Pluto hasn't been a planet for almost 20 years. In the early 2000s, scientists discovered several objects of a similar size to Pluto. So, during the summer of 2006, members of the International ...

In 2015, scientists got their best glimpse yet of dwarf planets, when two NASA spacecraft visited distant worlds. In March, the Dawn mission arrived at Ceres, which lies in the asteroid belt between ...

A kindergartener in 2005 and a kindergartener in 2006 would have learned very different facts about the number of planets in the solar system. 2006, of course, was the year Pluto was reclassified as a ...

The word “planet” came from the ancient Greek words that mean “wandering star.” That makes sense, because for thousands of years, people have watched planets change position in the night sky – unlike ...

The International Astronomical Union (IAU) defined a dwarf planet in 2006 as a celestial body that orbits the Sun, is round in shape, but has not cleared its orbital neighborhood of objects of ...

Nearly a decade ago, Pluto was stripped of its planetary status. But if you were alive two centuries ago, you could have been just as smug about Ceres, too. On March 6, NASA’s Dawn spacecraft will ...

This weekend, you can watch live as the first asteroid ever discovered passes across one of the night sky's most beautiful spiral galaxies. This weekend, Ceres will appear to "meet" the distant spiral ...

Am I seeing spots before my eyes? New images from the Dawn spacecraft show lots more detail on the asteroid Ceres. We're getting closer and closer to Pluto. Asteroid / dwarf planet Ceres mystery white ...

If you woke up Thursday morning and sensed something was different about the world around you, you’re absolutely right. Pluto is no longer a planet. The International Astronomical Union, wrapping up ...

Pluto may be a more habitable world than scientists had thought. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. Though Pluto is now famously ...

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Animation made from still images of Ceres taken by Dawn on Feb. 4, 2015. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/PSI New images from NASA's Dawn spacecraft reveal ...