f the fifth. (By convention, the first planet found in a system is always designated "b," not "a.")

Mike Wall
Space.com Senior Writer
Michael was a science writer for the Idaho National Laboratory and has been an intern at Wired.com, The Salinas Californian newspaper, and the SLAC National Accelerator Laboratory. He has also worked as a herpetologist and wildlife biologist. He has a Ph.D. in evolutionary biology from the University of Sydney, Australia, a bachelor's degree from the University of Arizona, and a graduate certificate in science writing from the University of California, Santa Cruz.