Live Science on MSN

'Planet Y' theory hints at hidden Earth-size world lurking in the solar system — and it could be much closer to us than 'Planet Nine'

A new study has proposed the existence of Planet Y, an alternative Planet Nine candidate that is smaller and closer to Earth ...
Chip Chick on MSN

New Evidence Of Another Planet Was Uncovered, And It Could Be Around The Same Size As Earth

For almost a decade, astronomers have been searching for a ninth planet in the solar system. Recently, new evidence of ...
The News-Times

Even planets have their (size) limits

Scientists have discovered over 4,000 exoplanets outside of our Solar System, according to NASA’s Exoplanet Archive. Some of these planets orbit multiple stars at the same time. Certain planets are so ...
SpaceRef

Earth-Size Planets Are Common in Our Galaxy

An analysis of the first three years of data from NASA’s Kepler mission, which already has discovered thousands of potential exoplanets, contains good news for those searching for habitable worlds ...
nerdist

Video Imagines How Big Countries Would Be as Planets

There’s something about comparing the sizes of unthinkably large objects that’s endlessly intriguing. Looking at a comparison of all the various sizes of stars in the universe, for example, makes for ...
Newsweek

Scorching Hot Planet the Size of Jupiter Is as Dense as a Marshmallow

Astronomers have discovered a new Jupiter-sized exoplanet that possesses less than one-third of the mass of the solar system's largest planet, giving it a density similar to a marshmallow. The team ...