In 2006, Pluto was famously demoted from a planet to a dwarf planet. It remains the most famous dwarf planet today, but there are others in our solar system, including potentially hundreds that ...

Two decades ago, Pluto was reclassified as a dwarf planet, sparking an enduring debate. NASA Administrator Jared Isaacman says he wants to “make Pluto a planet again.” ...

The reclassification of Pluto as a dwarf planet continues to stir up a hornet's nest of controversy and debate, as Space.com meets one astronomer who believes the decision to have been a mistake.

New observations reveal that the far-flung object 2014 UZ224 (informally known as DeeDee, for "Distant Dwarf") is about 395 miles (635 kilometers) wide — big enough to claim "dwarf planet" status.

A team of scientists at the Institute for Advanced Study School of Natural Sciences in Princeton, New Jersey, might have found a new dwarf planet, potentially leading to more evidence of a theoretical ...

An international team of astronomers have discovered a new dwarf planet orbiting in the disk of small icy worlds beyond Neptune. The new object is roughly 700 kilometers in size and has one of the ...

A color-enhanced view of Ceres, the nearest dwarf planet to Earth, high­lights its Oc­ca­tor crater. Credit: NASA / JPL-Caltech / UCLA / MPS / DLR / IDA Pluto is the most famous dwarf planet, due in ...

Do aliens sleep? You may take sleep for granted, but research suggests many planets that could evolve life don’t have a day and night cycle. It’s hard to imagine, but there are organisms living in ...

Astronomers found a massive object orbiting a brown dwarf star. This discovery challenges existing definitions of planets and moons. The unusual system features a nested orbital arrangement unlike our ...

Hubble Space Telescope observations of white dwarf star G238-44 has shown that it is "consuming both rocky-metallic and icy material, the ingredients of planets," according to NASA's Goddard Space ...

A rare type of plutonium has been found in the crust below the deep sea, offering new clues as to how heavy metals form in star explosions and mergers. Strange hexagonal diamonds may have been ...