In 2015, two astronomers from Caltech presented evidence that six objects past the orbit of Neptune were bunched together in a way that suggested they were being "herded" by something with a large ...

The number of planets that orbit the sun depends on what you mean by “planet,” and that’s not so easy to define ...

Kuiper Belt, well past the orbit of Neptune (artistic illustration). There may be an undiscovered planet in the outer solar system whose presence is revealed by the strange orbit of objects beyond ...

Pluto resembles the icy, comet-like objects orbiting the Sun outside of Neptune's orbit, rather than either the rocky terrestrial planets or the Jovian planets. Factors that distinguish Pluto from ...

It probably spent nearly all of the past 4.5 billion years in a deep freeze beyond Neptune, inside the comet Wild 2 (pronounced VILT-two). Decades ago Wild 2 somehow got nudged into an orbit that ...

An object eight times the mass of Jupiter may have swooped around the sun, coming superclose to Mars' present-day orbit ...

In general, as the distance from the Sun increases: the temperature decreases, for example, Mercury is 430 °C whereas Neptune is -200 °C the time taken to orbit the Sun increases, for example ...

In general, as the distance from the Sun increases: the temperature decreases, eg Mercury is 430°C whereas Neptune is –200°C the time taken to orbit the Sun increases, eg Mercury orbits once ...