An artist's impression of Sedna, with a hypothetical moon near it and the Sun, like a bright star, in the background (Image: NASA/JPL-Caltech). These comets are much faster at completing this orbit ...

A physics phenomenon discovered 150 years ago allows tiny objects to levitate using just sunlight – and now it could enable swarms of sensors to explore part of Earth’s long-neglected upper atmosphere ...

New research has uncovered compelling evidence that water from a comet is strikingly similar to that found in Earth's oceans, ...