Every planet in our solar system is essentially round. But out in the universe, are there any planets that aren’t spherical? Technically, planets are round, by definition; they need to have enough mass to produce the gravity required to pull themselves into a spherical shape. “Actually, one of the specifications for being a planet is, … Read more
Astronomers are proposing a new definition of a planet, nearly two decades after a previous such change led to Pluto’s demotion. The new definition would add measurable criteria, including considerations of the planet’s mass — and it would still leave Pluto with its dwarf planet status. Currently, the International Astronomical Union (IAU) defines a planet … Read more
About one in every 12 stars may have swallowed a planet, a new study finds. Previous research had discovered that some distant stars possess unusual levels of elements, such as iron, which one would expect to make up rocky worlds such as Earth. This and other evidence suggested that stars may sometimes ingest planets, but much remained uncertain … Read more
