Scientists use data from the New Horizons mission to illuminate the mystery.
Charles Q. Choi, Contributor
Observations of the region beyond the planet Neptune are giving astronomers fresh understanding of our solar system's history – and may reveal a new planet.
Peter Gwynne, Contributor
New observations point to processes driving away the atmosphere, rendering the planet's surface inhospitable to life.
Ramin Skibba, Contributor
New research explains the careful choreography of a multi-planet system called Kepler-233.
Abigail Malate, Staff Illustrator
Eclipses would be a thing of the past.
Marsha Lewis, Contributing Producer
In 130 million years, these planets will become dinner for their dying host star.
Cynthia McKelvey, Contributor
Researcher finds convincing evidence for water molecules inside Venus.
Jessica Orwig, Contributor
Inside Science is an editorially independent news service of the American Institute of Physics